Wireless Set No. 52 Canadian - Project

[David Dunlop]

Hello Bob.

I hope the snow is melting in an orderly fashion out your way these days.

Here are a couple of photos comparing the 19-Set Voltmeter on the left with the 52-Set Voltmeter on the right. Both are designed to mount in a 2-3/16 inch panel hole with 12, 4 and 8 o’clock mounting hardware positions, but the similarity pretty much ends there.

That panel hole arrangement was quite possibly standard on many wireless sets, but the meters for the most part would be custom designed to work with the circuits unique to each set.

It would also seem that wireless meters evolved quite a bit from simple indicators to quite useful diagnostic tools for the operator. These dual scale meters not only allow the operator to monitor input voltage to the supply on the smaller scale ( 6, 12 or 24 volts), the Low Tension side of things, but also the power supply output voltage on the larger scale, the High Tension part of the set.

The Low Tension would typically be the battery input voltage, which was also the filament voltage for the tubes. A drop in Low Tension voltage would warn the operator it was time to switch to the second set of wireless batteries and recharge the first set. Normal Low Tension readings with no output from the wireless would indicate a possible failure in one or more valves.

The meter on the 19-Set could also tell you when the set was properly tuned to the available aerial you were using and the relative strength of your out going signal.

The 52-Set meter could do all of that plus had a feature on the receiver meter switch that allowed the operator to test each individual valve in the receiver to see if it was in good working order. The Operator could also turn this switch to a ‘SENDER’ position and then use a similar switch on the Sender (Transmitter) to test the valves in that unit as well.

All that while brewing up his morning tea!


David

[Bob Carriere]

Never realized that the 52 set had such diagnostics features .....amazing how progress was made from one radio model to another.

Bob C.

[Mike K]

Meter info .

http://www.schoolphysics.co.uk/age16...oil/index.html

https://en.m.wikipedia.org/wiki/Galvanometer

[David Dunlop]

Well I found out late last evening that the meter I was curious about was manufactured by the DeJur Company. It was apparently founded by two brothers in the 1920's in Connecticut and eventually relocated to New York State. They seem to have developed quite a good reputation in the radio sector for their tuning capacitor design work and their electrical meters , which were highly regarded.

At some point the company became DeJur-Amsco and they are now very well known in the Photographic Industry for their Light Meters.

David

[David Dunlop]

Interesting articles, Mike. Thanks for posting.

David

[David Dunlop]

An interesting bit of 52-Set information made a surprise arrival this week.

I had asked a friend in Edmonton to document the data plates on his 52-Set for me whenever he had a chance, so I could pass the information on to Jacques Fortin, in Quebec, who is assembling a database of known surviving 52-Set components. The set in question was on a pallet on a high shelf in his shop with an array of M20 parts in front of it.

A forklift finally brought the 52-Set down to earth and photos of the data plates were received and sent on to Jacques.

The big surprise was the data plate on the Main Set Receiver, photo attached.

Not only is it unlike any other 52-Set data plate I have ever seen, the serial number is unlike any other 52-Set serial number I have run across. The composition of the plate is thin Bakelite, with the white lettering painted on the Bakelite. It is completely devoid of any references to Canadian Marconi and it’s part-numbering system, and it is not the normal four-digit number between 5000 and 9000 that one would expect.

My first thought was the plate was a fake, so I asked my friend to pull the receiver out of its Carrier No. 4 and check to see if a Mod Card was located in it, to see what it had to tell us. Indeed there was. Notice the second photo. The modifications to this set were not done until 1964. The modifications performed have been in existence since November 1945, when Modification 1 came into being: The Installation of the Modification Card Holder inside the component.

So my thoughts are that this 52-Set Receiver was build around the same time as all the other 52-Set pieces known so far, 1944, boxed up and stored somewhere in the Army Supply System, until it was put into service in 1964. When requisitioned in 1964, it was unpacked and the modifications needed were performed and the receiver delivered to whatever unit needed it. With this data plate in place from the start.

The other pieces of information my friend has about the history of the set are that he purchased it directly from the Crown Assets facilities in Edmonton when it was surplussed out and that the paperwork he got from Crown Assets confirm all the components he has were the complete set Crown Assets sold as a single unit.

Bakelite seems a very fragile medium to make a data plate out of, especially when it is thin. And the serial number looks very odd. It is almost like it identified this receiver as the 25th out of an unknown number built for an Order or Contract Number 4075.

I now wonder how many other 52-Set components are out there with similar Bakelite data plates. I cannot recall thin Bakelite ever being used for data plate material on anything before now. and why such a vague and fragile plate?

David

[David Dunlop]

I had to pass on one of these last year, as it simply wasn’t in the budget at the time it showed up for sale, However, a few weeks ago, a gentleman in Kent, England had a post on the internet with a number of NOS ones for sale.

My Daughter and three Granddaughters had given Papa some Mad Money to put towards my WS No. 52 Project for Xmas, so I was quite pleased to be able to order two Holders to replace the ones removed from the Remote Receiver and Main Set Receiver when still in service.

It’s always fun to find old stock with original packaging and these two holders were no exception. Each still has its factory tag attached with a small run of hemp cord. The tags read:

ZA/4250 HOLDERS, Watch, Multi-purpose Part, Qty 6


David