MIL-PRF-1/1636C
TABLE I. Testing and inspection - Continued.
Limits
Inspection
Method
Conditions
Symbol
Min
Max
Unit
Conformance inspection,
part 3 - Continued
---
Sweep-frequency vibration
and shock end points:
v
150
egy
----
3246
Operation (1)
V dc
300
----
3247
Ebb
DC anode voltage for
conduction
0.005
----
3261
Time jitter
tj
µs
egy
----
150
v
3246
Operation at elevated
TA = 150°C;
ambient temperature 4/
t = 5 hours
9/ 15/
1/ Instantaneous starting is permissible. The maximum permissible instantaneously applied epy is 8.0 kv and
shall not be attained in less than 0.04 seconds. The epy may then be raised to full rating.
2/ In pulse operation, the peak inverse voltage, exclusive of a spike of 0.05 µs maximum duration, shall not
exceed 2.0 kv during the first 25 µs following the anode pulse.
3/ The driver pulse, measured at tube socket with thyratron grid disconnected shall have the following
characteristics: 175 volts minimum; 600 volts maximum; tr = 0.35 µs maximum; tp = 2.0 µs minimum,
impedance of drive circuit Zg = 1,500-ohms maximum. At -55°C, 250 V minimum shall be required.
4/ This test shall be performed during the initial production and once each succeeding 12-calendar months in
which there is production. An accept on zero defect sampling plan shall be used, with sample of three tubes
with acceptance on zero defects. In the event of failure, the test will be made as a part of conformance
inspection, part 2, with an acceptance level of 6.5 (see 16/). The regular "12-calendar month" sampling plan
shall be reinstated after three consecutive samples have been accepted.
5/ The tube is capable of operation of over 50,000 pps within the limitations of the Pb and Ib current ratings. W ith
9
a saturable reactor, Pb equal to 4 x 10 is permissible for certain applications.
6/ It may be desirable to employ forced-air cooling under conditions of high Pb number operations. A cooling
airblast of 5 cfm may be directed into the anode cup.
7/ Appreciably less jitter than 0.005 µs can be realized if the anode voltage is 3 kv or more, grid drive amplitude is
near the maximum and grid drive impedance is near minimum.
8/ There shall be no pronounced resonance in the range from 0 to 2,000 Hz.
9/ The circuit constants shall be chosen under resonant charging conditions so that: epy = 14 kv; ib = 150 a
minimum; dik/dt = 1,500 a/µs minimum; tp = 1.0 + 10 percent; prr = 1,000 minimum; Rg1 = 30,000 ohms. Grid
pulse characteristics shall be: tr = 0.35 µs minimum; tp = 2.0 µs maximum, and Zg = 500-ohms minimum.
10/ The tube shall operate satisfactorily on push-button starting within three attempts when the anode voltage (epy) is
applied to the TUT in such a manner as to rise from 0 to 8 kv minimum within 0.03 seconds. (The filter in the
rectifier shall be designed so that the epy reaches at least 4 kv within 0.015 second.)
11/ This test shall be conducted within 60 seconds of the operation (1) test.
12/ The tube shall operate continuously for 10 minutes.
3