Wireless Set No. 52 Canadian - Project

[Bruce MacMillan]

I don't have access to a Canadian WS9 anymore but the schematic shows a similar style of connector as the WS52.

CMC only built the receiver for the WS9, the xmtr being built by Northern Electric. That would suggest that there was a third party manufacturer or somebody shared the product. Both companies had the capability to produce them.

[David Dunlop]

That’s interesting news, Bruce. I was not aware of that production sharing for the Canadian Wireless Set No. 9.

There is an illustrated parts list on the British Royal Signals site for the Canadian No.9 Set I have requested a copy of, so will see what it shows for looks and nomenclature, compared to the 52-Set Cdn for these connectors. Then, with some luck we might be able to push the references back to what STC in England was doing.

David

[Chris Suslowicz]

Originally Posted by Bruce MacMillan

I don't have access to a Canadian WS9 anymore but the schematic shows a similar style of connector as the WS52.

CMC only built the receiver for the WS9, the xmtr being built by Northern Electric. That would suggest that there was a third party manufacturer or somebody shared the product. Both companies had the capability to produce them.

Given that the remote receiver was usable as a spare for the set receiver, and that the WS52 and WS9 remote receiver power cables are virtually interchangeable, I'd say the connectors are identical in construction, if possibly different in pin configuration. Whether they're an exact copy of the ones used in the STC-built WS9 is another matter, but I would not be surprised to find that they were.

Chris.

[Tim Bell]

Chris

You are welcome to inspect my Canadian Ws9 anytime.

Cheers

Tim

[David Dunlop]

Finally got back to some thinking about the potential short in my Main Set Receiver Connector Socket this past week. In particular, the fact that I had noticed when connecting the Remote Supply Connector Plug to the socket, the retaining screw did not seem to run home as far as it did when I connected this cable to my backup receiver. That in turn got me wondering it this screw might be jamming on some loose bits inside and perhaps be part of the short problem.

Add to that, I was curious if it might be possible to isolate if the short was in the 12 Volt LT circuit, or the 150 Volt HT circuit. So I dug out my trusty old 2 Amp 12 Volt DC Trickle Battery Charger to jumper onto the 12 Volt circuit and see what happens.

I first tested the charger output. It was producing 11.78 Volts DC, along with 6.69 Volts of AC. I first jumpered it to the +12Volt terminal on the backup receiver socket and negative to chassis ground. The panel indicator lamp on the backup receiver lit straight away and I got a reading on the meter of 8 Volts DC LT. Turned on the calibrater and its indicator lamp lit and the meter reading dropped to 7 Volts and held. I waited a minute, switched off the calibrator and the meter went back up to 8 Volts and held.

I then switched the charger over to the Remote Receiver and jumpered it up in the same manner. The results were virtually identical to the backup receiver.

I am pleased with those results. Next, I am basically going to repeat this test with the Remote Supply, using jumper cables for both the 12 Volt LT and 150 Volt HT circuits. Basically bypassing the physical connection of the Remote Supply Connector Cable to the receivers. Hopefully that will provide some further useful information.

And while I was mucking about with the Connector Socket on the back of the backup receiver, I noticed the long paper label that runs across the middle of it with the Terminal IDs printed on it was missing. A closer look in that area revealed a cast oval mark with 'CMC' in the middle of it, about one third of the way in from one end. Photo attached. Pleased to finally find one of these marks and hope to find more as the project progresses.

David

[David Dunlop]

I did the jumpered test of the Remote Supply to the Remote Receiver late yesterday and the receiver lit up beautifully. After about a 10 minute warmup, I took meter readings for the valves. All registered and 'look' to be in the right range of values, but to be sure, I sent a copy of the recorded values to a friend in Arizona who operates a 52-Set Cdn on the air on a regular basis to see how my readings compare to his receiver.

The audio seemed a bit higher in white noise than it should and part of that may be some oxide build up on the various control contacts from lack of use over the years. The audio from the crystal calibrator was a bit weak but the 1000, 100 and 10 Kc pips could all be heard.

The only fly in the ointment was a nil reading for HT on the meter. Likely suspect is the R58A resistor (or resistor pair as it turns out) may have gone South. Now if I can only figure out where the heck they hid the little sucker(s) on the chassis, I can test them and see how close I get to the rated 600,000 Ohm value.

At least I have narrowed the short down to being intermittent and internal to the connector socket. It's nice to make progress on issues.

David

[David Dunlop]

I had the Remote Receiver setup up and running again last evening for about half an hour. I will probably do this for the next week or so to give all the little bits a chance to get used to electrons moving about again, and also give me an opportunity to work switches and dials mechanically. I did notice the tuning dial has a small arc of stiffness at one point, so will eventually get around to disassembling it for a cleaning. Nice that they are identical mechanically to the 19-Set ones.

I hooked the receiver up to my dipole last night as well and was able to find WWV in Ft. Collins quite easily at 5.00Kc. The signal drifted in and out quite a bit and there was a lot of crud jumping all over it, but it was there. Some of that crud may, in fact, be some weak tubes in the set, but HF propagation recently has been quite bad as well.

David

[David Dunlop]

I have been running the Remote Receiver each evening for a week now, between 30 minutes and an hour each time.

The valve readings from the meter have stayed very close to those initially recorded when I first fired the receiver up. The background noise seems to have dropped off a bit on the loudspeaker when listening to the WWV Time Signal and this is still all with the RF Gain at 'maximum' and the AF Gain at very close to maximum. The crystal calibrator pips are still somewhat buried in the background noise.

I decided to add another test to the mix on the weekend by checking out my Receivers, Headgear, MC, Mk.1 in both PHONES sockets. I figured this would tell me what both sockets were up to, that the Receivers Headgear worked and that the toggle switch between the loudspeaker and the headgear also functioned properly. Pleased to report all items responded correctly, but one point did surface I am curious about.

This is the first ever wartime wireless set I have ever worked on/listened to that is equipped with an installed loudspeaker. What I noticed straight away was the level of background noise seemed much greater via the loudspeaker circuit than the headgear circuit. I had to back off the RF Gain nearly 1/4 from full maximum and the AF Gain by about 20 % from where these two controls were set for the loudspeaker, when I was listening to the set via the headgear. I also noticed that through the headgear, the crystal calibrator signal was very clear at all three positions compared to when listening with the loudspeaker. The speaker is identified as:

LOUDSPEAKERS, 3-in, PM, 3.5 Ohms

Now it is still quite possible that some of the valves are not fully up to standard and this may be influencing the level of background noise I am experiencing, but can anyone advise if, in general, it would be expected for a wartime era loudspeaker in a wireless set to have a noisier output than a set of headgear?

David