All waves on, vcf fully open etc, at +5 will distort... The 10k resistance can be tweaked, such as 5k for a less pronounced curve. It can even be across the wiper and the other terminal of the pot for an anti log curve. R165 can be temporarily bypassed with a pot wired as rheostat to vary the resist...

Any news?? It´d be good to know if at least one worked

It´s intriguing because the positive supply is what tames down the control voltage, like take -10V, add +5V and the sum is -5V... Have you traced the entire control path? Another curious thing is the 10k law faking resistor for vr3 seems an afterthought, as it has no ref. number and there´s no sign ...

ha! where is r165??
Are you going to decrease the resistance of r165 from 15k to say 10k?

Ok. So, its actually only one slider. Sorry. Its vr3 lfo. Note the 10k resistor. Do the same for the vca level slider and that should fix it. Bye now.

Mooger5 wrote:
Voltage across pin7 of connector for VCA Level and ground:
-5 = +3.84V
0 = +2.74V
+5 = -6.13V

polysixer wrote:
Connector Pin 7

-5: 3,89mV
0: -0,78mV
+5: -6,18

Wait. Just to be clear, your readings there are in actual Volts, not miliVolts, right??

It's -0,7 too. I also doubted about the connector or cable and measure them with no fault. So it seems my signal is sent linear. Shouldn't the resistor network before VCA convert it to logarithmic after all? No. I was wrong. It´s only a common voltage divider, no law change at all. Your chorus boar...

This is how yours should respond: left to right is slider position -5 to +5, down/up is positive to negative output, or quieter to louder. https://d2vlcm61l7u1fs.cloudfront.net/media%2Ff7f%2Ff7f1fe35-eb42-4b3f-86e4-2456da90cf5c%2Fphp5uVnzV.png EDIT: the previous image was mildly confusing. This one´...

TR5 - emitter is indeed to -15 but collector goes into +15 through R46 and R50, so just wondering if a failure in this transistor explains the resistance drop of R165 in circuit. That could explain the scaling fault I guess. Furthermore, why does R17 connected to the same +15 line measure correctly...

IC5: pin 7 and pin 6 = +11.96V pin 5 and pin 6 = -2.7V Look for hairline solder bridges near pin 5 as some pads there are too close. Don´t use RoHS solder. Voltage across pin7 of connector for VCA Level and ground: -5 = +3.84V 0 = +2.74V +5 = -6.13V Voltage across C7 is around +1.2V at Zero. R165 in...

Forget it! I dug out my Juno from storage, and my readings don´t match yours! The extremes are identical, -5 = 90mV and +5 = -30mV, but at halfway it reads +75mV! It reads Zero volts only at +2.5. The readings are an aproximation because they lag due to that capacitor, but we can figure the control ...

Hi. Good observations. You should have included the voltages between R30 and the connector. But for now from your readings we can see the response seems linear. Zero at +30mV then +60/-60. We should remember that zero on the front panel doesn´t have to mean zero volts in the control circuitry. It´s ...

Thanks. TBH I can´t make much of it even in English. As you can see in the graphics (page 5) it says with a control voltage of -300mV the maximum gain is 50dB, and with a CV of +300mV the minimum gain is -50dB. So the more negative the CV goes the louder it gets. The response being linear, with zero...

I guess all that will remain is to isolate IC3 by connecting pin 3 to pin 1, then to pin 5, etc... a piece of wire will do.

You´re welcome. Congrats!