• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

DIY High power Audio Amplifier from Heathkit SB200

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I bought an old Heathkit SB200 Linear amplifier. I want to modify it become a
High power Audio Amplifier. A technical man said me that add 2 x 6V6 tubes into this machine (driver stage) and modify the machine schematic ?
I wonder : 1. Will it be a good and high power audio amplifier ?
2. What is the good parameters of the tube audio output transformer ?
3. Can we decrease the high Mu voltage for the 2 x 572B tubes when modify the amplifier ?
Any one can help me some ideas ?
An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.
 

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The sensible thing to do is sell it to someone who can make use of it in its proper state, and use the money to buy audio stuff.

It is designed to use a high voltage supply, much higher than a normal valve audio amp. Very dangerous, except for those who really know what they are doing. I suspect, from your questions, that this is not a safe project for you - even if it was a sensible project which it isn't.
 
The more acknowledge - the cheaper tube amply I will have

I attend to hire a a technical man does it for me, but I think if any body help me some opinion I will have the best solusion and save much money. Thank you. Please help me, Brothers. In addition, in Vietnam we are not allowed to play the radio waves. I have to modify it for audio amplifier.
 
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it ridiculous to try and convert it to an audio amp. B+ is around 1000volts. Hardly any of the circuitry could be reused. There is no output transformer - where would you get one and where would you put it - plus it's mono!!!! And the tubes may not be that linear - what would you drive it with. It is probably worth around $500US. Sell it

Charles (K1ETU)
 
All parts are be ready

I have the heathkit SB200, 2 * 6V6 tubes, 12 kgs of large EI silicon steel using for winding 2 single end output transformers. I would like to build an speacial high power tube amplifier. I found some man had builded 811A and 813 SE tube audio amplifiers with hundreds of watt. Why we cannot? Please help me.
 
All parts are be ready

I have the heathkit SB200, 2 * 6V6 tubes, 12 kgs of large EI silicon steel using for winding 2 single end output transformers. I would like to build an speacial high power tube amplifier. I found some man had builded 811A and 813 SE tube audio amplifiers with hundreds of watt. Why we cannot? Please help me.
 
Wow... look at that tank coil and those tubes. I am no pro at this, but this thing was designed for pretty much one single purpose and that is to power signals over the air. This is not an audio amp.

To make it into an audio amp? Well, you might be able to use the enclosure and maybe the on/off switch and that is about it. And the knobs.

If you want to make an audio amp like a simple SE tube amp (okay forum members, don't bite my head off -- I am going real basic), then here is a list of what you need to start: for stereo, you'll need two output transformers, one power transformer, a couple of output tubes (triodes or pentodes), one gain tube, bases for the tubes, various electrolytic caps, wire, someresistors, and either a silicon or tube rectifier.

Or you could sell it for $300 and use that money and build a nice sounding low parts count chipamp instead.
 
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There are plenty of tube guys in Vietnam to help you, this RF linear amplifier is not a suitable device to build an audio amplifier out of. Sell it on eBay and build something safe and suitable for audio. It's worth good money, people actually collect these, and selling it will get you more than enough money to build something suitable.
 
I would have said it's like taking an old Ferrari and turning it into a tank, but oh well... great minds think alike, eh? ;)

Seriously, the OP has been given some good advice. Besides, judging from the pics, I'd say that the unit in question is in excellent condition - even more reason to put it up on eBay, as it would likely fetch a tidy sum. If that's indeed where the OP bought it to begin with, he could still get his money back and buy the parts for a very solid amp.

572B's, while relatively cheap, require pretty high voltages to work properly. They also appear to have pretty lousy curves from an audio standpoint.

Any funds made by selling that linear could perhaps go toward parts to build a 6550 SE amp or the like, which produce listenable results at much more sane voltages.
 
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