freestompboxes.org

I friend of mine gave me a Morley SLDW for repair.
I found that the original schematic do not corresponds with the circuit,
it was therefore necessary to trace the circuit.
One more LED-LDR combination in real circuit and a somewhat different wiring identified.
The owner cannot rember if the pedal had been modified sometime in the past.
In the original schematic 7812 voltage regulator is shown, in the real circuit it is jumpered.
Likewise the power supply is 18 Volts DC in the schematic drawing, in the circuit it is 9 Volts DC,
but the resistors in seriell to the LEDs are the same as at 18 Volts.
The pedal do not works fine.
My impression is that the brightness of the LEDs are to faint.
Who knows more about the pedal?

Original Schematic: Traced Schematic: Shots:

I dropped the pedal for a long time, then I started the repair a few days ago.
Now, it is finished an works fine, with a DC-jack (pin negative).
The pedal works not fine using 9VDC power supply voltage, so I add a voltage doubler and the 12Volts voltage regualtor.
I choosed this TDA2003 voltage doubler to ensure a sufficient current. Here two another Vero-layouts with mounted ICs(Pentawatt H and Pentawatt V) Lochmaster 4.0 file:

Sorry typo.

The corresponding post has been deleted in the mean time by the board administrator.

Circuit update.
I made this modification for a friend.
He had the problem that in the background a low whistling could be heard over the amplifier.
I looked at the DC-voltage waveforms using the oscilloscope and found a rectangular ripple signal
with a base frequency of about 8 kHz with high frequency spikes coming from the voltage doubler with the TDA2003.
I installed a 2x47mH current compensated choke coil and a 470uF electrolytic after the voltage regulator in the manner shown in the schematic.
The DC voltages are now very clean with no ripple and the pedal works well now. .