[sdiy] Jupiter-8 'selected' op-amp replacement

[Tony Kalomiris]

Hi,I've been working on this JP-8 and several oscillators are 
unsteady (vibrato like effect) and
when I scoped around the VCO the problem seems to be pointing to the 
TL080CP as the culprit.

My question is how do I go about matching these - a pair is needed in 
each current controlled oscillator- without any special test rig ?

I'm also concerned about the thermistors epoxied onto the CA3046, 
what if I have to change those as well,: how do I remove them without 
damaging them , they look very fragile (BTW where can I buy 
replacements just in case I need them ?)

Sorry for all the questions it's been a while since I've worked on 
one of these beasts and I'm a little gun shy.

Thanks for the help with the Strobe tuner as well I ended up using 
the Lissajous technique suggested in the service notes
it's more fun to watch the funky patterns than a spinning disc ;)

Oh isn't concert A 440 Hz? Why does the manual suggest 442 hz,884hz etc ?

Tony K

P.S. I still have the EMS circuit cards if anyone is still interested 
on this list.I've received alot of inquiries but no takers yet. 


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