Help identify gaps?

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Original poster: "J. B. Weazle McCreath by way of Terry Fritz <twftesla-at-qwest-dot-net>" <weazle-at-hurontel.on.ca>


Hello Coilers,

A friend of mine who just recently got into coiling gave me two
devices that he'd like identified.  They appear to be vacuum
spark gaps, based on their appearance, but I do have some data
off them:

No. 1 - Philips 4372, is 2.5" long overall, 0.75" dia. and has
        a pair of half-sphere sheet metal electrodes spaced
        about 0.015" apart

No. 2 - Philips 4390, is 3.75" long overall, 1" dia. and has
        two heavy cylindrical electrodes about 0.5" dia. and
        0.5" long supported by rods of 0.2" dia.  The gap is
        not visible due to gettering on the glass envelope.

Any ideas as to exactly what these devices are and what their
ratings might be?  Any info is appreciated.

73, Weazle, VE3EAR/VE3WZL
G-1#1214

Listening: 147.030+ and 442.075+
E-mail:    weazle-at-hurontel.on.ca
           or ve3ear-at-rac.ca
Web site:  http://www.hurontel.on.ca/~weazle