I didn't make a simple list of the brand names that I trusted before. Here it is.
Valve's and T's (& tubing) $30 John Guest
Filter 1 $10 MatrikX
Filter 2 $10 MatrikX
Filter 3 $15 MatrikX
Filter 4 $15 Omnipure
Membrane $40 Filmtec
Flow restrictor $15
Permeate Pump $45 Aquatec
"90%" cut-off valve $15 Hydronamic
4 Gallon Tank $70 ROPRO
Faucet $30 Touch-Flo
TDS meter $15 Hana
Flow meter $30 DigiFlow
Filter housing $60
check valve $7 (instead of air-gap faucet)
Total $407
The price were a while ago. Google manufacturer's name or on eBay, so you get good price. From time to time, people just buy in bulk and sell them separately on eBay close to wholesale price but still make a profit. It's difficult to bait and switch and I think it's impossible to have fake items.
To see what you get for $390 see this Flomatic system I just came across. It's completely NSF certified (like mine) and it looks very much like my system (and any other system) except for the integration (to save labor cost for them probably). However, there is no pump, so the performance is inferior and probably the filters and membrane are not the best.
John Guest is the patented name of the tubing connection system and also the manufacturer of a few things. JG is the easiest system - leak proof. Valve is important because I told you before Lowes sell valves near ice maker tubings that carries a health warning. JG is NSF certified. All it's valves come with a beautifully fine JG symbol on it. You need a very fine plastic moulding process to copy that. If you have the tech and money to imitate it or fake it, you should have done a lot of other things than making some valves. JG make tubings too, though you can also find NSF certified tubings in hardware stores.
MatrikX filters are well known and well established, certified. Also a solid piece of work holding in your hands. The paper labels are well printed and now there are trademarks moulded on the filter housing, if I remembered correctly. Again if you can make that solid piece of fine work, so heavy, for $10, you can make a lot of other things to make money. Prefilters are for chlorine absorption to protect the membrane, though you can add some fancy filtering capabilities. Since my TDS readings are the same when the filters are new and a few years later, they are working as they should.
Omnipure is similar. MatrikX is the master of block carbon for prefilters, while Ominpure is the master of granular carbon for post filter - not for chlorine absorption. I think it's there to eliminate the taste due to bladder in the tank, at least my 1st cheap tank. Fine labels are printed directly on the housing.
Flow restricter doesn't matter because it's on the brine (waste water) path. But you do need to have the correct flow rate to match your membrane.
There is only one manufacturer for the permeate pump, Aquatec, who also makes a lot of other electric pumps for years. It's a certified component. The pump is completely sealed in tough plastic. The protective plastic doesn't look beautiful but it works - I measured the pressure and TDS. Not anybody can make something like that work - on and on 24/7/52. The smaller one is quiet but limited to 50 gpd and below (check).
The "90%" automatic cutoff valve from Hydronamic is a bit of mystery. They make a lot of other conventional RO valves with typically 60% cutoff. I bet they have some certified 60% valves but I didn't remember if I checked. It's has been a while now but the 90% valve is still not on their website while others are there. But there are no other valves like that on the market. There are controversy about the run away of the term 90%. They aren't - I talked to the manufacturer. But it's not really their fault because they don't sell retail. They do promise to check my valve and replace it if it doesn't goes up to 85%. But I changed my mind about it. Firstly, the value shouldn't relate to water quality - the pump make sure of that by isolating the two parts. The tank should fill more due to higher pressure but 4Gal is more than enough for me - there's no smaller one. I have at least 70 psi input feed, 90% gives 63 psi, higher than most people's main water pressure! My valve is probably 70%, a lot lower than 85% but at 50 psi it's supposed to be the standard main pressure! Conventional 50% valve doesn't have anything wrong in them. But now I know some fridge need 30 psi for ice maker. So you need at least 50 psi at the input.
ROPRO tank makes the others look like toys. It's certified, indestructible, beautiful and space saving. If you stand it upright, make sure your cabinet can stand the pressure, 4 gal per 9" diameter. You can stand it sideways or anyway you want. My 1st metal tank dented, chipped, and leak air. I need to pump it like a tire once a while near the end, and water smell of rubber. Never need to do anything about the ROPRO. The name is mounded on the housing. Actually I wanted to buy a certified metal tank to save money but the retailer give me this for the same price. I bet he didn't sell inferior metal tanks anymore and ran out of stock.
Everybody use Touch-flo faucet because any designer faucet cost $100 to hundreds. Touch-flo's are certified. Now they comes with tubings attached so you save a lot of terrible work at the deepest corners under the sink. The ones I got do not have markings on the faucet because most OEM's use them. They are sold in complete systems by other manufacturers - with or without their brand names etched on the faucet. Forget about air-gap - they can be very noisy and you need extra tubing and connections. It's the same as the air-gap on your dish washer. Just add a check valve so when your kitchen sink blocks, the waste water won't go back to foul your drinking water. I don't think it's a real problem, as long as you remember to disconnect the brine tube from the kitchen sink drain, like a manual on-off valve, before you pour poisonous drain cleaning chemicals down the drain.
Get a TDS meter, so you installation is fail safe. You can't get 95% TDS rejection any other way.
Flowmeter is rather new, in a form suitable for RO systems, monitoring a few different filters and tell you when to change it if you input sufficient data. I haven't tried it. It's rather bulky, a box stick to the front of you system with 3/4" connector. But I think replacing one of the 3 prefilter housing with this will make more sense. It's not certified I think but it claims they use certified material. That's very true, as long as they use certified plastic in contact with drinking water, it should be OK. That goes for the filter housing too. I don't think you can get branded name housing with NSF certification at a good price. But really it's a piece of plastic - if they use appropriate material, and the mold is fine and doesn't leak, how wrong can it be?
Monday, July 7, 2008
Wednesday, January 23, 2008
The law of juggling and the U-defense in desktop tower defense
As you have seen from previous videos, juggling is required to get high score, and to survive the 100 levels. This is a study to find successful juggling strategies and to simplify juggling, so easy that nobody hates it anymore.
For various reasons, the line of creeps in your maze will grow longer and longer, making it impossible to block your creeps in the maze by selling and building towers in different places.
To be successful you have to minimize the line of creeps, and to be able to shorten the line.
Minimizing the length of the line of creeps is easy to say:
- The creeps on the two entrance should enter you maze at the same time. For the worse timing, you have lines of creeps twice as long.
- Creeps should come out at the same time rather than gradually, using the "send next creeps button".
To be able to shorten the line of creeps in the maze keep you in an invincible position. For this I came up with the U-defense. But sadly, after I reinvented it, I spot something similar in the videos that was not obvious because of the fast play speed.
The maze shown is a straight forward implementation of a double U-defense. The middle 4x6 towers are about enough to deploy air defense in a mix of swarm, boost and snap towers. The lower right corner shows the two exits of the maze. One of the exist are always blocked. Since you can actually shorten the line of creeps, other strategy isn't that important, unless you reach the point of aiming at the highest score.
The critical tower are the two towers marked "g", which can be seen as a return valve by passing a large U shaped path. When the creeps enter the U, they are slowed down. When they passed the U and then returns because of blocking, if the U valve is open, the later creeps to return will catch up with the earlier creeps, shortening the line of creeps!
The timing principle is simple. When the first creep enters and exits the U, passing the g-tower the 2nd time, this g valve can be open at the exact time but no earlier. If the valve is opened earlier, other creeps will find a short cut and pass the first creep to lengthen the line of creeps. Now when the exit is blocked and the first creep returns, it will return via the g-valve, catching up with other creeps returning not from the g-valve. So the line of creeps is shortened.
The juggling sequence is very simple. One of the exits is blocked. When the first creep passes through the middle of the U, it's time to sell the valve and the blocking tower in the other exit at the same time. It's so simple you can't forget it, and there's no extra difficulty other than simple juggling. When the selling is complete, you block the current exit, so some creeps return via the normal path and some return via the valve. After the last creep returns via the valve, block it. Then rest a little and do the same for the other path. Note that this timing is for the maximum sell time. When selling is fast at the beginning of the game, you can sell the valve-tower and the block-tower later.
Sunday, January 13, 2008
Personal computer regular maintenance
Do PCs, like cars, need oil and filter change? Sure, unless you, like many people, replace whole desktops or laptops every two years. But even if you do, you will have measurable benefits by doing regular maintenance.
The efficiency of air cooling systems using fans and heat sinks degrade with time. Most PCs have mechanisms to slow down the processor when over heating occurs. Typically mobile processors in laptops slow down significantly after long use, especially with the fan grills blocked. Slow down support is built into mobile processors. Desktop processors didn't, not until the latest ones. You also need system board level and operating system level support. So, if you keep the fans and heat sinks at top form, your PC runs fast and runs safe.
One more thing you may need to do is to reapply thermal paste between the CPU and the head sink. The chewing gum like paste that comes with new CPU's last for years. But once you disconnect the CPU from the heat sink, the paste will be very bad to reuse. So if you build your own system, you get only one chance if you want a good thermal contact. They are not supposed to be good anyway. Circuit City has a lot of more fluid like thermal compounds on sale, which claim to be better. But I just discovered that they don't last that long. But replying them is trivial.
Other maintenance include cleaning the monitor and keyboard. They are hardly life threatening, unless you have a wife like mine. I have quality screen cleaning fluid and micro fiber cloth for my expensive monitor. Normally it's quite dusty as I believe cleaning cause degradation. I only clean it when I need to calibrate color for example, or to view some very high quality image, or just it's too dirty to look at. But once I left my monitor alone for a while, my wife cleaned it like windows, not the software kind but the glass kind. I was horrified by the marks left on my dear monitor. I could image how she cleaned windows, spray on some Windex, and rub it hard with a towel, OMG. Luckily, after I wipe the screen repeatedly with my cleaning fluid, there didn't seem to be any harm done.
When do you need to do maintenance work? I had no choice because my system board alarm went off due to over heating. Lesson number one, you must turn on the temperature monitor alarms. In the past, I use the system board software utilities when the board is new, to verify that everything is working and no overheating. After that, I tend to ignore those utilities because they are quite primitive software from hardware manufacturers, a pain to use. But I learned to keep them on when the system boots, it will be useful years later.
My CPU reaches 60 deg C whenever the anti virus software is scanning my disks. The CPU usage is only some 50%. So I know there must be something wrong. Lesson number two, on a brand new PC, record the fan speed and temperatures when your PC is doing something heavy continuously, such as anti virus scanning, and playing videos. So when your fan speed or temperatures are significantly higher at the same conditions, you know it's time. Or, you can just wait for the alarms to go off.
I clean the heat sinks on the system board using a can of compressed gas duster for computers, which you can find in hardware stores nowadays. I also use it for all the fans in the power supply and in the case. Otherwise, it's hard to wipe the fans clean. I also use the duster to blow away dust from the system board components, and the keyboard. These are hardly necessary but feel good.
Don't mix thermal paste, old and new. The thermal paste that comes with retail processors are hard to remove completely. But those semi-fluid thermal paste are easy. You just need rubbing alcohol and they disappear completely. Then you reapply a drop or two of paste. These paste are usually contained in a tiny syringe, sufficient to be applied for a 100 years. But you are supposed to store them upright. I did keep the syringe upright after I was done installing my new system.
By the way, hot laptops cause low sperm counts, or something like that.
The efficiency of air cooling systems using fans and heat sinks degrade with time. Most PCs have mechanisms to slow down the processor when over heating occurs. Typically mobile processors in laptops slow down significantly after long use, especially with the fan grills blocked. Slow down support is built into mobile processors. Desktop processors didn't, not until the latest ones. You also need system board level and operating system level support. So, if you keep the fans and heat sinks at top form, your PC runs fast and runs safe.
One more thing you may need to do is to reapply thermal paste between the CPU and the head sink. The chewing gum like paste that comes with new CPU's last for years. But once you disconnect the CPU from the heat sink, the paste will be very bad to reuse. So if you build your own system, you get only one chance if you want a good thermal contact. They are not supposed to be good anyway. Circuit City has a lot of more fluid like thermal compounds on sale, which claim to be better. But I just discovered that they don't last that long. But replying them is trivial.
Other maintenance include cleaning the monitor and keyboard. They are hardly life threatening, unless you have a wife like mine. I have quality screen cleaning fluid and micro fiber cloth for my expensive monitor. Normally it's quite dusty as I believe cleaning cause degradation. I only clean it when I need to calibrate color for example, or to view some very high quality image, or just it's too dirty to look at. But once I left my monitor alone for a while, my wife cleaned it like windows, not the software kind but the glass kind. I was horrified by the marks left on my dear monitor. I could image how she cleaned windows, spray on some Windex, and rub it hard with a towel, OMG. Luckily, after I wipe the screen repeatedly with my cleaning fluid, there didn't seem to be any harm done.
When do you need to do maintenance work? I had no choice because my system board alarm went off due to over heating. Lesson number one, you must turn on the temperature monitor alarms. In the past, I use the system board software utilities when the board is new, to verify that everything is working and no overheating. After that, I tend to ignore those utilities because they are quite primitive software from hardware manufacturers, a pain to use. But I learned to keep them on when the system boots, it will be useful years later.
My CPU reaches 60 deg C whenever the anti virus software is scanning my disks. The CPU usage is only some 50%. So I know there must be something wrong. Lesson number two, on a brand new PC, record the fan speed and temperatures when your PC is doing something heavy continuously, such as anti virus scanning, and playing videos. So when your fan speed or temperatures are significantly higher at the same conditions, you know it's time. Or, you can just wait for the alarms to go off.
I clean the heat sinks on the system board using a can of compressed gas duster for computers, which you can find in hardware stores nowadays. I also use it for all the fans in the power supply and in the case. Otherwise, it's hard to wipe the fans clean. I also use the duster to blow away dust from the system board components, and the keyboard. These are hardly necessary but feel good.
Don't mix thermal paste, old and new. The thermal paste that comes with retail processors are hard to remove completely. But those semi-fluid thermal paste are easy. You just need rubbing alcohol and they disappear completely. Then you reapply a drop or two of paste. These paste are usually contained in a tiny syringe, sufficient to be applied for a 100 years. But you are supposed to store them upright. I did keep the syringe upright after I was done installing my new system.
By the way, hot laptops cause low sperm counts, or something like that.
Tuesday, January 8, 2008
Second additional mobile line (VoIP)
The most straight forward is the Mobile Line 2 service. As the name says, you get another phone line (and number) on your existing mobile phone without affecting your carrier plans. All of these "virtual" phone services route calls via the Internet (VoIP) to be cost efficient. To use the service you need to download an application to your smart phone, which include many Java enabled phones. The cost is $9.99 per month plus less than $0.03 per minute. The cost is higher but comparable to a 2nd prepaid SIM card at low usage. There's no mention of International calls out of USA.
The better service seems to be TalkPlus. You can use smart phones including the iPhone, or dumb phones with just a browser. The cost is $9.99 per month with plenty of minutes included. International calls cost extra but cheap. You can get an international number too.
You can get a virtual phone number for free or very cheap. Incoming calls are easy. The problem is outgoing calls. There's no problem if your recipients take anonymous calls with blocked caller IDs, or you can call your recipients using any phones and ask them to call you back on your virtual number. For example, Skype out do not have outgoing caller IDs.
Google's GrandCentral is the exception. It's free for the moment but you have outgoing caller ID. The philosophy is to have a universal phone number to replace all your other numbers. But of course you can use this number as a 2nd mobile phone line. The added advantage is that you can use any phones when you have internet access. For mobile phones you just need a browser.
These mobile services all use your carrier's airtime for the duration of the call, and need a data plan for accessing the internet to setup the calls. For prepaid phones, the most expensive can be $0.25 per minute and a few cents per kilobytes. AT &T Cingular prepaid includes data plan, while Virgin phones typically weren't even internet capable. Typically a GrandCentral call uses less than $0.10 (prepaid) for data plus airtime.
Perhaps to limit free usage, you can only call somebody if you add it to the contact list first. This is a small deal but the funny thing is that you cannot add contacts at the mobile version of the site. Otherwise to call your contacts or return incoming calls via your mobile is simple, using one-click on the entry. My mobile phone works fine but one day I couldn't call anymore. I exchanged emails with Google support for a while but they couldn't solve the problem. My phone isn't too new or too smart or too old. It was on the compatible list of TalkPlus.
There is a little known service, or little thought of service that compliments any of the above services. You can call from any phone as if you are calling from your virtual number. You can setup calls using the internet, or via a toll free number. It's TalkPlus when you don't have or don't want to use your mobile phone. You can choose any phone number that you want your recipient to return your calls. It's GrandCentral when you can dial any number directly even with your cell phone.
It's the caller ID spoofing service such as Spooftel. It had been available for a couple of years now. You can just select your caller ID to your virtual number or any number you want. They don't have a mobile website so you may have to use the toll free access if you don't have a computer and internet. But you can always call somebody with a computer to connect the call for you. The cost is $0.10 per minute. Together with free GrandCentral, the combination is cheaper than the cheapest prepaid card. It's really pay as you go because the minutes do not expire.
The catch is, the bill to outlaw caller ID spoofing is at it's final stages, with the latest action last December. The bill is sort of agreed by all parties for a year now. Maybe there are as little as a few more months to go, or maybe a year. Maybe the cutoff date will be set further ahead to give some time for people to get ready.
ps I agree that carriers are trying to block the new VoIP services. When the mobile GrandCentral launched, it worked flawlessly. Then a couple of months ago I could access the mobile site but couldn't call. Now I can't even access the mobile site.
GC support didn't know what's the problem, and I haven't see any conspiracy theory yet. But I see good reason to block these services. When GC forward calls to your mobile, you can have the caller ID set to your GC number. If you add this number to your fav numbers, you have unlimited incoming calls for everybody calling your GC number.
The better service seems to be TalkPlus. You can use smart phones including the iPhone, or dumb phones with just a browser. The cost is $9.99 per month with plenty of minutes included. International calls cost extra but cheap. You can get an international number too.
You can get a virtual phone number for free or very cheap. Incoming calls are easy. The problem is outgoing calls. There's no problem if your recipients take anonymous calls with blocked caller IDs, or you can call your recipients using any phones and ask them to call you back on your virtual number. For example, Skype out do not have outgoing caller IDs.
Google's GrandCentral is the exception. It's free for the moment but you have outgoing caller ID. The philosophy is to have a universal phone number to replace all your other numbers. But of course you can use this number as a 2nd mobile phone line. The added advantage is that you can use any phones when you have internet access. For mobile phones you just need a browser.
These mobile services all use your carrier's airtime for the duration of the call, and need a data plan for accessing the internet to setup the calls. For prepaid phones, the most expensive can be $0.25 per minute and a few cents per kilobytes. AT &T Cingular prepaid includes data plan, while Virgin phones typically weren't even internet capable. Typically a GrandCentral call uses less than $0.10 (prepaid) for data plus airtime.
Perhaps to limit free usage, you can only call somebody if you add it to the contact list first. This is a small deal but the funny thing is that you cannot add contacts at the mobile version of the site. Otherwise to call your contacts or return incoming calls via your mobile is simple, using one-click on the entry. My mobile phone works fine but one day I couldn't call anymore. I exchanged emails with Google support for a while but they couldn't solve the problem. My phone isn't too new or too smart or too old. It was on the compatible list of TalkPlus.
There is a little known service, or little thought of service that compliments any of the above services. You can call from any phone as if you are calling from your virtual number. You can setup calls using the internet, or via a toll free number. It's TalkPlus when you don't have or don't want to use your mobile phone. You can choose any phone number that you want your recipient to return your calls. It's GrandCentral when you can dial any number directly even with your cell phone.
It's the caller ID spoofing service such as Spooftel. It had been available for a couple of years now. You can just select your caller ID to your virtual number or any number you want. They don't have a mobile website so you may have to use the toll free access if you don't have a computer and internet. But you can always call somebody with a computer to connect the call for you. The cost is $0.10 per minute. Together with free GrandCentral, the combination is cheaper than the cheapest prepaid card. It's really pay as you go because the minutes do not expire.
The catch is, the bill to outlaw caller ID spoofing is at it's final stages, with the latest action last December. The bill is sort of agreed by all parties for a year now. Maybe there are as little as a few more months to go, or maybe a year. Maybe the cutoff date will be set further ahead to give some time for people to get ready.
ps I agree that carriers are trying to block the new VoIP services. When the mobile GrandCentral launched, it worked flawlessly. Then a couple of months ago I could access the mobile site but couldn't call. Now I can't even access the mobile site.
GC support didn't know what's the problem, and I haven't see any conspiracy theory yet. But I see good reason to block these services. When GC forward calls to your mobile, you can have the caller ID set to your GC number. If you add this number to your fav numbers, you have unlimited incoming calls for everybody calling your GC number.
Single cell phone multiple numbers (SIM method)
Two lines (two numbers) on one mobile phone is a popular demand. All non-ancient GSM phones support multiple lines, but it seems that no carrier in the world bother to support it. This is true a couple of years ago to last two years, not very true now, but the biggest and most popular carriers don't bother. Now still no US carrier bothers. Now the phones are so smart that you can do a lot of things to by pass the carriers, forcing some carriers to compete. The smaller carriers might just as well provide some fringe benefits to increase head count.
For GSM and 3G(UMTS) you can play around with the SIM cards. For other carriers, you can call via some calling card like services, or Internet services.
You can buy a super SIM card, together with a card reader and writer. You copy all your carrier SIM cards over to your own super SIM card. I heard that 3G SIM's are not possible to copy due to encryption. The original SIMs have to be compatible to your super SIM and to your phone, which makes this the most problematic method, though the most elegant.
The most common method is to get a dual-SIM adapter. I think Magicsim is the most common brand on eBay and I had one, long before they have a brand name and a website online. SIM's have some sort of standards, including V1, V2 and 3G. There are also different memory sizes, 32K, 64K to 128K (3G). Make sure that your phone is on the adapter compatible list. I don' t know if it's possible that some carrier SIM's can cause further compatibility problems. But I don't think it will be if your phone is a 3G or late GSM model.
There are two types of dual-SIM adapters. The simpler type looks like three SIM cards connected together. There are two holders for your carrier SIM cards. You insert the third card into the SIM compartment of your phone. This type requires that your battery compartment isn't too tight to contain the extra thickness of the SIM cards. You are OK if your phone is on the compatibility list. I would recommend this though I had the other type.
The second dual-SIM adapter requires you to cut out the central bit of your SIM cards, and put them into a SIM card that holds your two little cut out pieces. The adapter in the form of a SIM card is slightly thicker than an ordinary SIM card, so it might not fit if your SIM compartment is super thin. Or the contact may be loose so they provide you with sponge fillers for a tight fit.
The cut out type adapters sound dangerous and difficult. It's yes or no. SIM cards don't cost much if you know where to find, and if you have a plan your carrier may replace it for you. Unless you make very stupid cuts, even if the adapter doesn't work, they provide two holders for you to hold your cards for use as if they are not cut. I advise to get a SIM cutter, which I didn't. I just used a scissor. I intended to cut a little larger than the template, then gradually reduce the size to fit the adapter. But I ended up simply chopped off the excess with one simple cut per straight edge.
The two cut out SIM cards should look exactly like two miniature SIM cards, but not mine. After a little trimming they can go inside the adapter. But with some loose space one of the miniature card can move a little inside. It didn't work at first, or it didn't work reliably. But once I swapped the two miniature cards, they fit better and never gave me problems. Maybe after a year the SIM's are lose again. So I pull out and plug in the cards again and added the sponge filler to hold the cards tighter. It works fine now.
I brought a 64K SIM served by AT&T (previously Cingular). It was another eBay order without phone and plan. It was for the GoPhone, prepaid or with a monthly plan. It might be possible that the carrier may not activate some cards, they way they are sold or according to their serial numbers. My SIMs are OK but probably because I wanted to port my old phone number to the prepaid phone(!), I went through several operators. Virgin had better service and better deal, but they are not GSM, reselling Sprint airtime.
I had a carrier unlocked GSM phone for traveling. I don't think you need an unlock phone when you are using two SIMs from the same carrier. If you ask, a nice carrier may unlock the phone for you after 6 months. But most phones are trivial to unlock yourself. For Moto you only need to download some software to the PC and a standard mini USB cable. I don't know about the latest 3G phones but you always search unlock hacks specific for your phone. If you travel abroad those Blade Runner (the movie) type shops will unlock it for you free if you buy anything trivial.
Adapters cost little but you pay for those guys who buy it in bulk and resell on eBay. Same for SIM cards. US carriers don't sell SIM cards directly without anything to go with it. But somehow you can get it on eBay. Abroad, SIM cards with airtime are cheaper than refilling the airtime itself.
At any one time, only one SIM and one number is active. In the older adapters, you switch off the phone and then back on to switch SIM cards, hence your number. In the newer ones, you dial 001 and then hangup to use SIM card number one, and so on. With better compatibility, you can pick SIM1 or SIM2 on your phone menu. You can also rotate the cards at fixed intervals, x minutes for the 1st and y minutes for the 2nd. This way, you can receive all your voicemail and other alerts without having to manually switch the SIM cards. But I don't feel comfortable doing this. My adapter doesn't work in this mode anyway.
Normally you set your phone to forward on unavailable to the other number, so you will not miss any calls. But there are minor problems. You don't know if the call is forwarded or not. You just have the caller ID. So if you do not know the person, you don't know which number the caller called. And be very careful if your numbers aren't public. Your line 1 calls will be forwarded to line 2, and voice mail will be left on your line 2 account. The system default message is to announce your line 2 phone number, thought the caller called your line 1 number. The same problem occurs again if line 1 is supposed to be for John and line 2 for Peter. On the voice mail greetings you have to swap the greetings for John and Peter. But when you sometimes turned off the call forward for some reasons, you have to swap the greetings. So carrying two phones isn't a bad idea.
The cheapest way to keep an extra number this way is prepaid, roughly $100 a year or $25 for 3 months from various carriers, if you call very little. It's difficult to compare exactly because most have some refill bonus. Most carrier will allow you to go offline a few months while keeping your number. It's much cheaper if your usage patterns allow for that. AT&T (Cingular) has 3G, T-mobile still haven't make the announcement. And of course AT&T has the iPhone. With the constant cat and mouse unlock the iPhone game, no way AT&T is going to unlock your iPhone for your travels.
By the way, there are phones holding two SIM cards. But I bet they aren't too good as the demand is perhaps 1 in 1,000 or 100,000. And then there's a version of Blackberry from Verzion, which provides CDMA2000 technology, but also duals as a GSM phone for you to travel. Of course the GSM phone is unlocked for foreign carriers. And since you already picked Verizon, they are not afraid that you want to switch to GSM/3G carriers. But if money is no object, there are other more elegant ways to have a 2nd phone number with a smart phone.
The Internet or calling card like methods will be next.
Updates
For GSM and 3G(UMTS) you can play around with the SIM cards. For other carriers, you can call via some calling card like services, or Internet services.
You can buy a super SIM card, together with a card reader and writer. You copy all your carrier SIM cards over to your own super SIM card. I heard that 3G SIM's are not possible to copy due to encryption. The original SIMs have to be compatible to your super SIM and to your phone, which makes this the most problematic method, though the most elegant.
The most common method is to get a dual-SIM adapter. I think Magicsim is the most common brand on eBay and I had one, long before they have a brand name and a website online. SIM's have some sort of standards, including V1, V2 and 3G. There are also different memory sizes, 32K, 64K to 128K (3G). Make sure that your phone is on the adapter compatible list. I don' t know if it's possible that some carrier SIM's can cause further compatibility problems. But I don't think it will be if your phone is a 3G or late GSM model.
There are two types of dual-SIM adapters. The simpler type looks like three SIM cards connected together. There are two holders for your carrier SIM cards. You insert the third card into the SIM compartment of your phone. This type requires that your battery compartment isn't too tight to contain the extra thickness of the SIM cards. You are OK if your phone is on the compatibility list. I would recommend this though I had the other type.
The second dual-SIM adapter requires you to cut out the central bit of your SIM cards, and put them into a SIM card that holds your two little cut out pieces. The adapter in the form of a SIM card is slightly thicker than an ordinary SIM card, so it might not fit if your SIM compartment is super thin. Or the contact may be loose so they provide you with sponge fillers for a tight fit.
The cut out type adapters sound dangerous and difficult. It's yes or no. SIM cards don't cost much if you know where to find, and if you have a plan your carrier may replace it for you. Unless you make very stupid cuts, even if the adapter doesn't work, they provide two holders for you to hold your cards for use as if they are not cut. I advise to get a SIM cutter, which I didn't. I just used a scissor. I intended to cut a little larger than the template, then gradually reduce the size to fit the adapter. But I ended up simply chopped off the excess with one simple cut per straight edge.
The two cut out SIM cards should look exactly like two miniature SIM cards, but not mine. After a little trimming they can go inside the adapter. But with some loose space one of the miniature card can move a little inside. It didn't work at first, or it didn't work reliably. But once I swapped the two miniature cards, they fit better and never gave me problems. Maybe after a year the SIM's are lose again. So I pull out and plug in the cards again and added the sponge filler to hold the cards tighter. It works fine now.
I brought a 64K SIM served by AT&T (previously Cingular). It was another eBay order without phone and plan. It was for the GoPhone, prepaid or with a monthly plan. It might be possible that the carrier may not activate some cards, they way they are sold or according to their serial numbers. My SIMs are OK but probably because I wanted to port my old phone number to the prepaid phone(!), I went through several operators. Virgin had better service and better deal, but they are not GSM, reselling Sprint airtime.
I had a carrier unlocked GSM phone for traveling. I don't think you need an unlock phone when you are using two SIMs from the same carrier. If you ask, a nice carrier may unlock the phone for you after 6 months. But most phones are trivial to unlock yourself. For Moto you only need to download some software to the PC and a standard mini USB cable. I don't know about the latest 3G phones but you always search unlock hacks specific for your phone. If you travel abroad those Blade Runner (the movie) type shops will unlock it for you free if you buy anything trivial.
Adapters cost little but you pay for those guys who buy it in bulk and resell on eBay. Same for SIM cards. US carriers don't sell SIM cards directly without anything to go with it. But somehow you can get it on eBay. Abroad, SIM cards with airtime are cheaper than refilling the airtime itself.
At any one time, only one SIM and one number is active. In the older adapters, you switch off the phone and then back on to switch SIM cards, hence your number. In the newer ones, you dial 001 and then hangup to use SIM card number one, and so on. With better compatibility, you can pick SIM1 or SIM2 on your phone menu. You can also rotate the cards at fixed intervals, x minutes for the 1st and y minutes for the 2nd. This way, you can receive all your voicemail and other alerts without having to manually switch the SIM cards. But I don't feel comfortable doing this. My adapter doesn't work in this mode anyway.
Normally you set your phone to forward on unavailable to the other number, so you will not miss any calls. But there are minor problems. You don't know if the call is forwarded or not. You just have the caller ID. So if you do not know the person, you don't know which number the caller called. And be very careful if your numbers aren't public. Your line 1 calls will be forwarded to line 2, and voice mail will be left on your line 2 account. The system default message is to announce your line 2 phone number, thought the caller called your line 1 number. The same problem occurs again if line 1 is supposed to be for John and line 2 for Peter. On the voice mail greetings you have to swap the greetings for John and Peter. But when you sometimes turned off the call forward for some reasons, you have to swap the greetings. So carrying two phones isn't a bad idea.
The cheapest way to keep an extra number this way is prepaid, roughly $100 a year or $25 for 3 months from various carriers, if you call very little. It's difficult to compare exactly because most have some refill bonus. Most carrier will allow you to go offline a few months while keeping your number. It's much cheaper if your usage patterns allow for that. AT&T (Cingular) has 3G, T-mobile still haven't make the announcement. And of course AT&T has the iPhone. With the constant cat and mouse unlock the iPhone game, no way AT&T is going to unlock your iPhone for your travels.
By the way, there are phones holding two SIM cards. But I bet they aren't too good as the demand is perhaps 1 in 1,000 or 100,000. And then there's a version of Blackberry from Verzion, which provides CDMA2000 technology, but also duals as a GSM phone for you to travel. Of course the GSM phone is unlocked for foreign carriers. And since you already picked Verizon, they are not afraid that you want to switch to GSM/3G carriers. But if money is no object, there are other more elegant ways to have a 2nd phone number with a smart phone.
The Internet or calling card like methods will be next.
Updates
Sunday, January 6, 2008
Desktop Tower Defence - top score video cure additiction
Finally I came across something that can cure the DTD addiction. It's video on how the top scores are made. You can learn a lot, but you may also give up altogether - as I said, the game isn't great after all. So if you want to play your own way and improve at your own pace, skip the videos.
Before the video's and the analysis of the top score strategies, I can disclose some tools that may help you to have more fun. In the challenge mode, there is the 3K Fixed game. Instead of 80 gold at the start of the Hard game mode, you have 3,000, but you can't add anything afterwards. It's a fast way to test out your maze, compare your weapons, and measure the unlisted properties of the weapons, such as how much the freeze towers slow creeps down. The weapons, if available, are the same across the games, but the health of the creeps are not all the same across games.
The other useful game is the 100K Gold in the fun mode. It's the same as 3K except that you can play as in the normal mode after spending the initial gold. Even better, there are 100 levels instead of 50 in the main game, everything else being equal. So you have more gold to spend on the first 50 levels and hence more flexibility to test things out.
Finally, there's The 100 in the challenge mode. It's the same as the hard mode but with 50 more levels. So it's exactly the 100K Gold but you have only 80 gold initially as in The 100 game. The 100 doesn't help you with anything but this is simply a superset of the hard mode with more levels. You may or may not want to start with this game rather than the main game. Because the high score strategies are different - that works for 50 levels doesn't work for another extra 50.
Other modes and games are deviations from the main game. For example, some guys hate juggling, the selling and buying of the towers. It became less of a strategy game than a shoot-them game. But then there's not as much challenge because of the limitations of the game.
I used a spread sheet (Open Office) that contains data of gold earned at each level, the health of creeps at each level, and all the measurable properties of weapons, like firing rate. So you can calculate to some degree how much fire power you need at each point and if you can afford them. I also use the Open Office drawing package to help with designing mazes and acting as blue prints during the games. But with modes such as 100K, the need for these outside tools are less. Also, if you see the videos, precise optimizations are either not necessary nor not possible at the end.
I think there's some sort of collective conspiracy in the DTD forum, which missed a lot of critical information, perhaps in order to keep new players interested in the game. Firstly, as I expected, many top scores are fake. They play some other modes and hack the submission forms to change the name of the game to get impossible high scores. Or they can just hack the flash code downloaded to everybody's computer during play. So the top players started to post their fast forward video on Youtube.
The first video I recommend is a classic strategy for the main game DTD 1.5 Hard, with no juggling, or even no selling at all.
Notice it's so easy using only one Swam (6) tower and all Squirt towers. I have done similar things before but I gave up because it wasn't likely to beat the high score. The strategy is easy. I have calculated that I need the equivalent of 4 swan 6 towers to kill the air bosses. When I saw this, I went back to my spread sheet and calculated if I reduce the sw6 to 2, then I need about 7 squirt 6 towers. So I need only two boost 5 towers and one sw6 to give the equivalent of 2 sw6 towers, cheaper that way. And since building extra sq 6 towers is more economical than adding boost towers, it's pretty easy to place the sq towers without worrying packing them together to touch the boost towers. There are more than enough fire power and enough money left for two frost 5 towers to slow down the air bosses to receive sufficient hits.
As for the maze, I said that the optimum pattern for sq towers is the cross, proportional in size to their firing range. But with two or more sq packed together, the cross doesn't make much sense any more. I used the drawing package to draw range circles on each sq. I think the optimum pattern is like peeling an apple - something like the maze in the video. It's not neat, but it doesn't matter because there are more than enough fire power.
With this setup, a new player and an old player differ only in how fast they hit the send-creeps early-button to add extra scores. Very soon you will hit near the high score of this strategy. Note that the no selling is a self imposed rule. The nearest game is the 3K fixed game if you want to fight for the top spot, but 3K is easier because some bosses are less powerful I think.
The next video is the top score of DTD 1.5 Hard:
Basically the guy almost managed to send the creeps altogether, and kill them gradually long after the last creeps came out into the maze. You need always to build enough sw towers to kill the air creeps, because you can't keep them in the maze. Sq towers aren't useful to air defense at all because they will always be distracted by the land creeps. So only bash towers are useful. Since you have very little money left for it, you don't worrying how to put more of them together with boost towers.
The maze isn't that important as long as you have two alternative paths, gold efficient at the beginning, and space efficient at the end. My staggered DNA pattern works rather well, with three DNA pattern on each path, and utilizing the remaining desktop space as maze. But since you have to share the pellet towers in the two paths to save gold and space, the DNA pattern aren't necessary.
The surprise is the splash towers. Not only that they fire at everybody in range, but they are completely frozen for a long time. I gave them up because of the seemingly weak power for the money. But the freezing allows the other weapons to be many times more effective. So killing the air bosses becomes very easy.
After I saw the true master at play, I decided that this isn't my game. It's all about timing, more of a shoot-them-all game than a war strategy game. Getting the timing right initially is hard but there's not much potential to optimize.
I could have completely cured of the addiction if I hadn't see the 10K fun:
The juggling strategy for the hard mode won't work anymore over 50 levels. But, you can't survive without a little bit of juggling. So it's a balanced game. But at the end, you have to use a lot of splash towers, and reserve a large central area for all the towers. So there aren't much variation to the maze and the use of the splash towers become more of a shoot-them-all game.
Before the video's and the analysis of the top score strategies, I can disclose some tools that may help you to have more fun. In the challenge mode, there is the 3K Fixed game. Instead of 80 gold at the start of the Hard game mode, you have 3,000, but you can't add anything afterwards. It's a fast way to test out your maze, compare your weapons, and measure the unlisted properties of the weapons, such as how much the freeze towers slow creeps down. The weapons, if available, are the same across the games, but the health of the creeps are not all the same across games.
The other useful game is the 100K Gold in the fun mode. It's the same as 3K except that you can play as in the normal mode after spending the initial gold. Even better, there are 100 levels instead of 50 in the main game, everything else being equal. So you have more gold to spend on the first 50 levels and hence more flexibility to test things out.
Finally, there's The 100 in the challenge mode. It's the same as the hard mode but with 50 more levels. So it's exactly the 100K Gold but you have only 80 gold initially as in The 100 game. The 100 doesn't help you with anything but this is simply a superset of the hard mode with more levels. You may or may not want to start with this game rather than the main game. Because the high score strategies are different - that works for 50 levels doesn't work for another extra 50.
Other modes and games are deviations from the main game. For example, some guys hate juggling, the selling and buying of the towers. It became less of a strategy game than a shoot-them game. But then there's not as much challenge because of the limitations of the game.
I used a spread sheet (Open Office) that contains data of gold earned at each level, the health of creeps at each level, and all the measurable properties of weapons, like firing rate. So you can calculate to some degree how much fire power you need at each point and if you can afford them. I also use the Open Office drawing package to help with designing mazes and acting as blue prints during the games. But with modes such as 100K, the need for these outside tools are less. Also, if you see the videos, precise optimizations are either not necessary nor not possible at the end.
I think there's some sort of collective conspiracy in the DTD forum, which missed a lot of critical information, perhaps in order to keep new players interested in the game. Firstly, as I expected, many top scores are fake. They play some other modes and hack the submission forms to change the name of the game to get impossible high scores. Or they can just hack the flash code downloaded to everybody's computer during play. So the top players started to post their fast forward video on Youtube.
The first video I recommend is a classic strategy for the main game DTD 1.5 Hard, with no juggling, or even no selling at all.
Notice it's so easy using only one Swam (6) tower and all Squirt towers. I have done similar things before but I gave up because it wasn't likely to beat the high score. The strategy is easy. I have calculated that I need the equivalent of 4 swan 6 towers to kill the air bosses. When I saw this, I went back to my spread sheet and calculated if I reduce the sw6 to 2, then I need about 7 squirt 6 towers. So I need only two boost 5 towers and one sw6 to give the equivalent of 2 sw6 towers, cheaper that way. And since building extra sq 6 towers is more economical than adding boost towers, it's pretty easy to place the sq towers without worrying packing them together to touch the boost towers. There are more than enough fire power and enough money left for two frost 5 towers to slow down the air bosses to receive sufficient hits.
As for the maze, I said that the optimum pattern for sq towers is the cross, proportional in size to their firing range. But with two or more sq packed together, the cross doesn't make much sense any more. I used the drawing package to draw range circles on each sq. I think the optimum pattern is like peeling an apple - something like the maze in the video. It's not neat, but it doesn't matter because there are more than enough fire power.
With this setup, a new player and an old player differ only in how fast they hit the send-creeps early-button to add extra scores. Very soon you will hit near the high score of this strategy. Note that the no selling is a self imposed rule. The nearest game is the 3K fixed game if you want to fight for the top spot, but 3K is easier because some bosses are less powerful I think.
The next video is the top score of DTD 1.5 Hard:
Basically the guy almost managed to send the creeps altogether, and kill them gradually long after the last creeps came out into the maze. You need always to build enough sw towers to kill the air creeps, because you can't keep them in the maze. Sq towers aren't useful to air defense at all because they will always be distracted by the land creeps. So only bash towers are useful. Since you have very little money left for it, you don't worrying how to put more of them together with boost towers.
The maze isn't that important as long as you have two alternative paths, gold efficient at the beginning, and space efficient at the end. My staggered DNA pattern works rather well, with three DNA pattern on each path, and utilizing the remaining desktop space as maze. But since you have to share the pellet towers in the two paths to save gold and space, the DNA pattern aren't necessary.
The surprise is the splash towers. Not only that they fire at everybody in range, but they are completely frozen for a long time. I gave them up because of the seemingly weak power for the money. But the freezing allows the other weapons to be many times more effective. So killing the air bosses becomes very easy.
After I saw the true master at play, I decided that this isn't my game. It's all about timing, more of a shoot-them-all game than a war strategy game. Getting the timing right initially is hard but there's not much potential to optimize.
I could have completely cured of the addiction if I hadn't see the 10K fun:
The juggling strategy for the hard mode won't work anymore over 50 levels. But, you can't survive without a little bit of juggling. So it's a balanced game. But at the end, you have to use a lot of splash towers, and reserve a large central area for all the towers. So there aren't much variation to the maze and the use of the splash towers become more of a shoot-them-all game.
Friday, December 21, 2007
Desktop Tower Defence - not so great after all
After some scientific research, the whole game is reduced into a spread sheet. There are not enough randomness to sustain the game. Only the spawn creeps have some randomness in the way they spawn into several smaller creeps. Also the creeps are dumb. Once you figure out a good way to kill the creeps, they are all dead sooner or later. The mazes don't make a lot of difference when at the end it's all about fire power.
Most weapons are smoke screens on the hard mode for example. You have little choice on a few of the useful weapons.
After I killed all the creeps with ease, I researched how the highest scores are achieved. I think they are smoke screens too. The scores with videos to back up aren't that high. I think many high scores in the scoreboard are categorized by mistake or deliberately. I looked at the associated mazes. Though mazes don't tell you the full story because it's a snapshot of the final moment, but some mazes contain too much money in it for the hard mode. Maybe the money is possible at the very end, but then it's unrelated to how to pass the most difficult stages.
After so long, I should think the highest score gurus would have come out to explain how they invented the winning strategy and earn the bragging right. Perhaps they want to keep it a secret because the game is so simple. Once they tell you everybody know how to beat it with ease, unlike every other console games. Perhaps the scoreboard is really one big smoke screen to keep people playing.
The challenge mode and fun mode are giveaways. The game itself doesn't have that much variation. By using totally different rules, you are playing different games when the original game is done and dead.
Killing all creeps gives you about 7,000 points. If you send the creeps earlier you earn more points. These extra points are about linear, more or less the same at every level. So to get some of the high scores, almost you have to send all creeps at once, which isn't possible. I estimated the max scores possible is about 10,000. I don't know how some 14,000 can be achieved in the hard mode.
So this is my final take on the game, unless some guru come out and explain how they earn high scores. And it have to be interesting, that is, related to real war strategy.
Swarm tower: it's much more efficient for air defense than squirt towers. It had to be at the dead center of the desktop. When you have two, put the 2nd one next to the dead center. The upgrade sequence is simple. When you are at level 7xN, your tower should be SW N. But you don't need any swarm for the first flying creeps when N=1. This assumes that you have a strong enough squirt tower to help with air defense, not busy with other creeps.
For level 7x7, you need two equivalent sw6 towers, such as one sw6 touching two bo5 (50% boost) towers. For level 7x8, flying bosses, you need the equivalent of four sw6 towers, such as two sw6 touching four bo5 towers. Also for the flying bosses you need two frost towers, fr6, to cover both boss.
There could be variations that I didn't exhaust. If you only slow down only one boss, each boss in theory absorb twice the fire power. I did tried with one fr6 to slow down one boss. It worked pretty good but not very consistent. If you need two fr6 to slow down one boss, it doesn't save you $250. You can have five bo5 (maximum boost towers) touching one sw6. It's not too good but it works better with an extra sw5 touching four bo5. I didn't exhaust all these, but the money saved doesn't seem to be that great, so you don't gain a lot of fire power for the other creeps.
You need only one bash tower, the priority of upgrade. It kills all creeps all at once passing through, the strategy to have high scores by sending the next wave of creeps early. But you cannot have bash alone because they cannot kill any boss for their short range. The best "maze" for bash is the cross but degenerates into one square block, and you try to surround the bash so creeps have to run along it on all four sides. See DNA defense in earlier post. But this conflicts with boost towers, which has to touch the bash.
The compromise for the bash maze is for the tower to touch two (or even three) boost towers. There are still three sides for the creeps to run along. This still look somewhat like the DNA defense.
You need only one squirt tower. You need a long range weapon to kill the bosses, and certainly the spawns. It's sufficient if this tower is boosted by two (or three) boost towers. The best maze is a cross three square in width initially, and five square in width at the end. You force the creeps to run around your cross. Your cross have to be small to survive the initial attacks with little money, and enlarging your cross is easy and cheap to do, but very effective. You should integrate one corner or one side of the cross with the bash maze.
You upgrade your squirt along with the bash. You need a spread sheet to be optimum. But simply put, you upgrade when you have money, bash first, until you bay $290 for the squirt before $260 for the bash. And it doesn't matter that much if you are good.
So you have one bash, one squirt, and one swarm. When they are all upgraded to the full, you try to touch them as much as possible with 4 or even more boost towers. When you get to the flying bosses, you need in addition one sw6 touching 4 bo5, and two fr6 covering each flight path.
You also need the so called juggling to send the creeps back and forth at some point. With my sufficient fire power, you can keep juggling to a minimum. Juggling means you don't have good design and enough fire power. The creeps will accumulate and divert fire power if you juggle too much.
For the last two bosses, you must send them out together, so no remaining creeps are to be released. All maze blocks part of the creep's entrance so they are forced into the heart of the maze. When no more creeps are released, you can just unblock the entrance, and block the exit of the maze, so the creeps have to go all the way back to where they started. For a good design they will be killed before they reach the entrance. There are no extra maze needed for juggling.
The only other case you need juggling is for the spawns, especially for the bosses at level 48. But since the next creeps are flying with no more creeps coming out for a long time, you can do the same as the final bosses. But if the spawns aren't killed soon enough, the squirts will be diverting fire power from the flying creeps. Anyway, a little juggling can save you a lot of money for other things. In practice, you need to add a little extra maze such as the DNA pattern to slow down the creeps at the entrance and exit, to give you enough response time to sell and buy blocks.
One possible variation, if boosting the frost towers further slow down the creeps, it would be very useful. But I doubt it, the game isn't that complicated, such as that the boost towers don't boost each other. And if the slow down can be boosted, the game would be too easy.
Most weapons are smoke screens on the hard mode for example. You have little choice on a few of the useful weapons.
After I killed all the creeps with ease, I researched how the highest scores are achieved. I think they are smoke screens too. The scores with videos to back up aren't that high. I think many high scores in the scoreboard are categorized by mistake or deliberately. I looked at the associated mazes. Though mazes don't tell you the full story because it's a snapshot of the final moment, but some mazes contain too much money in it for the hard mode. Maybe the money is possible at the very end, but then it's unrelated to how to pass the most difficult stages.
After so long, I should think the highest score gurus would have come out to explain how they invented the winning strategy and earn the bragging right. Perhaps they want to keep it a secret because the game is so simple. Once they tell you everybody know how to beat it with ease, unlike every other console games. Perhaps the scoreboard is really one big smoke screen to keep people playing.
The challenge mode and fun mode are giveaways. The game itself doesn't have that much variation. By using totally different rules, you are playing different games when the original game is done and dead.
Killing all creeps gives you about 7,000 points. If you send the creeps earlier you earn more points. These extra points are about linear, more or less the same at every level. So to get some of the high scores, almost you have to send all creeps at once, which isn't possible. I estimated the max scores possible is about 10,000. I don't know how some 14,000 can be achieved in the hard mode.
So this is my final take on the game, unless some guru come out and explain how they earn high scores. And it have to be interesting, that is, related to real war strategy.
Swarm tower: it's much more efficient for air defense than squirt towers. It had to be at the dead center of the desktop. When you have two, put the 2nd one next to the dead center. The upgrade sequence is simple. When you are at level 7xN, your tower should be SW N. But you don't need any swarm for the first flying creeps when N=1. This assumes that you have a strong enough squirt tower to help with air defense, not busy with other creeps.
For level 7x7, you need two equivalent sw6 towers, such as one sw6 touching two bo5 (50% boost) towers. For level 7x8, flying bosses, you need the equivalent of four sw6 towers, such as two sw6 touching four bo5 towers. Also for the flying bosses you need two frost towers, fr6, to cover both boss.
There could be variations that I didn't exhaust. If you only slow down only one boss, each boss in theory absorb twice the fire power. I did tried with one fr6 to slow down one boss. It worked pretty good but not very consistent. If you need two fr6 to slow down one boss, it doesn't save you $250. You can have five bo5 (maximum boost towers) touching one sw6. It's not too good but it works better with an extra sw5 touching four bo5. I didn't exhaust all these, but the money saved doesn't seem to be that great, so you don't gain a lot of fire power for the other creeps.
You need only one bash tower, the priority of upgrade. It kills all creeps all at once passing through, the strategy to have high scores by sending the next wave of creeps early. But you cannot have bash alone because they cannot kill any boss for their short range. The best "maze" for bash is the cross but degenerates into one square block, and you try to surround the bash so creeps have to run along it on all four sides. See DNA defense in earlier post. But this conflicts with boost towers, which has to touch the bash.
The compromise for the bash maze is for the tower to touch two (or even three) boost towers. There are still three sides for the creeps to run along. This still look somewhat like the DNA defense.
You need only one squirt tower. You need a long range weapon to kill the bosses, and certainly the spawns. It's sufficient if this tower is boosted by two (or three) boost towers. The best maze is a cross three square in width initially, and five square in width at the end. You force the creeps to run around your cross. Your cross have to be small to survive the initial attacks with little money, and enlarging your cross is easy and cheap to do, but very effective. You should integrate one corner or one side of the cross with the bash maze.
You upgrade your squirt along with the bash. You need a spread sheet to be optimum. But simply put, you upgrade when you have money, bash first, until you bay $290 for the squirt before $260 for the bash. And it doesn't matter that much if you are good.
So you have one bash, one squirt, and one swarm. When they are all upgraded to the full, you try to touch them as much as possible with 4 or even more boost towers. When you get to the flying bosses, you need in addition one sw6 touching 4 bo5, and two fr6 covering each flight path.
You also need the so called juggling to send the creeps back and forth at some point. With my sufficient fire power, you can keep juggling to a minimum. Juggling means you don't have good design and enough fire power. The creeps will accumulate and divert fire power if you juggle too much.
For the last two bosses, you must send them out together, so no remaining creeps are to be released. All maze blocks part of the creep's entrance so they are forced into the heart of the maze. When no more creeps are released, you can just unblock the entrance, and block the exit of the maze, so the creeps have to go all the way back to where they started. For a good design they will be killed before they reach the entrance. There are no extra maze needed for juggling.
The only other case you need juggling is for the spawns, especially for the bosses at level 48. But since the next creeps are flying with no more creeps coming out for a long time, you can do the same as the final bosses. But if the spawns aren't killed soon enough, the squirts will be diverting fire power from the flying creeps. Anyway, a little juggling can save you a lot of money for other things. In practice, you need to add a little extra maze such as the DNA pattern to slow down the creeps at the entrance and exit, to give you enough response time to sell and buy blocks.
One possible variation, if boosting the frost towers further slow down the creeps, it would be very useful. But I doubt it, the game isn't that complicated, such as that the boost towers don't boost each other. And if the slow down can be boosted, the game would be too easy.
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