No SS voicing

[Tweeddeluxe1]

Update: I checked the signal on a working mp1 with my scope set up and I definitely see signal in places I don't in my troubled mp1 with no SS voicing. In fact I have noted in comparison to the "good mp1", I don't have signal on u7, u8,u6 or u2 and only pin 3 on u13. I noted signal on diodes d14 and d15 in the working mp1 and not in the one in question.

[MarshallJMP]

Ok let's start with U4 pin 1 what do you have there? what's the OD1 setting?
The input signal is that 600mV rms or 600mV peak to peak?

[Tweeddeluxe1]

Ok let's start with U4 pin 1 what do you have there? what's the OD1 setting?
The input signal is that 600mV rms or 600mV peak to peak?

I have a sine wave on scope on pin 1 and pin5,6,7 also. I'm totally new to the scope and generator. My freq is 1k and and generator set at 0.600v ampl . Hope this helps . Just bought some cheap Amazon equipment to start learning. The od1 setting is at 5, with preset 9 on SS voicing.

[MarshallJMP]

What equipment did you buy so I can have a look what you have?

[Tweeddeluxe1]

SeeSii dds signal generator jds6600-15m

Vevor sds1102 oscilloscope.

I tried to send pics of the two but the file might be too large.

[MarshallJMP]

Looks decent for what you need. I'll have a look at it tomorrow, it's past midnight over here.

[Tweeddeluxe1]

Your help is greatly appreciated.

[MarshallJMP]

Ok looks like it's in Vpp so setting is ok. So what do you get on pin 1 U4? Does the OD1 setting change the amplitude of the sine wave?

[Tweeddeluxe1]

Ok looks like it's in Vpp so setting is ok. So what do you get on pin 1 U4? Does the OD1 setting change the amplitude of the sine wave?

Yes.increasing od1 gain while probing u4 pin 1 does increase the amplitude of the sine wave.

[MarshallJMP]

OK you should see that signal on R59 at 70% of the amplitude on pin1 u4

[Tweeddeluxe1]

OK you should see that signal on R59 at 70% of the amplitude on pin1 u4

I'm seeing no signal at r59

[MarshallJMP]

Ok take an ohm meter and measure between U4 p1 and R59, should get 2k or less.

[Tweeddeluxe1]

Ok take an ohm meter and measure between U4 p1 and R59, should get 2k or less.

I'm getting 256k from u4 pin 1 to r59(measured on side closest to u4).  This measurement was taken with power off, should I take with power and signal passing?

[MarshallJMP]

And the other side?

[Tweeddeluxe1]

And the other side?
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Approximately 710k