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Messages - Jazz P Bass

I would ditch the idea.
The transformer will not do anything to affect or color the sound.
In fact, you may be causing issues with the module.
As far as I can see on the schematic, the +16 & -16 Vdc is used for the opamp. IC 1.
C2 & C6 smoothing capacitors may be considered suspect as well as the ic.
Your + & - 16 volt supplies are being pulled down.
Preamps and Effects / Re: Fender STC1 Chorus Pedal
April 23, 2021, 11:22:41 AM
Awesome 'gift'.
Thank you sir.
Preamps and Effects / Re: Fender STC1 Chorus Pedal
April 22, 2021, 09:50:40 AM
I had to make a pdf of this.:)
Preamps and Effects / Re: Fender STC1 Chorus Pedal
April 22, 2021, 12:54:23 AM
Nice run down on the BBD circuit, Mandu.
The amplifier had a failure.
Take it to a tech.
Attached schematic.
When I listened to the mpg file my first thought was "that's a bad speaker".
But then I saw that you verified them as good.
Glad that you got it sorted out.
The dc voltages don't look bad at all.
You don't have access to a scope do you?
Next step is to measure the output transistor voltages.
The first stage opamp (pin #1 & #7), the driver bases & the output transistor bases. (the left leg of the component)
No signal. Volts dc.
Schematics and Layouts / Re: Gallien Krueger 100 MPL
March 10, 2021, 12:32:28 AM
That is one heck of of a circuit description write up!!!
You have not noted what is wrong with the unit but a good tech should be able to narrow it down with that excellent info.
Where are you located ?
Are you wiring it for Domestic (110Vsc) or Export (220Vac)?

Here is the 'Domestic' layout.

Blk (CP8)and Wht (PS4) are the Primary leads from the Mains plug.
I can only surmise that the Wht wire (PS4) indicates Power Switch tab 4.

Red -Ylw- Red:  is the 45 Vac taps with Ylw being the Center Tap
Blu- Brwn- Blu is the low voltage Vac tap with Brwn being the Center Tap.

The tabs on the PCB should be clearly marked.
Please check the power supply voltages for stability, sameness & lack of ripple.
+ & - 42Vdc
+ & - 16Vdc
This may be the correct schematic:
Well you do have a working amp to compare voltage readings to.
First off, is R 165 cement resistor still good?