MIL-PRF-1/1702C
TABLE I. Testing and inspection - Continued.
16/
The TUT shall be mounted in a socket in accordance with Drawing 276-JAN (21/) and vibrated with simple harmonic motion. The
peak acceleration over the frequency range shall be within ± 20 percent of the reference acceleration at 100 Hz. The frequency
shall vary from 55 Hz to 500 Hz and return to 55 Hz with approximately logarithmic progression and shall require 4 minutes
minimum, 6 minutes maximum to traverse the range. Each tube shall be vibrated for 30 minutes in each direction X and Z except
that if the cumulative results of test on 50 or more tubes of a construction show that more than 75 percent of the tubes have higher
output voltages in one position, subsequent measurements need to be taken only in the position giving the higher reading. The
value of the alternating voltages Ep, produced across the resistor Rp as a result of vibration, shall be measured with a suitable
device. This device shall have an appropriate voltage range and shall have the ability to measure with an error of less than 10
percent the rms value of a sine wave of voltage at all frequencies from 20 to 20,000 Hz. The value of the vibrational output Ep shall
not exceed the limit specified herein at any point in the sweep-frequency range during the last complete cycle of the cycling
vibration.
17/
The torque test shall be performed as follows:
a.
The tube shall be held securely at the cathode connection. A force of 5 pounds shall be applied to the heater cup without
perceptible shock. This test may be made by applying the force at right angles to the inside of the cup at a point 7/64-inch
(2.76 mm) ± 1/64-inch (0.41 mm) from the cathode end of the tube. An approved equivalent method may be used. The
heater cup shall not loosen or short circuit on the cathode connection. This part of the test shall not be required if the space
between the heater cup and the cathode sleeve is completely filled with insulating material.
b.
A torque of 15 inch-pounds shall be applied between anode and cathode without shock.
c.
A torque of 40 inch-pounds shall be applied between anode and grid without shock.
18/
Voltage shall be applied between the anode and grid. No other voltages shall be applied.
19/
At zero hours, establish the drive conditions necessary to obtain 2.0 amperes peak anode current with an anode voltage of 1,000 V
dc and a bias voltage of -40 V dc and Ef = 6.0 V. The pulse width of the modulator shall be 2 µs (minimum) and the duty cycle
shall be 0.0025 maximum. W ith the drive level determined at zero hours, check the anode current at the end of life. The maximum
allowable drop in anode current (Ćib) is as specified.
20/
Revision letters are not used to denote changes due to the extensiveness of the changes.
21/
Contact preparing activity if help is needed locating JAN drawings.
5
For Parts Inquires call Parts Hangar, Inc (727) 493-0744
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business