Moog Music Forum

Yes I've done this but not feeding 5v to the VCA (actually using another 911) and indeed it does change the linear/exponential output of the 911/902 combo. I just wondered if there was a simpler way ...the 911 circuit looks pretty simple but alas I'm not electronically fluent to modify the circuit. ...

Yes, I meant to say that it's probably a case of possibly changing the slope from linear to exponential....if it could be done by altering or adding some components ?

I notice on Arturia's Modular V software , there's an option to adjust the slope of the combined VCA/911.... Would anyone know how to modify the 911 schematic to achieve this ? I'm thinking of the Attack phase more than anything .A small control placed on the panel would be ideal to adjust the slope...

Brilliant....many thanks Roger...that's just what I hoped to hear. I'm going ahead with the project.

I'm considering using two Power-One units to power cloned Moog modules . The 12v is no problem but for -6v I've been advised to use a Power One HC5v, modify it slightly , and swap the positive/negative out to deliver the -6v. But would I have problems regarding grounding? ie using two separate trans...

Is it possible or has anyone adapted a HCC5 to obtain -6 v output ?
I have a 12v power- one and would like similar on the -6 side.

Thanks ...I would like to stick to Moog but yes a crystal based unit is going to be more stable ..I have one in mind which runs on +5 supply
And it all depends if I get the mini Moog a440 working ...

I made this circuit up as a stand alone reference unit for my modular but I never got it working_ I didnt pursue the problem however but as there are very few A440 reference circuits out there
I thought I would have another go
Has anyone made this unit as a stand alone ? ,(and got it working )?

I think you are correct...load makes no difference...

I suspected these parts were 7909....I guess they are even though they are clearly marked 7906.

But I've ordered from Little Diode just now and I'll see if these are the real Mcoy

Thanks ..I got that site but cannot get passed checkout..

I've been told the 7906 may need a load draw before they regulate properly ..I'll check this and re post.

But I found little diode can supply them on request

I've posted this on Muff Wiggkler but I'm looking for a supplier of 7906 TO-3 package
I got some off e bay marked as 7906(on top of regulator) but they output -9. to -10v no where near -6v
I cannot find any others in the UK

I'm struggling a bit with adding vibrato effect to my 921b oscillators . I used to take a low sine wave from a dot .com module and then route it thru a 995 attenuator into the frequency input of the 921a but I found that tuning became unstable with this method. With various degrees of vibrato the pi...

No info anywhere, no reply from COTK....

I know my COTK 921is designed for a +/-12 v supply ...
Can it be safely run on +/- 15 v ?

Thanks AM for taking the time to answer my query and supplying some good info and links. Well I think that's answered my problem or at least stopped me worrying about it. By the way your 950 project looks pretty good, I too was considering a keyboard project but not with midi features. In fact it wa...

Yes ..all my 911's work fine. ( I think !) What I'm trying to find out is does the 950 keyboard controller have any " pull up" voltage associated with the S trig output. I realise the S trig is simply two terminals shorted but would there be any difference by say shorting a 911 with a scre...