Hummin on both channels, not on main amp as goes when the links are removed, require any advice or a manual or both. Thankyou Stuart
Humming is usually caused by an open filter capacitor, and usually in or near the power supply. It would be one of the larger say 1/2 inch across & bigger & 100 uf & larger. most can be tested in curcut using a volt meter with capacitance or an older meter with an analog needle set to ohms. For an old meter test: With the unit unplugged...attach the meter leads to the cap leads- the reading should go up & slowly climb- this is the cap charging- now reverse the leads- the needle should drop below zero for a few seconds then start to climb & charge again. This is the cap backfeeding the meter then recharging. If it just goes up a little & stops, the cap will need to be removed & tested out of circut.
Thankyou for your info, as you said, 470Uf @ 16V wouldnt read on ESR in or out of circuit. Thankyou Stuart
Hya, thanks for the info, just so hard to get to PSU section, was wondering if there was a common faults, narrow it down a bit, I have a ESR meter, so best to pull board out and make a start. Its hard to test the unit without almost complete reassemble. Thakyou will get back. Stuart
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