Supreme I-177 B   Tube Testers      Hickok 6000A

Mutual Conductance Tube Testers

My Supreme Instruments I-177 B tube tester (above left) is used to test most older vacuum tubes including antique 4 and 5 pin tubes (01A, 83, etc.). The I-177 series testers were well built, military testers which utilized the mutual conductance test circuits designed by Hickok. They were produced by several manufactures for the military including Hickok and Supreme Instruments. This I-177 B was manufactured by Supreme around 1950 and has a booklet with the tube settings in the cover.   My Supreme Instruments Collection

You will also see a Triplett 2413 tube tester on the bench that I use for non-critical "quick checks" like shorts and open/close checks on eye tubes. This reduces the wear and tear on my more expensive tube testers. Test data for all my tube testers is also stored and searchable on the workbench computer to speed up finding tube settings and reduce the wear and tear on the testers paper roll charts and booklets. I also have over 100 early tube testers from various manufacturers in my Vintage Test Equipment Collection.

Many older radios and some radio test equipment were wired with a "Hot" chassis. An upper workbench AC outlet is isolated from the main AC power through a 500VA isolation transformer. This helps protect me from shocks when working on old radios. The variable AC supply (VARIAC) lets me bring the voltage up slowly in older equipment when I first power it up to help limit damage to the circuits if an old component fails.
Voltage and current meters on the variable AC supply allow me to monitor the power draw as the line voltage is brought up. A light bulb is also kept in series in the AC supply line to act as a ballast. If a radio starts to draw too much current as the voltage is increased, the amp meter reading on the supply will increase and the ballast light bulb will start to glow and let me know there is a problem. I use a clear glass 100w light bulb so I can easily see any change in the filament's glow. If you don't have a variac, you can bring voltage up in steps using a "Dim Bulb Tester" that you can construct for just a few dollars with some light bulbs, a cord, and an AC socket.

Some equipment I build myself (not kits). This audio generator helps test amplifier circuits and sound equipment. It produces sine, triangle, and square waves with adjustable audio frequency and amplitude.

I built the breadboard above to test transistor and digital circuits and to temporarily replace components in low voltage circuits under repair. It has a fixed 5V power supply, an adjustable +/- DC supply, a pulse generator, LEDs for monitoring digital circuit status, plenty of switches and I/O connectors for jumpers, and a Digital Volt Meter.

This simple "Lamp Test Jig" which I made with several different style lamp sockets and connectors for meters and power supplies, saves me a lot of time testing lamps. I can easily test filaments and current draw on bulbs and fuse lamps without using a mess of jumpers and alligator clips.

GE #81 Fuse Lamp under current test

This tool kit keeps all my hand tools organized. The Xcelite TC-100 tool kit originally came in a briefcase. I had an Anvil road case custom made for it that is deep enough under the tool pallet to store larger items, meters, and testers. Its held up well despite several years on the road when I was a pro sound engineer. I think that if the house was burning and I could only grab one thing from my antique radio collection or workbench, this would be it.

I use a Weller WTCPN soldering station on the workbench along with a Weller 8200 N soldering gun for heavier duty soldering. You can check out some of my soldering tools here: Soldering Tools, Irons, and Guns

Several thousand vacuum tubes are kept for rebuilding radios and vintage test equipment. Once tubes are tested, they are stored in my tube cabinet (an old auto parts cabinet) or in one of my Radio/TV repairman's tube caddies.

I've been asked why my repair bench looks so neat and clean. All I can say is when I need something, I don't like looking all over for it. Just ask the kids...

My repair bench computer contains files of updated tube testing data for all my tube testers along with thousands of radio and test equipment schematics, parts lists, and dial string diagrams. Internet access comes in handy when I have to search for additional information or manuals I don't already have in my service library. The web site work and digitizing of service manuals is done on separate computers in my office. All computer workstations in the ofice and shop are networked for sharing files of equipment data and for Internet access.

One of my networked office workstations

I keep an extensive library of over 350,000 original factory service manuals and schematics covering radios, amplifiers, phonographs, and test equipment from the the 1920's, 30's, 40's and 50's. My collection includes complete libraries of service information published by Gernsback, Riders, Beitman, early Howard W. Sams, and the original factory service manuals from major manufactures such as Crosley, RCA Victor, Motorola, Philco, GE, Marconi, Atwater-Kent, Zenith and many others. I also have vacuum tube manuals, tube substitution books, and cross reference manuals for finding information such as tubes cross referenced by manufacture, model, number of tubes and type for help in identifying unmarked radios. If you need schematics or service information for restoring your antique radio visit my factory service manual site at: www.AntiqueRadioSchematics.org Originals and downloads of SAMS Photofact service manuals for radios manufactured after World War II are available at my Photofacts web site: TheSchematicMan.com

Sawdust, striping chemicals, and drill bit shavings don't mix well with electronics and test equipment so I keep them far away from each other. All radio cabinet repair, refinishing, and any chassis metal work is done out in my wood shop. A 12" drill press, belt and disk sander, scroll saw, router table, and band saw are my most used power tools for cabinet repair.

Remember to check out some of my vintage test equipment collection.