Repair of an old Ibanez UE 3030B multieffect.
Fixed an annoying 100Hz hum.
Ibanez UE303B service
Repair of a Protein dual overdrive
A dual overdrive that turned in to a single one.
Symtom, green led lights up but passes no sound.
Surface mounted circuit board.
Browne Amplification Protein guts
All voltage readings came out fine. Traced the signal loss at the joint between C12 and R16 and resold the joint at C12. So we got ourself a dual overdrive again.
/Krister
MXR Micro Amp
Got a MXR micro amp in for service and modification.
The fried original TL061 opamp is now replaced with an OPA134 and the old tantalum capacitors was replaced. Rewired the bypass with a new 3PDT switch for true bypass. Mounted a 2,1mm negative center DC jack.
View of the DC jack.
/Krister
Colorsound Frankenflanger repair
About the Colorsound Flanger in an earlier post here. Found some schematics that helped rebuild the circuit.
Gut shot of the pedal in a working state.
So pleased to here it producing flanging sound again. Here’s a short soundclip.
/Krister
Boss DD-3 repair.
Here’s another Boss DD-3. The pedal gives signal in bypass, with effect engaged there’s just dry sound.
Someone has done some repair to the circuitboards power section seen in the upper left on this image.
The Mode selector rotary switch out of the chassie for replacement.
Old vs new rotary switch.
So what’s wrong with it. Found that C34 was broken, it did not pass any signal to the expander circuit. Had it replaced and got the delayed signal through the circuit, though at to high level and distorted. C31 was the cause of that problem. With C31 replaced the pedal works as it should. The tantalum capacitors C32 and C33 was also swapped with new ones as they do tend to fail in time. Checked and adjusted the high and low end of the Master clock frequency.
Here’s the service notes: Boss DD2-DD3.
/Krister
Nadine’s Distortion
A rare piece of non functional equipment, a Nadine’s Distortion on the workbench.
Gut shot, the circuit board in nice condition.
Component side.
The 6552 opamp was burnt, once replaced the pedal’s rocking again. Image of the circuit board with a socketed RC4558 as replacement for the 6552, the old electrolytic capacitors changed and a new battery clip installed.
/Krister
Tube radio repair
An old Luxor 1950:s tube radio.
/Krister
Yamaha CH-01 Chorus repair
A chorus from the -80:s, the Yamaha CH-01. Based on the MN3009 256 stage BBD chip and the MN3101 clock generator.
Had the circuit recaped and trimmers adjusted for bias, clock speed and depth.
And here we have a chorus once again delivering.
/Krister
Spare parts
Received a shipment with parts for a Marshall 2205. Thumbs up for Tube-Town, they sent chocalate with the package!
/Krister
Malfunctional Zachry D250 mono block
Here’s a Zachry D250 solid state amplifier. It stopped working producing only a 100Hz noise. Look at them blue filter caps, seems a bit swollen.
Here’s a picture from the bottom of the caps.
Those caps are out of date. Had a hard time finding 15000uF 63V caps with a diameter of 35mm. Finaly found and ordered F&T :s with the right values but a diameter of 40mm. I should be able to fit hem.
/Krister