Voltage Tetrode ·Tetrode
Directly heated subminiature electrometer tetrode for very-low-current measurement. Extremely low filament power and high input resistance suit sensitive instrumentation.
Directly heated subminiature electrometer tetrode for very-low-current measurement.
Subminiature 8-lead
General specifications
Properties common to every published source and operating point.
Electrical assignments shared by every tube using this base designation.
No verified pinout is recorded for this base designation.
1 physical section, each with unique specifications.
Section 1
Philips 4066 directly heated 1.25 V 13 mA subminiature electrometer tetrode for ultra-low-current measurements. Manufacturer explicit maximum anode voltage 10 V and maximum cathode current 300 µA (0.0003 A), filament operation range 1.1–1.5 V. Typical operating condition Va 4.5 V, Ia 20 µA, grid-1 current 250 µA, transconductance about 17 µA/V (0.000017 S) with an electrode-specific measurement arrangement. To avoid excessive drift energize filament before anode voltage, and keep glass envelope in protective sleeve until installed to avoid contamination; leakage-sensitive construction. Published operating points do not establish additional maximum ratings.
Source-dependent data
Each block preserves the test conditions and published values from one reference. Values from different sources are intentionally kept separate.
Data set 01
Published operating points and test conditions from this source.
HeaterOrFilamentVoltage
1.25 V
HeaterOrFilamentCurrent
13 mA
Plate Voltage
4.5 V
Electrometer
Plate Current
20 uA
Electrometer
Grid1 Current
250 uA
Electrometer
Data set 02
Published operating points and test conditions from this source.
Heating : direct by D.C. Ve
1.25 V
Heating : direct by D.C. Ve = 1,25 V
Va
4.5 v
Va = 4,5 v
Ia
20 uA
Ia = 20 uA
Vg2 = -3,2 -2,0
-4.5 v
Vg2 = -3,2 -2,0 -4,5 v
2)"Crossover point”(measured at Va
4.5 V
2)"Crossover point”(measured at Va=4,5 V, Ig1=250 uA) is
this point, Vg2 is at least
0.5 V
this point, Vg2 is at least 0,5 V less negative than
its value at §a
20 uA
its value at §a= 20 uA.
"Point de croissement" (mesurée 4 Vp
4.5 V
"Point de croissement" (mesurée 4 Vp=4,5 V,Ig1=250 p4)
é%ant de
0.5 V
é%ant de 0,5 V au moins.
"Ubergangspunkt"(gemessen bei Vg
4.5 V
"Ubergangspunkt"(gemessen bei Vg= 4,5 V, Ig1= 250 pid),
dndert. In diesem Punkt ist Vg2 mindestens
0.5 V
dndert. In diesem Punkt ist Vg2 mindestens 0,5 V we-
niger negatif als Vg2 bei Ig
20 uA
niger negatif als Vg2 bei Ig = 20 uA.
Ig1
250 uA
Ig1 = 250 uA
Vg1 = 3,0 2,0
4 v
Vg1 = 3,0 2,0 4,0 v
JnCrossover point"(measured at Va
4.5 V
JnCrossover point"(measured at Va=4,5 V, Ig1=250 pA) is
this point, Vgo is at least
0.5 V
this point, Vgo is at least 0,5 V less negative than
its value at Iag
20 uA
its value at Iag= 20 uA.
"Point de croissement® (mesurfe & Vy
4.5 V
"Point de croissement® (mesurfe & Vy=4,5 V,Ig1=250 uA)
Vg2 est moins nbgative que Vgo g I5
20 uA
Vg2 est moins nbgative que Vgo g I5=20 uA,la différence
"{bergangspunkt"(gemessen bei Vo
4.5 V
"{bergangspunkt"(gemessen bei Vo= 4,5 V, Igq= 250 ud)},
tindert. In diesem Punkt ist Vg2 mindestens
0.5 V
tindert. In diesem Punkt ist Vg2 mindestens 0,5 V we-
niger negatif als Vgp bei Ig
20 uA
niger negatif als Vgp bei Ig = 20 uA.
i) Vg
4.5 V
i) Vg = 4,5V H--—- Iy (A)