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AM1040 - 16 step Analog Sequencer
Introduction
In the 1975 Polyfusion introduced a basic 16 step analog sequencer. It appeared in both a modular format (2040) and as a stand alone box (AS). This simple but effective design was based on CMOS technology. It can be easily cloned. It is hardly an original idea or design, but it's a quick way of getting a basic and expandable 16 step sequencer. In 1980 the 2040 cost 475 US Dollars.
Original Circuit
The Polyfusion 2040 Analog Sequencer has one bank of 16 control voltage steps. It can be expanded to many more banks, each with 16 steps, using the Dual Row 2042 module. There is an internal clock with variable Rate and voltage control. An external clock can be used and the sequences can be manually stepped. Each step can be skipped, or stopped at. 16 LED's show the sequence position. There is a single control voltage output which is not quantised, and there are Gate and S-trigger outputs.
Original Specifications:
- Tempo: variable from 0.14Hz to 33Hz
- Gate Time: variable from 10 - 90%
- Portamento: variable from 0 - 10 seconds
- CV Outs: 0.3 to 3V or 10V
- A LED for each of the eight steps
- Trigger In and Gate Out
- End Pulse Out
- Tempo CV In
- CV1 and CV2 Out
AM Circuit The Analog Metropolis Model 1040 replicates the Polyfusion circuit
exactly. It is built on 2 new PCB's that mount to a standard 4U 135mm wide Analog Metropolis panel. The only tricky parts to find are the temperature compensated resistor (SDT1000) - which Roland still have in stock, and the dual
transistor (2SA798) - which some electronic stores still have.
Features include:
- Minature slide switches
- Minature pots, Spectrol 248 with 3.18mm shafts
- Minature rotary switch with 3.18mm shaft
- Two rows of eight steps - Channels A and B
- 5mm Blue (or any other colour!) LED's
- Minature chrome and black knobs
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Site Options
Resources
* Polyfusion 2040 Schematics 
* AM1040 Schematics
* AM1040 Project Notes