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1T4 / DF91 TOP GETTER
  • 1T4 / DF91 TOP GETTER
  • 1T4 / DF91 TOP GETTER
Philips

1T4 / DF91 TOP GETTER

9.00 USD
4.00 USD Save 5.00 USD

Quality miniature glass 7-pin entode tubes manufactured by Philips in Holland. These variable-mu pentodes are designesd for use as RF amplifiers. With top getters and silvered metal plates, these tubes are printed in white PHILIPS MINIWATT DF91. Late 1950's production, they are boxed in standard Philips yellow and blue boxes printed PHILIPS MINIWATT.

Condition

Tube Matching
Tube Matching
6.00 USD by tube

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.

Quantity

Philips
117 Items

Data sheet

Base
7 pin miniature B7G
Boite type
1/2
Emplacement
50
Quide
1331
Fonction
Pentode
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