5R4GYB BROWN BASE

38.00 USD

Best on the market brown based 8 pin octal rectifier tubes manufactured in the United States by RCA. These excellent full-wave rectifiers come with black plates, rugged steel structure, and top halo getters. They are printed in red on base RCA and coded 7222, indicating 1972 production. They are also glass etched 5R4GYB U.S.A. Boxes are standard new style RCA red printed 5R4GYB.

Condition

New Old Stock (New in box)

	Tube Matching 6.00 USD by tube
LEARN MORE WHY ? A tube may have one, two, or three internal sections depending on the purpose of the tube; somtimes these sections are all the same, sometimes they are different. Due to manufacturing and material tolerances, there may be slight differences between the original specification and the actual tube. Tube matching tests each one of these internal sections and selects tubes, compared to original specifications at manufacture, for balanced performance and good sound. HOW ? All our tubes are tested by us prior to packing on our Stark, AVO, Simpson or RF Laboratories Inc. calibrated testers. On request for tube matching, tubes are matched for Mutual Conductance in Micromhos and Plate Current in Milliamps on our Amplitrex or Radioelec Duovac testers, with results printed for each individual tube. Certain tubes difficult to test are matched for Mutual Conductance in Micromhos only on one of our regular calibrated testers. On request we can also test for Microphonics.