4 pill comp amp question

[psycho]

The output transformers have 1 toroid with 3 wraps feeding 12V to the back of the transformers.....2 2 pill sections 1 wrapped toroid each.
What is the function of the 2 wrapped toroids from the copper board to the input transformers ....I ask this because this is the only comp amp I have ever seen that does not have them. Amp seems to work pretty good any way.
No I don't have a clue who made this amp since I got a few amps on a trade.

 

[543_Dallas]

The wire the wire from input transformer to the copper board grounds the bases of the transistors. The amp is class C. The torrid cores with 3 wraps are RF chokes. The wire has a low DC resistance and high RF resistance.

The collector of the transistors are fed 12v + via the output transformer. The torrid core also acts as an RF choke to keep as much RF as possible off the 12v + line.

 

[psycho]

The wire the wire from input transformer to the copper board grounds the bases of the transistors. The amp is class C. The torrid cores with 3 wraps are RF chokes. The wire has a low DC resistance and high RF resistance.

The collector of the transistors are fed 12v + via the output transformer. The torrid core also acts as an RF choke to keep as much RF as possible off the 12v + line.

I wonder how it works without the transistor bases grounded...I guess I'll need to add them.
Thanks for the explanation.

 

[psycho]

Looks like a nice build, here is the input that caught my attention.

 

[543_Dallas]

Don't know why he left them out. The pic looks a little rough on my phone but from what I can see I think he should have installed the chokes to ground. Maybe his watt meter moves more without them. The transistors will still work as long as the emitter (tabs on the side) is grounded.

 

[dx31353]

I would replace the caps across output with these

http://www.icamanufacturing.com/store/p/187-CAP-M-1000.aspx

I would also add two of these to the power bus

http://www.icamanufacturing.com/store/p/219-CAP-A-4700.aspx

Also the disc caps on the bus look small. What value are they.

Out of curiosity what is the value of the input and output caps?

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[dx31353]

I don't know if this will make any difference but I have always seen three wraps on the chokes from the output transformers to the power bus.

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