From Bob Weigel Sent Fri, May 6th 2005, 17:51
From Bob Weigel Sent Fri, May 6th 2005, 17:51
Yes power supply capacitors are the hot tip I'd think for that one. If you don't have an ESR meter to check them then pull one of the big ones and just see. Could be something else heating up but it sounds like an effect that isn't oriented towards one particular section of circuitry kind of :-). -Bob Andre Majorel wrote: >On 2005-05-06 12:00 +0100, Peter Forrest wrote: > > > >>Can anyone offer suggestions to cure a bizarre fault on a PS-3300? >> >>The instrument plays fine, and sounds wonderful..... for about ten >>minutes. Then, if a three or four note chord is played, it goes >>berserk. Lots of notes trigger at random. A great abstract >>sound....... but...! >> >>Switching the machine off then on after 10 - 30 secs brings the power >>light on, but no sound and NO LEDs flashing. >> >>Switching it off and on again after that usually gets it working >>properly again....... but only for 5-10 minutes before the next crash. >> >> > >I would venture that the power supply is marginal and, as you >play more notes at the same time, the current draw increases >slightly, enough to throw the PSU off. If it takes several >minutes to happen, it may be heat-related. > >I'd start by checking that the PSU puts out the intended >voltages and what happens to them when the problem occurs. How >hot are the voltage regulators and rectifier bridge ? > > >