Here's a publication entitled, "Characteristics of Sylvania Receiving Tubes." There appears to be no date of publication; however, my instinct tells me it's from the early to mid-Fifties. On page 3 there is a very brief instruction on how to use the charts to determine the operating characteristics of the radio and TV receiving tubes manufactured by Sylvania, eventually part of General Telephone & Electronics (GTE).
The inside front cover contains several nice (albeit small) photos of the plants where these vacuum tubes were manufactured. I seem to recall that Sylvania also had a plant in Lancaster, Pennsylvania. This manual is obviously used but in good, page-turning, readable condition. I made repairs to the front and rear covers, nearly invisible.
Publisher: Sylvania Electronics
Year of Publication: 1950s, est.
Physical Size: 8-1/2" by 11"
Number of Pages: 96
Cover Material: Paperboard (soft)
Price: $8.50, plus $3.50 shipping
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