TEST EQUIPMENT

The following is some of the test equipment I have acquired or built over the years. Most of it is almost a necessity in the equipment repair and renovation work.

A variac is a necessity when powering up equipment that hasn't been used in a long time. Slowly bring up the line voltage will allow electrolytics to reform or prevent a high surge input current if there is a problem.

A line isolation transformer is used to prevent shocking situations when you have faults on primaries of power transformers or 'hot chassis'. This one is rated at 500 watts load.

This line isolation transformer is rated at 1500 watts for those really big loads. Actually, I feed all the outlets on my workbench from it.

This is a Simpson Model 467 True RMS Digital Multimeter picked up from that E-place at a very reasonable price. I use it as a general purpose multimeter. You need to accurately measure voltages and resistances.

This is a Heathkit IT-2250 Digital Capacitance Meter I built. Useful for checking out capacitor values, can resolve 1 pF readings on the lower range if you don't move the leads!

Picked up this B+K Precision Model 820 Capacitance Meter from an estate sale as a backup for the Heathkit and because it was 'almost free' in new condition.

This is an HP 400EL AC voltmeter that can read from very low level to pretty high voltages over a wide frequency response and high input impedance. Good for doing frequency response checking.

General purpose HP 5381A frequency counter. What more can you say about a counter...

This is one of the most useful pieces of test equipment that seems to be generally unknown. It's a HP 428B Clip-On DC Milliammeter. You can measure DC currents from microamperes to 10 amps by merely clamping the probe over the wire. There's no need to disconnect the wire and place an ammeter in it. Measuring DC currents was never so easy!

This is a Radio Shack 21-527 RF SWR and Power Meter. Lots of folks have knocked RS stuff, even I find faults with some of their stuff, but this meter has been a real charm. However, you have to look hard for one; it's been discontinued for awhile.

This is a homebrew antenna bridge I built that can provide impedance levels for the antenna you're trying to set up.

This is a homebrew grid dip meter that can determine resonant frequencies of tuned circuits or antennas. It is a solid state device so there is no true 'grid' inside. I have wound coils for it to cover from 2 thru about 40 MHz.

A Fluke 100:1 High Voltage probe for measuring those big plate transformers or getting a really high input impedance.

A TS 1771/U 50-ohm RF load good up to 150 watts continuous. Used for checking out the transmitters.

An AN/URM-25D signal generator that will generate signals from 10 KHz up to about 50 MHz. Used for alignment of receivers and transmitters. I have re-capped this unit and purged it of all the paper and oil capacitors.

This is a deep cycle marine battery I keep around for working on 12 volt high-current rigs. High up on my to-do list is a line-powered, 1-18 volt 30 amp power supply. I plan to rewind an old microwave oven power transformer for the supply. Will post pictures of that project over on the technical page when we get going on it.

This is a Hickok Model 6000A tube tester in pristine condition. When you work on tube equipment a tube tester is a 'gotta have' item. Side line: I worked at Hickok many years ago as a co-op student in their tube tester dept. My job was to determine the roll chart and cardmatic data for new tube types that were introduced.

And when you work on tube equipment you need a good source and supply of replacement tubes.

Probably one of the most versatle pieces of test equipment, the oscilloscope. This is a Tektronix Model 475, dual channel, good to about 200 MHz. It was picked up off that e-place and cleaned up extensively.

This is an RCA Senior Voltohmyst Vacuum Tube Voltmeter. Quite popular many years ago, this one has been completely renovated and looks brand new unlike this picture of it. Although digital meters are nice, nothing beats an analog meter when aligning receivers and transmitters.

Every workbench needs an assortment of chemicals and cleaners to keep those old boatanchors humming. What we have here are lubricants, contact cleaners and restorers, freeze spray, canned air, plastic polish, and LOTS of Q-tips.

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