Franc Zabkar wrote in message
...
On Sun, 20 May 2012 09:31:43 +1000, Franc Zabkar
put finger to keyboard and composed:

On Sat, 19 May 2012 13:52:58 +0100, "N_Cook" put
finger to keyboard and composed:

I now see someone else has been here before and ground off IC5

music-electronics-forum.com/t10881/

Did you see the following post in that thread?

================================================= ===================
Have you noticed that pins 1 and 4 (Vcc and COM) of IC5 are reversed
on the schematic (if this is IR21531)?
================================================= ===================

Sorry, I should continued reading. It appears that they are indeed
reversed.

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


Just checked again
The polarity pip of the original was not ground off and p1 is connected to
the dropper from the + of the HV dc caps , ie Vcc and p4 is connected to the
zero/negative of the HV caps (not ground of course) . So someone getting his
pin convention wrong I think, overlay "pip" is obscured by the chip and
agrees with the original orientation of the chip