12-12-2019, 06:35 AM
Got you lads re oscillation. If you look at the pics grid stoppers are tight on the pins and checked the OP with a PC SA, several in fact inc Audacity, there's no HF oscillation just 2nd harmonic @ around 40dB, 3rd 10dB below that. THD is 0.5% @ 1khz/5.4v RMS OP, noise is 0.004v RMS. Frequency response could be better, but with this amp I wasn't striving for anything too mad, I wanted a bit of 2nd harmonic.
I was thinking of applying a bit of global NFB, but would that ruin the OP Z? AFAIK it should improve it.
Nice fettling Tracy, I like that style of HS/Q fixing, some nice capacitors too. I like using pins too for the IP's/OP's but use turret tags, it makes removing the board easier.
Andy.
I was thinking of applying a bit of global NFB, but would that ruin the OP Z? AFAIK it should improve it.
Nice fettling Tracy, I like that style of HS/Q fixing, some nice capacitors too. I like using pins too for the IP's/OP's but use turret tags, it makes removing the board easier.
Andy.
