The Mark II uses the same board layout as the Mark III which is here > Board layout Mark II/III
Check with Kevin at Dynakitparts. He should have the board layout for the Mark IV.
Bob
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Bob Latino wrote:Dynaco never gave a parts layout on their PC-3 driver board for the ST-70. They also never listed the parts that were on the driver board in the main parts list for the amp on page 11 of the ST-70 assembly manual. ....
Bob Latino wrote:scsidude2 wrote:Thanks for all the help Bob, i just installed the new caps and it sounds great! I was wondering what your recommendation was for the two 50 MFD caps on the terminal strip under the right channel output transformer as to what would be a good upgrade for them? Thanks again! -Ryan
Hi Ryan,
I think you mean the 7 lug terminal strip under the LEFT output transformer.
Those 50 uF caps on the 7 lug terminal strip are only looking at maybe 70 VDC. Any two 47 to 50 uF electrolytic caps at 100 volts or higher would work fine here. Just make sure that you have the polarity correct on these two caps. The "+" end of each cap goes to lug 1 and on the two "-" ends, one goes to lug 3 and one to lug 4. See pictorial below ...
Bob
WireNut wrote:The amp that is due to arrive tomorrow has the SDS Labs board, can I/should I up the coupling cap value to 2.2 like was suggested earlier on this post? If so, should I increase the .47 to 1.0?
WireNut wrote:Ooops, I meant .22, thanks for the advice and correction!
What about the two .47?