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CV1949 argon thyratron / RF noise source

Size The valve measures 53x17mm overall and has a B7G base.


Heater voltage 6.3V
Heater current 250mA
Max DC supply anode voltage 250V
Peak forward anode voltage 350V
Peak inverse anode voltage 350V
Max DC grid voltage -150V
Peak DC anode current 110mA
Max DC anode current 25mA
Max heater-cathode voltage -110V
Max cathode heating time 30 secs
Max duty cycle 0.75%
Max ambient operating temperature -55 to +90 C


Pin Function
1 Grid
2 n/c
3 Heater
4 Heater
5 Cathode
6 n/c
7 Anode

Although this thyratron can be used normally, it is more famous for its use as an RF noise source. With the valve mounted in a magnetic field arranged such that the electron beam is deflected towards the top of the valve - with magnetic north at pin 7 - the following test data is specified:

Frequency, MHz Min. noise voltage, µV, RMS
0.1 10,000
0.2 14,000
0.5 25,000
1.0 22,000
2.0 7,000
5.0 500
10.0 70