Wednesday, 9 March 2022

 

I can now supply panels for the standard 8HP "Moog" modules: 901A, 901B, 901C, and 992 (see the "Moog Eurorack Modules" page).

These are high quality 2mm anodised aluminium in black with silver graphics (including the side "strip" to match Behringer System 55 modules).

Panels are made-to-order, the lead time for production is normally 2 weeks.



 

If you require white graphics instead of silver, I can supply you with the FPD files, and you can then order yourself directly from Schaefer AG or similar companies.

 

Tuesday, 8 March 2022

 Panels have been delivered for my 901A, B and C (and also for my forthcoming 904C filter coupler):

 


 

Sunday, 27 February 2022

I've just completed building the (originally rare) Moog 901C output stage. 
 
This amplifies standard Moog waveform levels for use as a deep modulation source, also generating positive-going and negative-going pulse waveforms. It has two complementary outputs.
 
As the original required a 3-pole 6-way switch, I've added electronic switching of the output waveforms, otherwise it's the original Moog circuit.
 
On the initial PCB run, the slots for the jack socket pins are not correctly cut, so I'm offering them at a reduced price (or free with 901A and 901B PCBs). The build document shows how to modify the PCB.
 
Works with my 901B oscillators, or with Behringer System 55 oscillator modules. 

 
A trial panel is on order.

Friday, 25 February 2022

 901B Oscillator PCBs are back in stock.

The latest PCB version has some minor changes:

- C100 (470uF) changes from axial to radial, as radial capacitors are more easily sourced.

- new option to use a 3 pin "turned pin" socket (half of a 6 pin socket) for the "selected" transistors T7 and T10.

The build document has been updated (V1-1).

Sunday, 6 February 2022

 Two videos of my 901A Oscillator Controller with 901B Oscillators, with temporary panel. 

 

General overview (the scaling of the 901A is not optimum in this):


 


901A scaling following adjustment:


 


 

 

 


Friday, 28 January 2022

 Available shortly: DIY (do-it-yourself, build-it-yourself) "Moog" modules in Eurorack format to complement the Behringer "System 55 " modules:

- 901A Oscillator Controller

- 901B Oscillator

-- 992 "Control Voltages" (Control source switching and adder)

- CP3/CP3A Mixer - can be used with the "992" PCB to make console panels, or on its own.

- "Universal daughter board" PCB - to facilitate easy connections to the back of Behringer modules.






Under development:

901C Output Stage

-  904C Filter Coupler

-  901 Oscillator



 

 

 

 

 


Tuesday, 14 December 2021


 

 My prototype Moog 901B in 8hp of eurorack. 2 PCBs, all thro' hole. The rear PCB holds the oscillator, the front PCB holds the sockets, pitch control, range switch and range caps (plus an op-amp as I've added a PWM input).Two Molex connectors on the rear are for the "bus" from the 901A controller, plus one with all of the outputs on it.

The extra pot and wiring in the pictures is because there is (as yet) no 901A controller - the design for the 901A is ready, but no point in proceeding with it until I had a working oscillator!

P1080934.JPG
P1080935.JPG
P1080936.JPG
The output:
 

(any glitches visible on the triangle and sine are because I don't yet have all of the range caps installed - these are also used for filtering the triangle waveform).

While the prototype uses thonkiconn jacks, I'm swapping it (and the 901A) to use PJ3410's, as the Alpha rotary switch sits higher on the PCB than I had originally envisaged. I could also do with using a longer shaft pot for the pitch control.