once working self assembled pedal now stops functioning

[mightyboy88]

Hi guys,

i have a general guitar gadgets orange squeeze compressor.

It used to work fine until i decided to modify one of the internal trimpots to an external one(mod not performed yet)

I drilled a hole in the metal casing and in the process the IC chip got dislodged dropped out.

I placed the IC chip back in the IC socket but in the wrong direction(i.e. the dot facing the wrong way) accidently.

The effect has true bypass but couldnt work, i reversed the chip direction and it has failed to work too.

I have been trying to identify the possible faults and have resoldered joints and checked for broken wires etc.

I suspect the wrongly placed IC chip could have caused damage to some of the parts in the circuit and i have replaced all the electrolytic caps to new ones. However the effect still does not work.

Is there a possibility that the transistors. IC chips and unpolarised capacitors may also have become damaged?

Please also do offer experiences or possible reasons for the failure of the pedal

Thanks alot

David

 

[PatheinRaindropMoe]

from the orange squeezer schematic in ggg, the op amp is a 4558 chip.

If you reverse the chip and the effect was powered up, the v+ and ground pin will be at wrong receiving end. Pin 8 which is supoosed to be v+ become ground and pin4 which is ground, received the power instead. The ic might be damaged.

Anyway, if its the ic chip that got screwed, you can get replacement from simlim tower. They have jrc 4558d chip there, made in malaysia one, $1 a piece(+/- a bit) if i remember correctly.

One way when dealing with ic chip, its good practice to download the specification sheet online and check thru the pins configuration.

 

[mightyboy88]

Hey path bro

real sorry for such a late response

Yup u are absolutely spot on.

I changed out the IC chip n the effect is working again. However, I believe the quality of the effect has slightly deproved due to my swapping of the stock capacitors. Those were panasonic film caps i think. N my replacement parts were cheap ones from sim lim. :C

You think that could have had an effect on the voicing of the pedal?

 

[dric]

Hey man, that's a great pedal there. Very nice to mod also. Why did you swap out the panasonic film caps?
Anyways you could try putting in metal boxed or new metal film caps, and maybe swapping out some of the electrolytic ones for tantalum ones. You'll be amazed by the improvement. Why don't you socket the IC, then you can experiment with other IC's too. A new RC4559, NE5532 or the TL072, i personally like the 5532 for the orange squeezer. Lastly, you can also try changing the diodes.

And finally to answer your question: Yes, swapping out the panasonic film caps for lower end ones will affect the tone of the pedal..

 

[PatheinRaindropMoe]

one way to play around with different caps/resistors/diode(in already made effect circuit), is to get those single row component socket also available from Sl tower. Wire it in place of the components, anytime wanna change parts, will be easier. Good for playing around with different value components to try out the sound without need for soldering the components.

Once satisfy with perhaps couple of different value components, can wire to toggle switch/selector switch(2 way, 3 way or 6 way switches etc) as well and have it be controlled externally.

 

[mightyboy88]

thanks alot

i swapped the caps coz i tot it was the caps tt got blown lol. I think maybe i should try tantutalum caps then hahahah.

The socket row idea sounds good. Sound have done tt, now the pcb looks really burnt with all my desoldering n resoldering haha

The pedal has a noticable hiss sound when engaged, is that normal? Its like the hiss sound u get from turning on a distortion pedal but it causes a lot of feedback when i use it with a distortion pedal