EM-5 intermittent switching

[pupina]

If this can help someone to help me, i post the schematic of Ibanez EM-5

http://www.experimentalistsanonymous.com/diy/Schematics/Delay%20Echo%20and%20Samplers/Ibanez%20EM5.png
.....I'm not able to insert the ling or the image...sorry

Thanks
Pupina

[Dirk_Hendrik]

Get the switch replaced. Common problem in soundtanks.

[pupina]

Getting the switch replaced is a big problem...that little switch is very hard to find!!
Anyway, i think that's not a mechanical problem, i think whit many probabilities it should be an electronics problem...i hope to be wrong
What do you think?
are you sure 100% about the switch!?
Anyway thanks for your answere
Carlo

[Dirk_Hendrik]

One can never be 100% sure. However, in all cases as described by you I found the switch beiing the faulty component due to poor contact as result of oxidation. Regarding that "Hard to find", I ordered a few at Farnell a few years ago. When intending to do that again 2 weeks ago they were unable to do so as they're not RoHS compliant. I see a problem arising there with RoHS and service parts....

[pupina]

received. thanks a lot

[pupina]

...i replaced the switch whit another take out from a NOS suntan pedal....nothing has changed!
i have to push many time to make the effect on....I'm sure now, it is an electric problem regarding this model of Soundtank, the EM-5
Maybe one of this days someone will help me find the way to fix this annoying trick
Thank to all the people in this forum

Pupina

[Dirk_Hendrik]

Wat's a suntan pedal ?

Cannot imagine "electric problem regarding this model of Soundtank, the EM-5" since the switching circuit as used has been usen in hundreds of pedals. The circuit does work. Onlt in your case there's a problem.
Could you tell me the voltage level on the intersection of R35, R36 and R37 without the switch pressed and with the switch pressed? When doing the 2nd don't try to turn the pedal on or off or whatever. Just close the switch and measure.

[pupina]

OK, I'll try this evening and I'll let you know.....now I'm working.
thanks in advance

Pupina

[pupina]

So...Dear Dirk,
the voltage level on the intersection of R35, R36 and R37 without the switch pressed is 2,38 V, then wen i close the switch i read in my multimeter 0,00, finally when i release the switch i read 2,38 again, but the led sometime turn on...other times remain off...
Pupina

[vortex]

The soundtank switches are pretty wimpy. This may not be the advice you need but it has worked for me. I've used Caig Deoxit on the soundtank switches and they have come back to life and worked well for a long time. Give the pedal a test before you assemble it up again to see if it isn't a mechanical issue with the housing.