Created by Western Graphics Last modified 08 February, 2006
AM1027 Module - ARP Clocked Sequential Control
Overview This module is based on the analog sequencer from the ARP 2500 synthesizer, the ARP 1027 module. The original was designed back in February 1971 and subsequently
revised over the next 3 years.
The new AM module is a close eplica with only one major change; 3 x 8 control voltages unlike the ARP module which has 3 x 10 voltages.
ARP 1027 Overview The original ARP module contains a ten-step decade counter, and three rows of potentiometers
to provide three independently adjustable voltage outputs for each step of the counter. The sequencer is driven from an internal voltage controlled clock, which also had variable pulse width. Pulse width
and clock speed can be controlled by an external control voltage. The sequencer can be stepped forward manually or via voltage control, but there are no reverse or random counting facilities. You can download the module manual for more
details.
Original Circuit The original schematics for this module show the sequencer was based around an early CMOS decade counter chip, with LM301 Op Amps providing the clock and voltage buffering,
whilst medium power transistors kept the lamps alight (no LED's on this one!).
AM Module The AM circuit is still under design...
Panel The front panel is a standard AM design, 180mm wide
and 4U high, with black lettering.
Build History The schematic is being transfered to Eagle CAD.
Specifications To be completed.
Resources
* AM FAQ's more » * Hard to find Parts more » * ARP 2500 Manual more » * Schematics are at the
ARP Tech site more »
* ARP 1027 Manual (222KB)
* AM1027 Project Notes
* AM1027 PCB layout Zipped .BRD Eagle CAD
* AM1027 front panel Zipped .FPD Front Panel Designer file
Original ARP 1027
Front Panel
AM1027 front panel
PCB - populated
AM1027 PCB populated and mounted to the front panel.
Site Options
ARP 1027 Overview The original ARP module contains a ten-step decade counter, and three rows of potentiometers
to provide three independently adjustable voltage outputs for each step of the counter. The sequencer is driven from an internal voltage controlled clock, which also had variable pulse width. Pulse width
and clock speed can be controlled by an external control voltage. The sequencer can be stepped forward manually or via voltage control, but there are no reverse or random counting facilities. You can download the module manual for more
details.
Resources
* AM FAQ's 
* ARP 2500 Manual 
* Schematics are at the
* ARP 1027 Manual 
