[sdiy] asm1 lfo and power supply

[René Schmitz]

At 17:25 10.11.01 -0500, Rob B wrote:
>> To be honest I'm still working with a very bad powersupply built around a
>> 7815 and 7915. Worse is, that I have -17V instead of -15 (don't ask me
>why -
>> only the 7915 knows...).
>
>Check the grounding of the 7815/7915.. If the ground is bad, there might be
>a reference induced by weak grounding/resistive grounding, which is then
>added to your regulated voltage. So, if your ground is weak, then perhaps
>add a few jumpers to ground it better and see what happens.

Also possible the regulator isn't seeing its minimal load. (Or maybe at least 
wasn't when you measured that.) Some regulators depend on that for proper
voltage regulation. A 1k resistor across the output terminals is usually
sufficient while testing. I've also seen these oscillating when no load is
connected.

Cheers,
 René



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uzs159 at uni-bonn.de
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