Al Krysieniel had an interesting item at the May MIT Flea – a General Radio 483-C Output Meter.
This is the ancestor of the classic 583-A and 783-A Output Meters. It has Melville Eastham's classic switch design with external wiper and contact studs, rather than the modern variant with internal contacts. Aside from the internal location of the contacts, the modern variant looks to me to have exactly the same design of the switch wiper and contacts as Melville's original design.
The classic General Radio wire-wound resistors. These look like they are on phenolic strips rather than mica cards.
Unlike its successors, the 483-series lacks a transformer to provide selectable load impedances. The 483-A provided a 4000 ohm load, the 483-B provided an 8000 ohm load, and the 483-C provided a 20,000 ohm load. They were introduced in catalog F3, dated October 1, 1931.
Catalog F3 page 1. Click the image for a hi-resolution PDF image.
Catalog F3 page 1. Click the image for a hi-resolution PDF image.
Here's Al on the right with a prospective customer. Those walnut cases with the French polished shellac finishes are just beautiful.
Al was a former employee of the General Radio Company. In the 1990's and early 2000's he advertised in Antique Radio Classified as "Acton Service Company", offering repair service for General Radio equipment.
We chatted for a while at the Flea. Al told me that he started at General Radio as an assembler. At some point, he asked to move to the service department, and was granted a trial. He apparently succeeded and remained in the service department for the rest of his career at General Radio.
Al related that when General Radio introduced a new instrument, they would build a prototype run of twenty-five and send them out to respected engineers in the industry and ask for their evaluation. Of course they all met the specification when they left the factory, but sometimes things would go awry. Al said that the engineer would use high-quality components when developing the instrument, but that the purchasing department would sometimes save a nickle by purchasing some other brand. Sometimes that worked, but sometimes it resulted in the prototype instruments coming back.
Al was responsible for repairing any that came back as non-functional or not meeting specification. He said that on more than one occasion, all twenty-five came back. Al said on a couple of occasions he saw the design engineer cry, from the frustration of trying to understand why their design wasn't working in the field. Al told me that on those occasions he was glad to be just a technician rather than an engineer responsible for making the instrument work.
I asked Al if he was aware of any attempt to preserve a collection of General Radio gear (other than his basement!). He told me that IET Labs (the company that purchased the General Radio instrument line) is owned by two brothers, one here in West Roxbury, Massachusetts and the other on Long Island, NY. Al told me the brother in West Roxbury has some instruments on display, and that the brother on Long Island has a lot of gear stored away but no space to display it. I hope that some day a museum is created dedicated to preserving the history of electronic laboratory instruments, including the contributions of General Radio.