Yah its me that posted the mod advice for the 200S way back. You can go with that approach, or use an SDS board too. I have an SDS board for my Dynaco Stereo 70 and its good quality. I completely rewired my 200S and isolated all grounds from the chassis so I could change the grounding scheme, so in my application, the discrete caps were a better choice than the SDS board. Whichever way you go, the larger cap values in the power supply make for a better amp for bass by a longshot. The end result for this mod should be 110uf, 50uf, 20uf, 20uf, using caps wired in series for the first two stages to get a high enough voltage rating, and the 3rd cap should be a 500v cap. This requires 220uf 350v caps wired in series with 220k 1w resistors in parallel with each cap to get that 110uf value. A similar thing for the 50uf value with two 100uf caps in series and the resistors also. Using a replacement for the can isn't a good idea because it is only rated to 525v and the amp puts out more like 560v. Do a search in the archives for my old post on it as it goes into all the details.
If your power light works, then the power transformer is working. The output transformer could be blown, in which case Triode Electronics sells excellent replacements. The polarity switch is not needed with a 3 wire grounding system like modern electronics uses. I put mine to use as a ground lift switch, but as I said, the whole amp has to be rewired to make this work. You could just disconnect it if you change over to a proper 3 wire grounding system. If you need to know how to do this, there is info at other forums in the archives like the Hoffman amp forum for instance, or someone could type it here too. If you don't know what you're doing in regards to working on high voltage tube amps, you should learn before messing with it, or take the amp to a qualified tech as it is dangerous and can kill you.
Greg
