Re: Need help: DSD-440 with unresponsive formatter/control board

On Sep 20, 2016, at 2:02 PM, Julian Wolfe wrote: > > After reading this section, I should probably bring up that when I checked > the PSU voltages, the 5v+ line was low, at 4.7v or so. I adjusted it back to > 5.05v on the pot as defined in the manual, and there it stayed

Re: Need help: DSD-440 with unresponsive formatter/control board

After reading this section, I should probably bring up that when I checked the PSU voltages, the 5v+ line was low, at 4.7v or so. I adjusted it back to 5.05v on the pot as defined in the manual, and there it stayed steady, but it didn't seem to help. Before I adjusted the pot, it was

Re: Need help: DSD-440 with unresponsive formatter/control board

On Sep 20, 2016, at 1:37 PM, Julian Wolfe wrote: > > Both green LEDs are on. They're ALL on. > > As LED 9 is on (sorry for not being clear), then the CPU is active. That’s a good sign. Definitely look at the DC Power up/down circuit first. Jerry

Re: Need help: DSD-440 with unresponsive formatter/control board

Both green LEDs are on. They're ALL on. This is a failure of the DC Power Up/Down circuit - See page 3-10 + 3-53/54 in June 83 Service Manual. If the components in this circuit (capacitor) are out of spec, then this may be the cause. Congrats on picking it up. I was tempted to bid

Re: Need help: DSD-440 with unresponsive formatter/control board

On Sep 20, 2016, at 12:49 PM, Julian Wolfe wrote: > > > > So the DSD-440 I got at VCF is completely unresponsive. All of the LEDs are > on and never go out, which is bizarre - they are supposed to go out in 1/10 > of a second after power on. > > > I tried disconnecting

Need help: DSD-440 with unresponsive formatter/control board

So the DSD-440 I got at VCF is completely unresponsive. All of the LEDs are on and never go out, which is bizarre - they are supposed to go out in 1/10 of a second after power on. I tried disconnecting everything but power to the card, and it still lights all LEDs. No jumpers that I