(RCA HB-3 data courtesy Paul Bigelow and John Shriver)
RCA Tenative Data June 20 - August 1, 1946
26D6 PENTAGRID CONVERTER
GENERAL DATA
Electrical:
Heater, for Unipotential Cathode:
Voltage.............. 26.5 ac or dc volts
Current.............. 0.07 amp
Direct interelectrode Capacitance:
Grid #3 to all other electrodes (RF Input) 7.5* uuf
Plate to all other electrodes (mixer output) 14* uuf
Grid #1 to all other electrodes (Osc input) 5.8* uuf
Grid #3 to Plate .30 max* uuf
Grid #1 to Grid #3 .15 max* uuf
Grid #1 to Plate .03 max* uuf
Grid #1 to External Shield and all other
Electrodes excepth cathode and Grid #5 2.9 uuf
Grid #1 to cathode and Grid #5 2.8@ uuf
Cathode to External Shield and all other
Electrodes except Grid #1 15.5 uuf
* with external shield connected to cathode
@ with external shield connected to other electrodes
Mechanical:
Mounting Position............. Any
Maximum Overall Length 2-1/8"
Maximum Seated Length 1-7/8"
Length from Base Seat to
Bulb Top (excluding tip) 1-1/2" +/- 3/32"
Maximum Diameter 3/4"
Bulb T-5-1/2
Base Miniature Button 7-Pin
Basing Designation for BOTTOM VIEW........7CH
Pin Electrode
1 Grid #1
2 Cathode & Grid #5
3 Heater
4 Heater
5 Plate
6 Grid #2 & Grid #4
7 Grid #3
CONVERTER
Maximum Ratings, Design-Center Values:
PLATE VOLTAGE.......................... 300 max volts
GRIDS No. 2 & No. 4 (SCREEN) VOLTAGE... 100 max volts
GRIDS No. 2 & No. 4 SUPPLY VOLTAGE..... 300 max volts
PLATE DISSIPATION...................... 1.0 max watt
GRIDS No. 2 & No. 4 DISSIPATION........ 1.0 max watt
TOTAL CATHODE CURRENT.................. 14 max ma
GRID No. 3 (CONTROL GRID) VOLTAGE:
Negative bias value................. 50 max volts
Positive bias value................. 0 max volts
PEAK HEATER-CATHODE VOLTAGE:
Heater negative w.r.t cathode....... 90 max volts
Heater positive w.r.t cathode....... 90 max volts
Characteristics - Separate Excitation: (1)
Plate Voltage 26.5 100 250 volts
Grids #2/#4 26.5 100 100 volts
Grid #3 -0.5 -1.5 -1.5 volts
Grid #1 (Oscillator Grid)
Resistor 20K 20K 20K ohms
Plate Resistance -- 0.5 1.0 megohm
Conversion Trans. 270 455 475 umhos
Conversion Trans.(2)
Approx -- 4 4 umhos
Conversion Trans.(3)
Approx 8 -- -- umhos
Plate Current 0.45 2.8 3.0 ma
Grids #2/#4 Current 1.6 8.0 7.8 ma
Grid #1 Current 0.1 0.5 0.5 ma
Total Cathode Current 2.15 11.3 11.3 ma
Characteristics of Oscillator Section: (4)
Plate Voltage 26.5 100 volts
Grids #2/#4 Voltage 26.5 100 volts
Grid #3 Voltage 0 0 volts
Grid #1 Voltage 0 0 volts
Amplification Factor - 22
Transconductance 4500 7200 umhos
Plate Current 5.5 27 ma
(1) The characteristics shown with separate excitation
correspond very closely with those obtained in a
self-excited oscillator circuit operating with
zero bias.
(2) with grid #3 bias of -30 volts
(3) with grid #3 bias of -6 volts
(4) Measured between grid #1 and grids #2/#4 connected
connected to plate (not oscillating).
The curves under type 6BE6 also
apply to the 26D6
Operations Characteristics Grid #3
Operations Characteristics Grid #1
