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Therealporkchop
Intermediate Member
Username: Therealporkchop
Post Number: 426
Registered: 11-2002
| | Posted on Thursday, October 27, 2005 - 12:33 am: | 
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Ok, read carefully and offer your two cents...
Ok, I don't know how many of you out there have this box and have been stupid enought to try this...but here's what I've done and I need some advice.
OK, the box comes with 4-1446 transistors. Well, not being able to leave well enough alone, I swapped them all out for 2879's. I started to go with 2290's, but a good friend talked me outta that one.
OK...changed them out and there are only two adjustable capacitors inside, so I've tuned and twisted on them and I still only see about 500 watts total from the box. That's a PEP reading by the way, and the RMS reading is less than what I expected at around 150-175 watts, but that could be my crappy meter.
I know there are other capacitors I need to change, the only problem is I'll have to order them and I don't want to order something I don't need right now. The transformers that use the 4 ferite cores have a 560pf cap bridged across them. What should I change this to? I know this is the most important one to swap out first. Then there are the four that I assume bridge the collector to the emitter that I think are around 160pf each. Should I change them too?
Now on the power supply side, I cranked it up to 19.5 volts, and this alone I thought would have yielded a higher power output. But so far, it hasn't.
So what's the dealy'o? |
Slowhand
Intermediate Member
Username: Slowhand
Post Number: 101
Registered: 7-2005
| | Posted on Thursday, October 27, 2005 - 4:29 am: |
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You'll have to rewind the ferrite transformers also. Get the schematic for an amp with 2879's and copy the values into your amp. |
Thehobo
Junior Member
Username: Thehobo
Post Number: 21
Registered: 2-2004
| | Posted on Thursday, October 27, 2005 - 5:27 am: |
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say hey P.C., i think what your up aginst is the voltage regulator in the amp?? also i dont believe the power supply is big enough to run the bigger pills?? for all the work involved, the gain is not going to be that much!! the boomer 500 i have i run with a well tuned 2950dx and i get about 5 to 600 on my palstar 150 base meter, thats on ssb, on am it stays around 500+ at times!
althou you turned up the power supply, i still think the internal V/R, is holding it down?? this is also the weakest point in this amp combo??
hope i helped some..
thehobo
274150 am
monitor ch. |
Therealporkchop
Intermediate Member
Username: Therealporkchop
Post Number: 433
Registered: 11-2002
| | Posted on Thursday, October 27, 2005 - 11:43 pm: |
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Yeah, I've been thinking I should try to copy the Texas Star 667, but was waiting for suggestions.
I seperated the amp totally from the power supply and ran it straight off two batteries tied together and running a big charger on it. I still can only get a tad over 400 right now. So yes, I agree, that I will need to change a few other things. I was just wondering which things I needed to change.
I think the power supply will handle it myself. Although it's only 35 amps, I think that would really apply to the RMS side and not the PEP side. On the meter I've been using, every amp I've hooked up only puts out around 150 - 175 watts RMS. So if I believe this meter, that means that there is no amp in the world that will swing past 175 watts RMS. HAHA. Yeah right...
Anyway, when I get more time, I'll drag out the schematic for the TS and try that once I order up some parts. Copper should offer packs with all the parts needed for such an experiment...
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