I just finished building an amplifier with a preamp inside. Im splitting the AC input into the amplifier (directly) and the preamp + input selector, through an AC/DC converter.ñ, the input selector has a buck converter to go down to 5v (from 24v) Everything with star ground at main.
What I find weird is that if I touch with the black line the + of the preamp (24v) and the + of the input selector (5v), it shows continuity. The same if I touch every other point (except for the AC wired). Is this expected?
What I find weird is that if I touch with the black line the + of the preamp (24v) and the + of the input selector (5v), it shows continuity. The same if I touch every other point (except for the AC wired). Is this expected?
> it shows continuity.
"Continuity" is for trailer lights. Does it mean 1 Ohms? 10 Ohms? 100 Ohms? 1000Ohms?
We are Electronics Experts. We measure OHMS. Hundreds or thousands of Ohms is not unexpected across power supplies.
"Continuity" is for trailer lights. Does it mean 1 Ohms? 10 Ohms? 100 Ohms? 1000Ohms?
We are Electronics Experts. We measure OHMS. Hundreds or thousands of Ohms is not unexpected across power supplies.
What constitutes continuity varies among the different multimeters. Some multimeters will indicate continuity only if the ohmic value is less then 25 while other meters will still show continuity with ohmic values at 300 ohms or more. Thus the call for specific numeric values.
Please forgive me for stating what's probably obvious, but resistance/continuity checks are meaningless if the unit is powered--- so make sure power is removed and all caps have had time to discharge. An interesting experiment would be to swap multimeter leads (i.e. opposite polarity). You may see a different result. Resistance measurements should be more insightful.
Cheers!
Cheers!
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To boot I suspect jtmsrl is measuring "continuity" with the preamp and power amp >>ON<<
In that case, any voltage difference between 2 points will make the multimeter BEEP! which of course means nothing and to boot may very well BURN the meter.
Dear jtmsrl, is there any real problem you want to solve?
In that case, any voltage difference between 2 points will make the multimeter BEEP! which of course means nothing and to boot may very well BURN the meter.
Dear jtmsrl, is there any real problem you want to solve?
the input selector has a buck converter to go down to 5v (from 24v) Everything with star ground at main.
What I find weird is that if I touch with the black line the + of the preamp (24v) and the + of the input selector (5v), it shows continuity. The same if I touch every other point (except for the AC wired). Is this expected?
Probably just the filter caps holding charge - multimeters don't inject large currents so it will take ages to reach DC steady state this way.
Use the resistance range and you should see the value constantly changing as the caps charge.
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