Stickman393
Well-known member
I'm losing my mind here.
I followed my input signal here to the BBD, at which point...none shall pass. I didn't think much of it, as I suspected my clock driver was counterfeit, so I ordered a new clock driver and spent the next few days explicitly ignoring the problem and hoping a more reliably sourced clock driver would fix it.
Yeah...after 35 years you'd think I woulda learned. But I pride myself on steadfastly refusing to learn simple lessons. Cause if you don't stand for something you'll fall on everything. Yes, EVERYTHING.
But this is where the plot thickens and I'm...just...huh?
I'm using a 3007 & 3101 combo, with pads 2 and 3 shorted on SW 1 & 2 via the solder pads, which matches the PCB markings as well as the datasheet for the 3007.
But there's a little weirdness happening with R27. Pin 5 of my socket connects to ground, pin 1 to +9vdc. Makes sense, the chip is supposed to operate around -15vdc.
BUT...the far side of R27 (Away from the BBD) is common with pin 5. Huh?
A visual inspection confirms this: the far pad on R27 is part of the ground plane (confirmed both by measuring resistance and by observing that telltale "+" around the pad). The end closest to the BBD leads to a trace on the bottom of the board that connects to pins 7+8 on the BBD.
Basically, via continuity tests, I'm seeing the attached. It would work just fine with a 3207, but my 3007s aren't passing any signal in this state.
I can simply pull R27 up from the ground plane tab & run a jumper to +9V, which seems like the simplest solution here. Does anybody else here have this same board & can get eyes on theirs to confirm?
I followed my input signal here to the BBD, at which point...none shall pass. I didn't think much of it, as I suspected my clock driver was counterfeit, so I ordered a new clock driver and spent the next few days explicitly ignoring the problem and hoping a more reliably sourced clock driver would fix it.
Yeah...after 35 years you'd think I woulda learned. But I pride myself on steadfastly refusing to learn simple lessons. Cause if you don't stand for something you'll fall on everything. Yes, EVERYTHING.
But this is where the plot thickens and I'm...just...huh?
I'm using a 3007 & 3101 combo, with pads 2 and 3 shorted on SW 1 & 2 via the solder pads, which matches the PCB markings as well as the datasheet for the 3007.
But there's a little weirdness happening with R27. Pin 5 of my socket connects to ground, pin 1 to +9vdc. Makes sense, the chip is supposed to operate around -15vdc.
BUT...the far side of R27 (Away from the BBD) is common with pin 5. Huh?
A visual inspection confirms this: the far pad on R27 is part of the ground plane (confirmed both by measuring resistance and by observing that telltale "+" around the pad). The end closest to the BBD leads to a trace on the bottom of the board that connects to pins 7+8 on the BBD.
Basically, via continuity tests, I'm seeing the attached. It would work just fine with a 3207, but my 3007s aren't passing any signal in this state.
I can simply pull R27 up from the ground plane tab & run a jumper to +9V, which seems like the simplest solution here. Does anybody else here have this same board & can get eyes on theirs to confirm?
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