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donkeystomper amps

No not all transistor amps are class c
Amps can be built as you want.
Yes you can take a class c amp and bias it for AB.
The reason that the amps for shoot outs (aka completion amps ) were built class C with 2879 transistors is because you can get more watts per out the back for the amount of current draw, you can volt the shit out of them, you can seriously over drive them.

These amps were never ment to be daily driver amps, they were built for the Keydown crowd, but when guys started winning belts and trophys with them at shoot outs everyone wanted one.
This started a trend torward running comp amps for every day use.
Yes they work.
But even on AM they are not the cleanest thing.
Then, guys want to run them on SSB were even more problems pop up.

And if I bought a Amp off of Flea bay described as class AB and got a c comp box it would go back.
But I would want lots of pictures of the amp for sale and ask a bunch of questions before throwing down my cash.
Most of the amps I have now were bought from a seller I knew and could trust.
Buying CB Style amps on fleabay is a crap shoot now days even if they are new.

73
Jeff
 
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AudioShockwav said:
Regulated voltage with a diode in contact with the transistor to track heat is better than the Diode/ Resistor set up like is used in Texas Star.
I agree with 453.
That is a class C amp.
Another Comp box.

73
Jeff
Click to expand...
Hello Jeff: Ok good deal thanks, I think I can make one up with a little trill and a lot of error.

Jay in the great Mojave desert
 
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Jay there is some good stuff on the internet about building bias set up into transistor amps.
I am not home so I don't have any links I can post for you but if you dig a little you can find them.

73
Jeff
 
PB
Depends on how bad the signal going into the amp is.
If it is a badly hacked radio it can get crappy.
I sound like a old shit and hate comp amps but I get it.
Kind of like a guy that runs nitrous on his street car, guys like to play AM and that is why they are there.
My view point is....
I look at things from a 80% SSB user level, the rest on AM.
I want to have a clean radio and a amp that just amplifies that clean signal.
So I want some proper bias.


I will give 44 props for a nice looking build on the 5 pill.
You got to remember back in the day you did not even see negative feedback on this style amp.

73
Jeff
 
2NC995 said:
No comments on the solder, lol.

It’s not even wetted to the board.

View attachment 32649 View attachment 32650 View attachment 32651
Click to expand...
I have pointed this out in another thread. The most important connections related to amplifier stability are totally compromised by using copper sheet metal which conducts heat so fast that it makes soldering the emitter ground connections nearly impossible. He basically mounted a copper heat spreader on a heatsink and then expected to properly solder to it. Current may even be pulled in series now through other transistors that are grounded.
 
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Unit 75 said:
Here is a better pic of his amp View attachment 32670 for you
Click to expand...
Notice how much care was taken to insure every picture does not show the center tap of the input transformers, DC ground connection through the RF choke? Almost like he wants you to think it's not soldered to ground and could be connected to a bias line. That's all I was looking for to determine class C but the absence of any other bias wire or circuit in the area insures it is class C and the other end of the choke is soldered to ground.
 
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To drag this one up from the grave......
I've been running a Donkey Stomper 500V-HG (1x4) for close to 1.5 months now and have been very pleased with it (considering my disappointment with TS, it wouldn't take much). The readings in the video of my amp match mine, give or take 50 watts. I haven't cracked her open to look at the work because honestly, it's working great so I don't want to jinx it, but what I can see through the fan cutout looks very neatly done. Another thing I like, if I message him on facebook with a question, he responds pretty quickly. He warranties everything but the pills for 30 days from time of delivery plus he post vids of the amp in operation so you know what to expect.
 
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