Some sellers on e-Bay will have you believe you can take a scrap, core, or As-Removed aircraft instrument and just pop it into your simulated aircraft instrument panel, hook up a few wires, and you've got yourself a working instrument.

Nothing could be further from the truth. I read e-Bay ads frequently stating, "great for simulator use!" While that may be true if you happen to own the latest Level-D simulator, they won't work for the rest of us.

In fact, just about the only aircraft instrument you will be able to use in a simulator is a mechanical clock. Possibly an electric clock too, if it's for 12, 24, or 28 VDC. Forget about airliner-type electric clocks.

Aircraft instruments require air pressure, (or lack thereof), or electrical power and a gyro platform or a built in gyro to operate. This means that even if you do manage to power one up from a rotating or static inverter, you'll have to have the ability to rotate your entire sim around the gyro platform. In addition, electric airliner-type instruments operate using 400 cycle power which you will not find at the electrical outlet in your home. If you try to power one of these instruments from 60 cycles you will destroy the electronics inside.

Unless you have a PhD in electrical and mechanical engineering and a background in aircraft instrumentation and nav equipment, as well as a well padded bank account, steer clear of buying these instruments for simulator use. They will not work at home.

Aircraft panels, however, are another matter. Many of these can be adapted for simulator use. Many use passive components only, such as indicator lamps and switches and are used only to control other pieces of equipment that use the 400 cycle power that you don't have.

Examples of this types of equipment would be individual panels from the overhead on most aircraft and many panels on the main instrument panel. Electro-mechanical equipment such as throttle assemblies, landing gear actuators, and trim devices can also be modified for simulator use. Also, steer clear of radio heads, transponders, and other communications equipment. This type of equipment is not impossible to modify, but you need a good background in electronics to make it happen. Communications equipment in the cockpit is nothing more than a control head for a remotely mounted transceiver or other type com device.

You could think of it in this manner: if it requires 400 Hz 115VAC power, don't buy it for simulator use. Anything else is possible including anything running from DC. Power supplies can always be found on e-Bay at the required DC voltages for aircraft equipment.

There are several manufacturers of simulated instruments for the home builder. Many also use a monitor(s) behind the instrument panel and create the full-size instruments using MSPS. Still others use dedicated and expensive software for the new glass cockpit displays.

I hope this short guide will keep the person contemplating a simulator build from wasting their money on instruments and equipment that will not work in the home simulator.