Wireless Set No. 52 Canadian - Project

[David Dunlop]

Hello Mike.

Interesting you should ask.

About 30 years ago, I ran across a Solar Manufacturing Corporation, Model CF CAPACITOR EXAM-ETER, with its matching calibrated manual that was headed to the Landfill. It was missing its test leads, which turned out to be critical for the proper operation of the instrument and it was not until 2019 that I ran across a chap in the States who also had this kit with leads. He gave me the specifications for the leads and I was able to fabricate a set.

The tester was made in 1946, vacuum tube driven and is capable of testing for Capacitance, Electrolytic Capacitor Leakage, Insulation Resistance, Resistance, DC Voltage up to 600 Volts and AC Voltages from 5 to 50 Volts.

The claim to fame for this tester back in its day was the ability to test capacitors in situ reliably, without having to disconnect them from their circuits to avoid biased readings from the related circuitry. I hope to be able to finally check out its capacitor capabilities with the 52-Set Project.

Currently, I have a basic multimeter able to provide capacitance readings and recently bought a Proster DIGITAL LCR TESTER Model BM-4070 to see what it can do. So far so good although in tight spaces, I find its probe heads much too large and clumsy to work with. I am interested to see how the Solar tester will compare to the modern kit when I really get into it.

David

[Mike K]

Is this the unit ? https://www.youtube.com/watch?v=Wje6Z2eOWng

[David Dunlop]

Affirmative, Mike.

David

[Bruce MacMillan]

The Proster and the Solar measure two different parameters. The Proster is good for measuring ESR (equivalent series resistance) which basically tells you if the electrolyte in the cap has dried up. The Solar can measure leakage at high voltage levels. Using the power factor you can calculate the esr as well. I would be more concerned with leakage as it can sometimes damage components like that nasty cap in the WS19 that takes out T2.

Still both are good tools to have on the bench. When the repair shop I worked at shut down I aquired a Sencore LC102 which does both.

[Chris Suslowicz]

I use a Peak LCR meter for checking values, and the companion ESR unit for series resistance. For electrolytics there's a 1950s-vintage "Reforming Unit, Electrolytic Capacitor, No.1" which will handle up to 350 volts or so, after which it's a matter of "drag the bench supply out" if I need to re-form higher voltage electrolytics (take them up to 350 on the reforming unit, then finish with the bench supply).

For non-electrolytics (waxed paper, paper in oil, mica, etc.) I have an Ionization and Breakdown Tester that will go up to 12kV (or 6kV AC). That's just used for Pass/Fail testing though - you can't fix those types of capacitors.

(The Peak units are semiconductor, so care is needed when using those - making sure there's no charge in the unit under test before connecting up is very important!)

Chris.

[David Dunlop]

The slow, but steady, disassembly of my Spare Parts Receiver 8349 is underway and it is already revealing some interesting bits of information.

David

[David Dunlop]

These two retaining brackets cannot be found in either version of the Master Parts List for the 52-Set Receiver. Odd, because they are clearly designed to be replaceable, if needed.

For lack of a description, I have simply referred to them as ‘Valve Shield Retaining Brackets’, as their intended purpose is to keep the shield assemblies for the two horizontal rows of valves in place.

David