Above the transformer in the schematic, there is a 12 Volts regulator

Do you mean this? I'm sorry but I don't understand where the 12V comes out. Perhaps the OUT output of the rightmost transistor.

 

Forget about the 12V regulator for now.
You need to get +15V at C1 and -15V at C2 with respect tp GND (common).

If not, remove the power adapter and measure forward and reverse resistance at CR1 and CR2.
Or measure AC voltage out of the adapter.

 

I have this at home, will it fit?

Not really. You are going to need something stronger with solvents and lube.

Happy to see the 8038 on the schematic (the box labeled FUNCTION GENERATOR)

 

@Dodgydave
The only pattern I have found online is the one on this forum:
View attachment 302634

The integrated circuits are these:
View attachment 302635

It's the 8038 chip, I would check the supply first and then the chip outputs, as others have stated..

 

Forget about the 12V regulator for now.
You need to get +15V at C1 and -15V at C2 with respect tp GND (common).

If not, remove the power adapter and measure forward and reverse resistance at CR1 and CR2.
Or measure AC voltage out of the adapter.

View attachment 302648

I don't get +15V or -15V .. I get 0.22V and 0.13V from the two capacitors
With the circuit unpowered, I set the multimeter to 200k ohms: C1 has impedance 61k and C2 infinite (remains symbol "1" i.e. out of scale on multimeter even with 2000k on multimeter)

 

Hello,

What is the AC voltage from the powersupply of the unit?

Bertus

 

Hello,

What is the AC voltage from the powersupply of the unit?

Bertus

I measure 33V AC at the pcb terminals:

 

Ok so follow the AC supply to the switch and then to the diodes Cr1/2, and the capacitors.

 

Hello,

That is strange. The shown adapter says 12 Volts DC and is from OKI.
It looks not the origenal adapter.


Bertus

 

I measure 33V AC at the pcb terminals:

The schematic calls for 12VAC. C1 and C2 would have been marginal with 12VAC and may have been damaged by applying 33VAC. The adaptor says it's 12VDC 1A and the schematic calls for 12VAC /300mA.

 

MG Chemicals 401B Nu-Trol Control Cleaner

I can't find it on Amazon and on Mouser it is only available with U.S. shipping. I live in Italy. Any other options/products?
Thanks

 

You are using the wrong AC adapter.

 

Hello,

That is strange. The shown adapter says 12 Volts DC and is from OKI.
It looks not the origenal adapter.


Bertus

Wait! I forgot to write this in the initial post!
The generator and its power supply were given to me by an old colleague, he does not remember whether the power supply is original or not because he has not used this generator for decades.
I thought about it now seeing your reply, sorry to have wasted your time.
If I can't find the original one, do you know what specifications a replacement non-original power supply should have? (in case I want to buy it)

 

Hello,

A simple transformer with an output of 12 Volts 300 mA (or higher current) would do.

Bertus

 

Look for something like this. It must say
INPUT: 240V AC 50Hz
OUTPUT: 12V AC (minimum 300mA, higher is ok).
(Note that the + and - diagram is a mistake.)

Buona fortuna!

 

I can't find it on Amazon and on Mouser it is only available with U.S. shipping. I live in Italy. Any other options/products?
Thanks

Any good product specifically for contact cleaning should do. A good music shop or supplier should carry something. Amplifiers and pedals require a shot now and then. Avoid cleaners with acetone as any overspray can damage panels etc.

 

I sincerely hope that you can fix this device.
When I was a young EE student in the early 1970s, I would have wet dreams of someday owning a Sabtronics function generator.

 

Look for something like this. It must say
INPUT: 240V AC 50Hz
OUTPUT: 12V AC (minimum 300mA, higher is ok).
(Note that the + and - diagram is a mistake.)

Buona fortuna!


View attachment 302656

I think they have 230VAC over there, so 230V AC would do too.

 

(Note that the + and - diagram is a mistake.)

Could it be indicating L and N?

 

It came back to life after many years.
Now I want to play some more with this power supply, but anyway I take this opportunity to thank everyone who has given me support in this thread (I can't tag you all!)




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