| Author |
Message |
    
snapperhead
| | Posted on Wednesday, February 27, 2002 - 1:42 pm: | 
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I have a Texas Star DX400 high drive with variable. It's pretty tired. I opened it up and it has 4 toshiba 2SC2290's in it. Is it possible to kick it up to a 500w or more? And if so how? |
307
| | Posted on Wednesday, February 27, 2002 - 9:05 pm: |
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It is definatly NOT worth attempting it for a small gain of 100 watts. It takes a bunch to do. Buy a bigger amp...
307 |
Warlock
| | Posted on Wednesday, February 27, 2002 - 9:20 pm: |
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The best improvement to those amps is removing the factory power and ground wire and replace it with fine stranded 8ga wire, bypassing the internal fuse. |
Snapperhead
| | Posted on Thursday, February 28, 2002 - 12:22 am: |
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Hey guys, thanx for amp tip. Warlock, Question: Is the internal fuse the two fuses in back of Radio? and once I bypass with 8ga wire do I run some other kind of fuse inline, that comes off the battery? Phil(Snapperhead) Reno, Nv. |
Warlock
| | Posted on Thursday, February 28, 2002 - 5:46 am: |
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The fuse(s) mentioned are in the amp, and after upgrade you will need to fuse at the battery with a 50a fuse. |
Biged
| | Posted on Thursday, February 28, 2002 - 7:51 pm: |
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What do the fuses look like? I upgraded my 400 HD with 8 ga power wire and just soldered it to where the 14 ga existed.I didnt see anything that resembled a fuse. |
Warlock
| | Posted on Friday, March 01, 2002 - 5:16 am: |
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Some amps come with the fuse in the power wire outside the amp. The TS amps have an internal fuse. The power wire comes in the case, to the fuse, then to the board for supply. |
Snapperhead
| | Posted on Tuesday, March 05, 2002 - 9:18 am: |
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Hey Warlock, Thanks for tip. I replaced stock pos wire with 8g and by passed fuses, soldered right to board. I also replaced neg wire with 8g wire. Since I don't have a fuse now. I put 50amp inline fuse off of battery. I did notice a wattage increase on my meters. About 50watts. Thanks again
(Snapperhead) |
975
| | Posted on Thursday, March 07, 2002 - 10:50 pm: |
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Ok here's an idea for you, look inside of the amplifier, there should be a total of four 2SC2290's in there. you can change them to 2SC2879's, and get about 750-800 watts PEP out of the unit, calculated by 120 watts a transistor, times 4, which is 480 watts RMS, which would be 720 watts PEP, plus given the fact that the gain characteristic of the transistor is higher at 27Mhz than 36Mhz which it is tested at. Be careful when you do this to keep your soldering neat, use a fairly high wattage iron for the transistor leads, and make sure they are mounted BEFORE soldering them, to prevent heat damage, and cracking the leads when tightening the mounting screws. You can get a matched set of four 2SC2879's from R.F. Parts, at 1-800-RF-PARTS, or at www.rfparts.com |
Warlock
| | Posted on Friday, March 08, 2002 - 10:23 pm: |
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I'd like to know how it is you can take a TS DX400, remove the 2290s and replace them with 2879s and see more than a 15% gain?
Not only are there capacitance changes necessary, but the output transformers will saturate in an instant from the higher gain of the 28s and yeild little added power output.
Sure, it can be done, but to be done correctly you'd probably invest (waste) around $200. It's cheaper to sell and buy different. |
jyd
| | Posted on Saturday, March 09, 2002 - 8:59 am: |
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you have to upgrade more than the trasisters to get more power. |
Bigbob
| | Posted on Saturday, March 09, 2002 - 3:55 pm: |
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Go to communications electronics and get 2 diplexers then buy 3 more dx400s and you'll have a 6db gain,oh you better get a lot more batterys.hmmmm. |
Bigbob
| | Posted on Sunday, March 10, 2002 - 9:27 pm: |
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My mistake comm.electronics is not the place for diplexers,I lost the website,it also had plans for medium and high power mobile rf amps.These amps had trimmers for bias and copper heat spreaders I sure would like get to that web site again. |
ss8541
| | Posted on Monday, March 11, 2002 - 12:03 am: |
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not sure of the address, but i am almost positive that the company that you are refering to is communication concepts inc. if not, they also carrier these same products. |
Bigbob
| | Posted on Monday, March 11, 2002 - 7:12 pm: |
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Thanks alot ss8541,muchous gracias. |
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