Wireless Set No. 52 Canadian - Project

[David Dunlop]

So this weekend is the time for me to align and calibrate the Remote Receiver for my 52-Set. First step will be doing the two IF Coil Assemblies and see where that leads things.

The RF Input Signal I will be using this time will come from my early 1950’s Stark Signal Generator. I tested it out a few days ago and found it is very well calibrated, compared to my Canadian Model SG-1 Signal Generator. I need an output signal of 420 Cycles with a 400-cycle modulation. 420 Cycles is well below the frequency range of the receivers I have on had, but I realized I should be able to tune in the 5th Harmonic of that signal at 2100 KC on the Remote Receiver. I was indeed able to find it and it was exactly at 2.10 MC on the Receiver Dial, which told me the 420 Cycle setting on the Signal Generator, was spot on.

Getting a test signal into the receiver is the start, but you need a good reference output to adjust to. The recommendation is to bypass the speaker entirely and use one of the Phone Sockets to put a meter across and tune t the optimum deflection on the meter.

As it turned out, one of the other vintage bits of test gear I have had sitting quietly on a shelf over the years is a 1945/46 SOLAR Model CF Exam-eter. Its primary claim to fame all those years ago was it was one of the first pieces of test gear that could accurately test capacitors while they were still fully connected to their circuits. Typically, without such a piece of test gear, one has to remove one end of the capacitor at the very least, or completely remove it to get an accurate reading. As well as testing capacitors, this Meter does all the other things a VTVM can do and more. What caught my eye when reading the manual last week was that this meter can be used for Alignment Work.

Since I am going to have to go though the alignment process with this receiver 2 to 3 times to really fine-tune it (and go back one more time to redo the Main Set Receiver). I thought a more permanent Test Lead would be in order, rather than jury-rigging something temporary.

What I came up with is built around what the Eagle Eye Wireless Owners out there will recognize and the cord from a Morse Key No. 9 that I had parted out some years back and if I ever need it for its original purpose again, it is very easily restored back to original condition.


David