so i have a very low level noise from the speakers and an odd cenario
The amp trips the breaker if i depress the EQ defeat switch
The amp trips the breaker if i depress the EQ defeat switch
Ok, you may have a leaky coupling capacitor, or a bad switch.
Don't ever push that switch until it's fixed.
Don't ever push that switch until it's fixed.
It could also be an ultrasonic oscillation somewhere before the tone control, although rayma's leaky coupling capacitor sounds more likely.
Probably a silly question but do you mean an overcurrent breaker or an earth leakage breaker?
I'm assuming it doesn't trip when the speakers are not connected.
So not load current related by the sound of it. I'd have to look at the circuit and have a think on that one.
If the amp turns on OK with the EQ switch already pressed in then I would next see it it is all basically functional in that state. In other words DC offset correct and that it sounds 'normal'. Just don't operate the switch with speakers connected.
If you are measuring that at the speaker terminals then it looks normal, the output is floating when the speakers are off and will be picking up loads of stray hum and noise.
If the amp turns on OK with the EQ switch already pressed in then I would next see it it is all basically functional in that state. In other words DC offset correct and that it sounds 'normal'. Just don't operate the switch with speakers connected.
If you are measuring that at the speaker terminals then it looks normal, the output is floating when the speakers are off and will be picking up loads of stray hum and noise.
Can you clarify exactly what trips?
Is this a user resettable trip on or in the amp itself (like a button) or do you mean something else like a trip external to the amp (in the home like a leakage breaker).
If it is in the amp can you locate it on the circuit diagram so we can see exactly what this trip is.
Is this a user resettable trip on or in the amp itself (like a button) or do you mean something else like a trip external to the amp (in the home like a leakage breaker).
If it is in the amp can you locate it on the circuit diagram so we can see exactly what this trip is.
It's the internal breaker on the pcb and it automatically resets when you let the switch back out again
I'm struggling to piece it together.
Can you identify the breaker on the circuit diagram?
I can't grasp what this breaker is at this point.
Can you identify the breaker on the circuit diagram?
So not normally user accessible if its internal.
Let what switch back out again?
I can't grasp what this breaker is at this point.
That looks like the speaker relay and it will be being tripped by a sudden shift in the DC voltage at the amp output.
You will need to look at the EQ circuitry (identify the EQ switch on the circuit) and see what the EQ switch actually does. There should be no change in DC conditions when the switch is operated. It sounds like the power amp input/s are seeing a sudden step change in DC voltage and that is triggering the DC offset protection.
You will need to look at the EQ circuitry (identify the EQ switch on the circuit) and see what the EQ switch actually does. There should be no change in DC conditions when the switch is operated. It sounds like the power amp input/s are seeing a sudden step change in DC voltage and that is triggering the DC offset protection.
Ok i will have a look later
Ive not really got into this one yet as i was waiting to get my hands on a good quality copy of the circuit diagram, which i now have, but is too large to post on here 👍
Ive not really got into this one yet as i was waiting to get my hands on a good quality copy of the circuit diagram, which i now have, but is too large to post on here 👍