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MattN's Achievements


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  1. Just to confirm that I would like what is listed against my name in the table. Thanks!
  2. Sure, I’d like 2x GRHVxxx 1x GRLV79xx 1x GRLV78xx 1x Main Board 1x miniT2 Thanks!
  3. Could you add me to the list? I'd like one set for a mini T2. Thanks!
  4. Adding a 100k resistor worked. The problem seemed to be only with one channel but caused the effect in both when they were connected to the same power supply (!?). Latching was to B+ on both outputs, permanently, immediately after the high voltage was applied. I use a cpc1117N as a delay retrofitted to the GRHV boards that didn't have it built in, so the tubes are pre-heated. I've attached a picture below. I'll test more thoroughly but probably not till the end of the week. Happy to *try* to answer any questions: though I've built quite a few different KG amps and can follow instructions, I wouldn't say that I *understand* anything.
  5. Yes. The one connected to the trimmer.
  6. I've built the Carbon-Triode with the new servo using Kevin's boards. The board works, as does the servo, but it sometimes latches to B+ at startup. Is there an obvious cause of that I should check for? It doesn't happen when the servos are disconnected, and one channel seems more susceptible than the other. I had to change the tail resistor to 200R to get the offset to zero.
  7. The second version of both boards has the servo from Kerry's schematic. There's no obvious way (to me anyway) to disable it. With the servo components removed the offset pot works and I can adjust the offset and balance to a volt or two from zero. I guess that means the servo works.
  8. I built this yesterday. There's some noise that I need to track down, but otherwise it seems to work. The offset adjusts to within a few volts using the balance pot; the offset pot doesn't seem to do much. Offset drifts a bit and I'm not sure I'm adjusting it right. Is there some way to disable the servo?
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