Hello,

A few years ago I acquired a Chicago TC-532 Tube and Set Tester but only just recently spent time with it. Although it is not shown on RM.org, does anybody have information on this unit? I have already attempted an internet search without success but can offer the following update for RM.org:

The original address for this company was 536 W Elm Street, Chicago Illinois. That location is now apartments. The RM.org site indicates Industrial Instrument Service Corp (IISC) in Chicago as the manufacturer. This is an error. Although this company is 71 years old it is still too new for some of the equipment shown on our site. I contacted the owner of IISC and they confirmed they are not the manufacturer of the Chicago named company. They did suggest I try ALCA Industrial Instruments and I did speak with their owner. He indicated that ALCA is also NOT the old Chicago company.

Interesting note: at one point early in their histories IISC took legal action against ALCA because of similarities in the original names. Later, these companies did work together for a period. Not relevant for this discussion but interesting I thought.

I will suggest a new model once the site is corrected and post photos of the tester as well as part of the original owners manual that somehow survived water damage.

R/

Mark

Attachments

• Chicago TC532 Manual Incomplete (816 KB)

Great find — the TC-532 is indeed one of those elusive pieces that doesn’t show up in the usual references. The paperwork you shared is particularly valuable, since it ties the unit directly to the Chicago Industrial Instrument Company, 536 W. Elm Street, Chicago, Illinois. That confirms it was not Industrial Instrument Service Corp (IISC), as sometimes assumed.

From the sheet, it looks like the tester was marketed as both a tube tester and set analyzer, with dedicated positions for “Tube Test” and “Set Test,” which puts it in the same category as the small shop “combination” testers of the early 1950s. The instructions are consistent with other lower-cost service bench units: slide switch for function, plug tube into octal socket, adjust line as needed, and interpret results off the meter.

Given the style and the language, I’d place manufacture somewhere in the late 1940s to early 1950s. Chicago was full of small instrument and meter companies at that time, many of whom only produced a handful of models before disappearing. It’s not surprising that TC-532 documentation is nearly absent online.

Your manual fragment is a great piece of provenance, and I’d encourage you to post the full scans and chassis photos to RM.org once the correction is in place. That way the Chicago Industrial Instrument Company gets its own entry, and future collectors won’t confuse it with IISC or ALCA.

So, while schematics are still elusive, what you’ve uncovered already — name, address, operating sheet, and survival of a working unit — is more than most of these small Chicago testers can boast.

How should we proceed with the edit? Do we leave this manufacturer page as is and I suggest a new manufacturer or suggest a change to this manufacturer page?

Thank you,

Mark

A new maker's page but notes on both with links?