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Old 10-02-20, 19:09
David Dunlop David Dunlop is offline
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Join Date: Feb 2006
Location: Winnipeg, MB
Posts: 3,384
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Well I am finally catching up a bit on this project, but not without a fair amount of multi-tasking. Something I have never been very good at for long, without getting a major headache in the process and a large empty space in the wine cellar (for which I deny any correlation whatsoever).

The first thing I realized was the documentation of work in the 2nd to 4th Echelon Work Manual is comprehensive, but not organized in the best manner for actually recording test data results. Five tables of specifications relate directly to the 52-Set Receiver as follows:

Table 7 - Receiver Voltage Check
Table 8 - Receiver Resistance Chart A
Table 9 – Receiver Resistance Chart B
Table 10 – Crystal Calibrator Resistance Chart A
Table 11 – Crystal Calibrator Resistance Chart B

I have now transcribed the first three tables to Excel Spreadsheet format, adding in spaces for recording actual test results next to each specification. This makes saving the data for later analysis so much more efficient. I hope to have the two calibrator tables finished by next weekend.

In addition, this morning I was able to complete working through the data collection from my Remote Receiver for Table 7. This data is collected with all valves and lamps in their sockets and the chassis powered up. It took longer than I thought, for a couple of reasons.

First issue to arise, was realizing I had been away from working on my 52-Set just long enough to not remember the pin layouts of all the valve sockets, when viewed from the top, or bottom, of the sockets, and once I had sorted Pin 1 locations out, whether the pin count proceeded from that point in a clockwise or counter clockwise fashion. It took about four sockets before it all started to come back to me.

Since all valves are in place and the power is on, the only place to access the socket pins is from below the chassis. That seemed pretty good initially, as all valves except V1G and V1H can be accessed at the back of the chassis. The remaining two can be reached simply by tipping the chassis to either side to expose the bottom chassis assembly. But there is always and exception, isn’t there…and in this case it was two!

V1A and V1B sit quietly in the upper right rear corner of the chassis, directly behind the large Bakelite 8-pin Connector Socket. There is no way around it. The three small screws holding the connector backing plate to the upper right rear corner of the chassis have to be carefully removed and the Connector Socket assembly guided gently away to expose the two valve sockets beneath it.

That’s when the second issue surfaced. Once I was satisfied the Connector Socket assembly was safely out of the way of the two valve sockets and no exposed contacts on the assembly were touching anything they should not be, I turned the Remote Supply Unit back on. No Pilot Lamp and no Low Tension showing on the meter. My first thought was I had broken one of the wires on the Connector Socket, so carefully checked them all. They were fine. Then I remembered, the ground for the socket is through its backing plate being mounted to the receiver chassis. A quick addition of a jumper cable between the chassis and the backing plate and on came the Pilot Lamp and 12 volts showed on the meter. Data collection from the Remote Receiver for Table 7 has now been completed.

David
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