Hello!
I am trying to repair an Ibanez SD9 with a switching problem. I have built A LOT of pedals but I have never messed with FET switching. I'm attaching a schematic of the pedal. I replaced the switch thinking that was the problem and it was not. The pedal will switch if I touch the red/white wire to ground but I have to hold it on there for a second or two before it happens. Is it possible that a FET is just reacting too slow and needs to be replaced? The momentary switch is of course a really quick connect/disconnect so it's not doing the trick. If I desolder the red/white wire and touch it to the black wire on the other side of the switch for a second or two the pedal will switch on/off.
Ideas?
FET switching n00b here with a question.
- OC26
- Breadboard Brother
Does the LED switches on and off quickly or also slowly?
If it's also slow I think there is no problem with the FETs but with the flip-flop.
Have you inspected the components and tracks carefully? I found a similar erratic behaviour in a TS and the only problem was a shortcircuit between two components leads because they were bended...
If it's also slow I think there is no problem with the FETs but with the flip-flop.
Have you inspected the components and tracks carefully? I found a similar erratic behaviour in a TS and the only problem was a shortcircuit between two components leads because they were bended...
- bajaman
- Old Solderhand
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the flip flop is where the problem lies
First off - increase the value of the 1000pf capacitor at the bottom right of your circuit drawing - try 10n - 100n.
If that does not work, next, replace the two 1000pf capacitors above it.
If that does not work - replace the custom (CR1 and CR2) networks.
If that still has not fixed your switching problem, then replace the two flip flop transistors.
Hope this helps
Good Luck
bajaman
First off - increase the value of the 1000pf capacitor at the bottom right of your circuit drawing - try 10n - 100n.
If that does not work, next, replace the two 1000pf capacitors above it.
If that does not work - replace the custom (CR1 and CR2) networks.
If that still has not fixed your switching problem, then replace the two flip flop transistors.
Hope this helps
Good Luck
bajaman
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