RCA 5V4G Rectifier Tube, 1949, in a Sylvania Box
Archived listing from the original vintage-amplifier.com. Prices, seller details and purchase links have been removed; this page is a reference record, and nothing here is for sale. About this archive.
1 ea. (Single) 1949 RCA 5V4G Rectifier tube. Tested New and comes in a Sylvania Box. It was stored like this for many years, unused. This is exactly how I found it. Made in USA. Date Code is 9-22. Tested on my calibrated TV-7D/U Tester, Readings were 64 / 65 where 40 is the minimum on a TV-7. Excellent, bright, shiny getter flashing. NO Shorts or gas, no loose particles, no loose base.
About this model
The 5V4G is a full-wave rectifier, the tube that turns an amplifier's AC supply into DC for the plates. This single RCA example carries a 1949 date code and came in a Sylvania box, new and unused. The seller tested it on a TV-7D/U, the US military mutual conductance tester, and recorded 64 and 65 against a minimum of 40, with no shorts or gas.
The 5V4G sits between the 5Y3 and 5U4 in current capability and turns up in many 1950s American amplifiers; the archive's Heathkit W4-AM uses one. When replacing a rectifier, keep to the type in the manual, because swapping types changes the supply voltage.
| Maker | RCA (in a Sylvania box) |
|---|---|
| Type | 5V4G full-wave rectifier |
| Date code | 1949 (listing) |
| Test | 64 / 65 on a TV-7D/U, minimum 40 (listing) |
Questions collectors ask
What does a 5V4G tube do?
It is a full-wave rectifier: it converts the AC from the power transformer into DC for the amplifier's plates.
What is a TV-7 tube tester?
A US military mutual conductance tester widely used by collectors; readings are compared with a minimum value for each tube type.
Sources: Heathkit Virtual Museum: W4-AM; Wikipedia: Tube tester.
