Vintage Synth Repair

Is there any particular component on the Juno 106 amplification/chorus
circuit that could cause one side to make a "tick" noise with every
LFO loop ? 

It may sound louder on one side compared to the other, if that helps...
Replaced the BBD's but no change. Thanks !

--- In vintagesynthrepair@yahoogroups.com, "gil_we" <gil_we@...> wrote:
>
> Is there any particular component on the Juno 106 amplification/chorus
> circuit that could cause one side to make a "tick" noise with every
> LFO loop ? 
> 
> It may sound louder on one side compared to the other, if that helps...
> Replaced the BBD's but no change. Thanks !
>

i think i have the same problem with my MKS-50....

i would be interested to know too....

--- In vintagesynthrepair@yahoogroups.com, "Dorus Manassis"
<thorosm@...> wrote:
>
> --- In vintagesynthrepair@yahoogroups.com, "gil_we" <gil_we@> wrote:
> >
> > Is there any particular component on the Juno 106 amplification/chorus
> > circuit that could cause one side to make a "tick" noise with every
> > LFO loop ? 
> > 
> > It may sound louder on one side compared to the other, if that
helps...
> > Replaced the BBD's but no change. Thanks !
> >
> 
> i think i have the same problem with my MKS-50....
> 
> i would be interested to know too....
>
Does that part of the circuit have a potentiometer?
Most discrete chorus circuits Ive seen have a pot that needs to find
the "sweet spot" where the oscillator works but doesnt overwork

Look for a leaky transistor in the chorus circuit. The general purpose NPN and PNP 
transistors that Roland used in so many machines seem to fail quite often. They begin to 
leak and cause pops. I come across them with leakage problems in TR909's all the time, in 
JP6 power supplies, and Juno 106's. They are 2SA115's and 2SC2603's. From memory 
these are used on the Juno chorus/output board as well.


--- In vintagesynthrepair@yahoogroups.com, "Scott" <painintheamp@...> wrote:

>
> --- In vintagesynthrepair@yahoogroups.com, "Dorus Manassis"
> <thorosm@> wrote:
> >
> > --- In vintagesynthrepair@yahoogroups.com, "gil_we" <gil_we@> wrote:
> > >
> > > Is there any particular component on the Juno 106 amplification/chorus
> > > circuit that could cause one side to make a "tick" noise with every
> > > LFO loop ? 
> > > 
> > > It may sound louder on one side compared to the other, if that
> helps...
> > > Replaced the BBD's but no change. Thanks !
> > >
> > 
> > i think i have the same problem with my MKS-50....
> > 
> > i would be interested to know too....
> >
> Does that part of the circuit have a potentiometer?
> Most discrete chorus circuits Ive seen have a pot that needs to find
> the "sweet spot" where the oscillator works but doesnt overwork
>

Well said. That was indeed one of these transistors !

Any known substitutes for these ?



--- In vintagesynthrepair@yahoogroups.com, "thirteentech"
<thirteentech@...> wrote:
>
> Look for a leaky transistor in the chorus circuit. The general
purpose NPN and PNP 
> transistors that Roland used in so many machines seem to fail quite
often. They begin to 
> leak and cause pops. I come across them with leakage problems in
TR909's all the time, in 
> JP6 power supplies, and Juno 106's. They are 2SA115's and 2SC2603's.
From memory 
> these are used on the Juno chorus/output board as well.
> 
> 
> --- In vintagesynthrepair@yahoogroups.com, "Scott" <painintheamp@>
wrote:
> >
> > --- In vintagesynthrepair@yahoogroups.com, "Dorus Manassis"
> > <thorosm@> wrote:
> > >
> > > --- In vintagesynthrepair@yahoogroups.com, "gil_we" <gil_we@> wrote:
> > > >
> > > > Is there any particular component on the Juno 106
amplification/chorus
> > > > circuit that could cause one side to make a "tick" noise with
every

> > > > LFO loop ? 
> > > > 
> > > > It may sound louder on one side compared to the other, if that
> > helps...
> > > > Replaced the BBD's but no change. Thanks !
> > > >
> > > 
> > > i think i have the same problem with my MKS-50....
> > > 
> > > i would be interested to know too....
> > >
> > Does that part of the circuit have a potentiometer?
> > Most discrete chorus circuits Ive seen have a pot that needs to find
> > the "sweet spot" where the oscillator works but doesnt overwork
> >
>

They are still available, I buy them from Wes Components in Sydney, Roland Australia still 
have them or a close sub, or if you get really stuck there are probably a dozen subs if you 
look in a substitution book.

--- In vintagesynthrepair@yahoogroups.com, "gil_we" <gil_we@...> wrote:

>
> Well said. That was indeed one of these transistors !
> 
> Any known substitutes for these ?
> 
> 
> 
> --- In vintagesynthrepair@yahoogroups.com, "thirteentech"
> <thirteentech@> wrote:
> >
> > Look for a leaky transistor in the chorus circuit. The general
> purpose NPN and PNP 
> > transistors that Roland used in so many machines seem to fail quite
> often. They begin to 
> > leak and cause pops. I come across them with leakage problems in
> TR909's all the time, in 
> > JP6 power supplies, and Juno 106's. They are 2SA115's and 2SC2603's.
> From memory 
> > these are used on the Juno chorus/output board as well.
> > 
> > 
> > --- In vintagesynthrepair@yahoogroups.com, "Scott" <painintheamp@>
> wrote:
> > >
> > > --- In vintagesynthrepair@yahoogroups.com, "Dorus Manassis"
> > > <thorosm@> wrote:
> > > >
> > > > --- In vintagesynthrepair@yahoogroups.com, "gil_we" <gil_we@> wrote:
> > > > >
> > > > > Is there any particular component on the Juno 106
> amplification/chorus
> > > > > circuit that could cause one side to make a "tick" noise with
> every
> > > > > LFO loop ? 
> > > > > 
> > > > > It may sound louder on one side compared to the other, if that
> > > helps...
> > > > > Replaced the BBD's but no change. Thanks !
> > > > >
> > > > 
> > > > i think i have the same problem with my MKS-50....
> > > > 
> > > > i would be interested to know too....
> > > >
> > > Does that part of the circuit have a potentiometer?
> > > Most discrete chorus circuits Ive seen have a pot that needs to find
> > > the "sweet spot" where the oscillator works but doesnt overwork
> > >
> >
>