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TS 808 mod problem or not?


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8/24/1999 2:46 PM
nic TS 808 mod problem or not?
I changed the opamp to a regular RC4558, which sounded okay. Most importantly I put a socket in there for future mods... The problem I have now is there seems to be a bit of distortion coming through when in bypass mod. Does this have anything to do with the two resistors that were changed on the output jack? I don't think I am imagining it can't hear the distortion when the pedal is out of the loop.  
 
 
 
 
 
thanks,  
 
nic
 
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8/24/1999 3:24 PM
R.G.

Leakage of distortion in "bypass" is usually a problem with the switch fets or their gate drive - assuming that there wasn't a problem with the soldering or parts when you made the mods.  
 
 
 
As a general principle, always suspect what you did last as possibly being a problem if you find a new bug after changes.  
 
 
 
I would carefully inspect for solder bridges, shorts, overheated components, etc., and then look at the gate drive to the switch fets, possibly replacing them.
 
8/24/1999 7:45 PM
nic
in removing the op amp I might have over heated somethings. I didn't use the clip lead method to removed the chip. I used the lazy ass sloppy method which consists of pushing the leads out with the soldering iron... Would the heat be enough to transfer along the buses? Are the other components that sensitive? Man, The leakage isn't a lot but I think it'll bug me!  
 
 
 
nic  
 
 
8/24/1999 7:56 PM
R.G.

It's possible to get heat damage that way, certainly. You might also have a micro-blob of solder that fell into something else.
 
8/24/1999 8:04 PM
nic
the last thing I did was change the resistors. I suspected them first would you suspect them? Really, I spent much less time removing those. When I get home I check more.
 
8/24/1999 9:00 PM
spyder
nic, when it comes to soldering, the bigger the glob the better the job
 
8/24/1999 10:42 PM
nic
RG where whould I get those FET's if I find they need replaced? Do you have some that would be ready-to-go? How should I find out if there is something wrong with the ones in there now?
 

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