09-12-2018, 06:56 PM
Hi Bob,
I can't offer much advice regeading a PCB layout for your valve amp, but I've had a look at the schematic and was very suprised to see the very low values of interstage cooupling capacators used. I've no idea of the intended purpose of your amp and I havn't done any calculations but I suspect the low frequency response will be quite poor. I did a quick google search on similar circuits and something in the region of 0.iuF would be more typical, I think my amps use 0.5 uF or thereabouts.
wrt the circuit board, in general keep the grid circiits away from anthing else and use a common ground point.
hth David.
I can't offer much advice regeading a PCB layout for your valve amp, but I've had a look at the schematic and was very suprised to see the very low values of interstage cooupling capacators used. I've no idea of the intended purpose of your amp and I havn't done any calculations but I suspect the low frequency response will be quite poor. I did a quick google search on similar circuits and something in the region of 0.iuF would be more typical, I think my amps use 0.5 uF or thereabouts.
wrt the circuit board, in general keep the grid circiits away from anthing else and use a common ground point.
hth David.
