McPHAR 127 Power Supply

Hello all,

Does anybody have any information on this unit? Seems to date back to the late 40's or early 50's. Meters full scale indicate 500V and 300mA. Uses 2x 83v, 4x 6L6G, 1x 6SN7 & 1x NE56. Any info appreciated.

Art
 

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I'd even say 1936 (6L6) to 1940 (5V4 edges-out 83V). But the 6SN7 snuck-in 1939 to 1941, so early WWII. If this were mass-produced it is hard to picture relying on supplies of the 83V. True, maybe Mr McPhar bought a crate of 83V in early 1936 and was determined to use them (and their 4-pin sockets) up before buying 5V4. But there was very little "surplus inventory" through WWII; anything not sold for military went to patching-up civilian radios which could not readily get new tubes.
 
The big soldered sardine-can filter capacitor is a Canadian made Aerovox and is dated 1948. Unless it was replaced with an exact replacement, it's definitely original to the unit. And the 1953 "calibration due" sticker is a bit of a giveaway too,haha.

Keep in mind that Canada has a much smaller economy than the US, and (especially in that era) industry and consumers tended to continue using outdated equipment, so we kept manufacturing spares long after they were superseded by the "newer and better" versions.