The IC3600AOAC1F Amplifier in the Mark I-II Speedtronic

The IC3600AOAC1F is an operational-amplifier board from GE's original Speedtronic turbine control, the Mark I and Mark II. The AOA line is a dual operational-amplifier card: it carries op-amp analog circuitry used to amplify and condition the low-level signals that the early Speedtronic system works with. In an analog control generation like this one, where functions such as speed, load and temperature loops are handled in hardware rather than software, an amplifier stage like the AOAC1F is what raises a small sensed signal to a usable level and shapes it for the control and protection circuits around it.

The board connects to the rack through a row of right-angled pins along one long edge and is built in the through-hole analog style of the IC3600 family. Documented examples of this card carry trim potentiometers, several transistors (some fitted with heat sinks), aluminum electrolytic and film capacitors, and both carbon-composition and metal-film resistors, many mounted vertically. It is stamped with the GE logo and an etched board-identification number. This unit is offered used, cleaned and tested.

Diagnose the Loop Before Swapping the AOAC1F

An amplifier card is easy to blame when a loop reads high, low or drifts, but the cause is frequently outside the board. Because the AOAC1F carries trim adjustments, a calibration issue can look exactly like a hardware failure. Check these before you pull the card:

• Trim and calibration. The board's trim potentiometers set gain and offset for the loop. A drifting or out-of-range output can be a trim that has moved or a loop that needs re-calibrating to the OEM procedure, not a dead amplifier. A replacement card will itself need to be calibrated to the loop after fitting.
• Edge connector. The right-angled pins along the board edge and their sockets can oxidize and lose contact pressure over decades. Reseat and clean before deeper diagnosis.
• Power rails. Op-amp stages depend on stable supply rails from the Mark I-II self-contained supply. Confirm the rails are present and steady; a weak supply will distort the output.
• Input signal. Verify the signal arriving at the amplifier. If the input is already wrong, the fault sits upstream in the sensor, wiring or the card feeding this one.

IC3600AOAC1F Part Number and Board Revision Codes

Break the number down as IC3600 (the Mark I-II Speedtronic family), AOA (the operational-amplifier function), the C sub-letter for the AOAC variant, and the trailing 1F revision code. The sub-letter and the trailing characters identify a specific GE revision, and different AOA sub-letters are not automatically interchangeable, so match the complete number to the board you are replacing. Where a source does not document a specific difference between variants, we describe the suffix as a revision or variant to be matched rather than inventing a distinction. The etched GE drawing and date codes on the board are the final confirmation.

Our GE Speedtronic Part Number Decoder explains how the IC3600 numbering is structured, which helps when an old drawing or spares list names a card you need to cross-check.

Companion IC3600 Analog Cards

The amplifier card is one stage in the Mark I-II analog chain. Around it sit input buffer cards, analog interface cards, function generators, set-point cards, D/A converters and logic boards, each performing a single job between sensor and output. Tracing a loop fault usually means following the signal through several of these stages. Browse the related boards under GE Mark I-II IC3600 Cards, and the full Speedtronic range under GE Speedtronic Turbine Control Boards.

What to Include in Your IC3600AOAC1F Quote

So we can confirm the exact board, please send the full part number IC3600AOAC1F, any revision or etched board codes, a photo of the board label and markings, your turbine model, the Speedtronic generation (Mark I or Mark II), the quantity and how urgent the requirement is. This card is offered used, cleaned and tested, as listed in the table below.

Select Request a Quote and we will respond within 24 hours. We deliver worldwide on DDP terms and accept purchase orders.

General Information about the Product
Part Number	IC3600AOAC1F Mark I-II IC3600
Description	IC3600AOAC1F By GE Speedtronic IC3600AOAC Dual Operational Card
Condition	used Clean and Tested With 1 Year Warranty.