Franc Zabkar wrote in message
...
On Fri, 18 May 2012 08:49:52 +0100, "N_Cook" put
finger to keyboard and composed:

I suppose for this amp only used in 240V land, then replacement SMPS
driver
powerFETs only need to be rated 600V/10A and for such an amp only in
100/110/120V land then 300V/20A rating

JP1 in the bridge rectifier area configures the unit for 240VAC
operation when open, and 120VAC when closed. In the latter case the
circuit becomes a voltage doubler.

Therefore Vdc = 350VDC in both configurations.

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.


So that 220/220V zener chain is perhaps more for the possibility of someone
jumpering JP1 to 100V and plugging in to 240V and instead of 350V dc trying
to get to 700V dc

Have got inundated with more normal stuff and this Mark will have to wait a
few days