Matched Pair RCA 6C8 6C8G Vacuum Tubes Valves 6SL7 Substitute NOS NIB XXD Loktal These four Philco engraved base

These four Philco engraved base number / type 27 tubes were tested on our Paul Hart-calibrated TV7/U for shorts

This Sylvania milspec / industrial 5814 / 12AU7 / ECC82 dual triode was tested on our Paul Hart-calibrated TV7/U for shorts

new in box RCA 4GJ7 / XCF801 tubes tested to spec on our Paul Hart-calibrated TV7/U

It is somewhat microphonic

Matched Pair RCA 6C8 6C8G Vacuum Tubes Valves 6SL7 Substitute NOS NIB XXD Loktal These four Philco engraved baseThis beautiful new old stock, new in box (for Tube One) matched pair of RCA 6C8G dual triodes was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. Transconductance measured 50 52 for Tube One and 53 52 for Tube Two where minimum (65%) is 25 25 and 100% is 39 39. They have dimpled, sheet getters; wire snubbers for lowered microphonics; smooth round bottom and top mica spacers; dark gray rounded