[R-390] IERC Tube Sheild - Brand New

[Roy Morgan]

At 11:02 AM 8/4/2006, n4buq at knology.net wrote:
>Does anyone know which tubes in the R390A take this size shield (or better
>yet, how many of this size are needed in an R390A)?

Barry,

There is a better list but I can't find it just now:

(original author unknown)
R390A Tube Chart

  Tube  BETTER Function  Shields

  V201  6DC6    RF Amplifier  5020-B
  V202  6C4  6100  First Mixer  5020-B
  V203  6C4  6100  Second Mixer  5020-B
  V204  6C4  6100  Third Mixer  5020-B
  V205  12AU7  5814A  Calibrator Osc  6020-B
  V206  12AU7  5814A  100KHz Osc  6020-B
  V207  6AK5W  5654  First Xtal Osc  5015-B
  V401  6AK5W  5654  Second Xtal Osc  5015-B
  V501  6BA6W  5749W  First IF Amplifier  5020-B
  V502  6BA6W  5749W  Second IF amp  5020-B
  V503  6BA6W  5749W  Third IF Amp  5020-B
  V504  6AK6    Fourth IF Amp  5020-B
  V505  6BA6W  5749W  BFO  5020-B
  V506  12AU7  5814A  Detector  6020-B
  V507  12AU7  5814A  Limiter  6020-B
  V508  6BA6W  5749W  AGC Amp  5020-B
  V509  12AU7  5814A  IF Cathode  6020-B
  V601  12AU7  5814A  First AF Amp  6020-B
  V602  12AU7  5814A  Second AF Amp  6020-B
  V603  6AK6    AF out local  5020-B
  V604  6AK6    AF out line  5020-B
  V605  0A2  6626  Voltage Reg  5025-B
  V701  6BA6W  5749W  VFO  5020-B
  V801  26Z5W    Rectifier  6020-B
  V802  26Z5W    Rectifier  6020-B
  RT510  3TF7  TJ311M01  Current Reg  6025-B

Above is a little chart I made up of the R390A's tube complement and 
equivalent tube shield required. The tube shield numbers given are for the 
IERC black shields - the ones preferred to disipate the heat produced by 
the R390A tubes. The shiny metal tube shields should not be used because of 
poor performance and the reflection of heat back into the tube - however, 
the black IERC tube shields are now hard to find.



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