Fixing the shutter line

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his information is for the very few clients who had QM2000 boards with faulty shutter lines. These boards were shipped between February 10 and 16, 2000. Pangolin has already notified clients with these boards. If you have not received notification, then your board does not have a problem.

What is affected

The problem affects the shutter output, which is pin 13 on the QM2000's ILDA connector (DB25-F parallel-port-type connector). Normally, the shutter output is TTL level, 0 to +5 volts. But due to a fault in the Feb. 10-16 batch of circuit boards, the shutter output remains unchanged at -10 volts. This voltage should not damage the shutter. But since it does not change, the shutter cannot operate properly.

Repair options

• If you do not use the shutter line, you do not need to have the board fixed.

• If you do use the shutter line, or you want the fix performed anyway, we will fix the board at no expense to you. Simply send your board back to Pangolin for repair. Use our FedEx account number, 1174-5187-9, for the shipment. For shipments coming from outside the U.S., please be sure to mark the shipment "Returned for repair" so the correct customs duties can be charged to us. We will repair the board within a day or two of its arrival, and send it back to you via FedEx.

• You may consider fixing this problem yourself. You can do this if the fix is performed by a qualified technician with professional soldering equipment and experience. The rest of this page describes the repair.

MAKING THE REPAIR

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he repair involves cutting one circuit board trace on the back of the QM2000, and then cutting a trace and making two "solder bridges" on the front of the QM2000 board.

Back of the QM2000

The fix area (green above) is easily identified by the two yellow components on the back. Use the animation below to identify the trace to be cut. With an X-Acto or similar hobby-type knife, cut the trace. You may need to scrape out a small section, to be sure the trace has been fully severed.

Front of the QM2000

The fix area (green above) is on the left side, just above a large DC-to-DC converter, and to the left of chip U341. You will cut a trace, then make a solder bridge between two chip leads, and finally make a solder bridge between a chip lead and a resistor. The animation below shows these three steps.

Testing the fix

Install the QM2000 board, and run the LD software. When a frame is being displayed, the voltage on pin 13 of the QM2000's ILDA connector should be +5 volts. When no frame is displayed (no points), there will be no voltage.