Does that mean that you didn't measure the voltage or that you measured it and there was no voltage (=0v)?
2385 reconnect PS00 to P400 pin question
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Sorry i connected red probe on13. Black probe on 14, set meter to dc voltage turned on receiver, after click read 80.7 vdc
With the voltage being to high, would that stop the signal for sound , protection of the receiver kicking in, .. or is that power nothing to do with signal ? Maybe the new relay is working too well and not allowing right or left speaker signal, or am i way off base.
The coil voltage has nothing to do with the "signal", only whether the relay is ON or OFF. 0V across the coil should be OFF and 48V should be ON.
I am puzzled about the 80V although the circuit shows a -77V on the transistor which to mee does not make sense unless resistor RN05 1.5k/1W resistor drops half of the voltage. Maybe with AC unplugged, measure the resistance of RN05 connected to the relay.
RN05 = 1.199 K it looks like its red red red which would be 1.2k...Im not sure why my new relay does not work if it closes when powered?
RED RED RED = 2.2k Ohms, not 1.2k. 1.2k would be BRN RED RED.
You measured 1.199k in circuit.
The schematic shows 1.5k so it's probably OK.
It may measure low because it is in circuit.
Here is the math.
Relay coil resistance Rc = 2725 Ohms (from datasheet)
RN05 series resistance R = 1.2k Ohms
Total R = 2725relay + 1200RN05 = 3925 Ohms
Vtotal = 77V across relay coil + VRN05
Calculate current through relay:
I = V/R = 77V / 3925 Ohms = 0.02A through resistor and relay coil
Voltage drop across VRN05 = I * R = 0.02A * 1200 Ohms = 24V
Voltage drop across relay coil should be Vrelay= (Vtotal - VRN05) = 77v - 24v = 53v. (which is close to the 48V relay spec)
But somehow you are measuring 80V! 
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A relay typically could fail in one of two ways:
- A failure in generating the coil voltage (48V) or in the relay coil itself would cause the relay to be stuck in the OFF state.
- A failure of the contacts, typically a burned or corroded contact, could be due to age or too much current. It could be either or both contacts, and could affect only one channel.
This may be my mistake, i measured voltage without relay, i will connect to relay then measure 13 to 14 and get back.RED RED RED = 2.2k Ohms, not 1.2k. 1.2k would be BRN RED RED.
You measured 1.199k in circuit.
The schematic shows 1.5k so it's probably OK.
It may measure low because it is in circuit.
Here is the math.
Relay coil resistance Rc = 2725 Ohms (from datasheet)RN05 series resistance R = 1.2k OhmsTotal R = 2725relay + 1200RN05 = 3925 OhmsVtotal = 77V across relay coil + VRN05Calculate current through relay:I = V/R = 77V / 3925 Ohms = 0.02A through resistor and relay coilVoltage drop across VRN05 = I * R = 0.02A * 1200 Ohms = 24VVoltage drop across relay coil should be Vrelay= (Vtotal - VRN05) = 77v - 24v = 53vBut somehow you are measuring 80V!
Yes , i ordered exactly that part number, wont make that mistake again. Also will be looking at all resistors and transistors on that board just in case there is an issue
I installed the new relay, do to having to enlarge the holes i added wire jumpers to traces to make sure contact was complete. The new relay works but still no right channel, i hear a little sound when volume is as low as it can go but not sure it it isnt the left bleeding over. Maybe should have followed both channels in case at some point we followed the wrong channel. I dont understand why before i started when wiggling the volume pot , right would come on for a few seconds, now nothing, I tried touching all of the boards with a pencil, rubber end to see if it was a bad solder or crack, no sound, tried freeze spray, no sound.
Instek GOS-620
Yes thats it. I have a signal generator but it came not working, may just be connection, i will open it up and clean all contacts and see if it will work. not sure how i will know its working but i will figure it out, if not i will borrow one.