I do not own any Aries modules but recently repaired four modules.   Aries modules were available both as kits and factory modules.  These four modules appear to be kits due to the non-uniformity of components and wires as well as some build errors.  There is some Aries information available at leinermedia.net and also at Synthfool.

There isn't a lot of information available on Aries modules so I decided to create these pages with photos, information, and modifications.  On average, each module took 4 hours to repair.  My time was equally spent tracing the circuit and finding the fault, repairing and verifying functionality, and sometimes modifying the circuit to bring it up to specifications.

Tracing the circuit was slow since I did not have PCB layout information.  My initial assumption was that these modules had functioned so I was on the search for defective components.  It soon became clear that there were original kit build errors and later faulty repairs.  I eventually had to verify every FET and transistor type, pinout and orientation, and all other component values.  Some PCB pads had lifted which cracked traces leading to intermittent operation.  These modules were only as good as the skills and talents of the original kit builder.  The original soldering had bridges, cold solder joints, and in one case a tin whisker!  There were mechanical problems as well which shorted traces and interfered with components.

After the repairs the VCO and LFO have some of the cleanest waveforms I have seen.  The AR-317 is very stable and showed no signs of drifting.  Its nice to see vintage modules come back to life.

Aries AR-312 Envelope Generator

Aries AR-317 VCO

Aries AR-318 S&H / Clock / Noise Generator

Aries AR-324 Dual LFO / Lag / Inverter

General Repair Tips

10V Signal Levels

These modules are designed for 10V signal levels.  The AR-312 Envelope Generator would not gate at all with a 5V level but would trigger most of the time with a 5V level.  It is easy to forget this if you are interfacing these modules with other gear.

2N2393 Transistors

For whatever reason, there were many more NPN transistor failures than PNP.  Even the NPN in the potted exponential converter failed.  These modules had previously been repaired and I needed to redo all the NTE85 transistors which had been substituted for 2N3393.  The 2N3393 and NTE85 pinout is E-C-B according to the datasheet but the PCB is designed for E-B-C.  A quick check of the original 2N3393 transistors have a E-B-C pinout with a dot to denote the emitter.  Be careful - you need to find original datasheets that show the pinout of vintage transistors or you need to trace out the PCB from the circuit diagram.

PCB Pads

There were a lot of lifted pads on the PCB and some had hairline cracks that were difficult to find.  There was even a tin whisker shorting adjacent traces.

Mechanical Problems

The PCB slides into two plastic rails mounted along the edges and is secured with two angle brackets and screws.  There were several instances of mechanical interference between the chassis and PCB components.

Other Aries Information

Contact me if you have scanned Aries documentation you wish me to host here.  I would especially like to have PCB layout information.

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