Crest Audio CS18 Amplifier

[Andrewv1]

Hi Gents I'm in need of help. I got a CS18 in for repairs 220v is present at the mains switch and through to the front mounted PCB but does not turn on, This is a very compact amp so space is very limited to get in. Where should I start to look????😡😡 I Thank You in advance

Regards
Andrew.

 

[MAAC0]

Start with the basic checks. Are there blown Fuses / Thermal trip fuse on the rear sometimes / Thermal resistors on the heatsinks cutting transformer ? Do you get Rail voltages at the Bridge / Main capacitors. You say 220V is the on the front. Does the 220V gets thru the switch into the primary of the transformer ? Do you see discolored / Smelling / burnt components / Water damage ?

 

[Andrewv1]

Hi MAACO. I found the probelm. It was as you said, .... Thermal Resistor (Thermistor) leg broke off and that leads between the Neutral and relay to turn the Amp on. I will repair that first and then check the rest of the circuit before turning on the power amp side. Thanks for your advice which put me in the right direction. I did see that nothing smells burnt inside the amp, so I hoping all is OK.

Regards
Andrew.