MIL-PRF-1-1655 Electron Tube, Receiving Type 6080Wc

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MIL-PRF-1/1655E

TABLE I. Test conditions - Continued.

NOTES:

1. Maximum grid-circuit resistance:

a. 1.0 megohm for cathode-bias operation.

b. 0.1 megohm for fixed-bias operation.

c. 0.1 megohm for combined fixed and cathode-bias operation.

See "Reduced pressure (altitude) rating" and altitude, maximum peak voltage in the basic

document.

3. A grid resistor of 0.1 megohm shall be added to each section; however, this resistor shall not be

used when a thyratron-type short indicator is employed.

4. Tie 1k to 2k; 1g to 2g; and 1a to 2a.

5. Envelope temperature (TE) requirements, when measured in accordance with the temperature

by conduction-band measurement (MIL-STD-1311, method 1226), will be satisfied if a tube

having bogey Ib (+5 percent) under normal test conditions, is determined to operate at or above

minimum specified temperature at any position in the life-test rack.

6. Test each unit separately.

7. Both units shall be operating.

8. This test to be performed at the conclusion of the holding period.

9. Rk bypassed with 1,000 �F capacitor.

10. Sweep-frequency vibration and fatigue-test procedure:

(a) This test shall be performed with an average acceleration level equal to the specified value

while being swept continuously during a time of approximately 1 minute through the

frequency range of 50 to 500 Hz and back to 50 Hz.

(b) The total excitation time for the test shall be not less than 3 minutes. The tube shall be

mounted in each of three planes X, Y, and Z for one-third of the total excitation time. In

each mounting plane, the tube shall experience at least one complete frequency sweep.

11. This test shall be conducted on the initial lot and thereafter on a lot approximately every 12

months. In the event of lot failure, the lot shall be rejected and the succeeding lots shall be

subjected to this test until a lot passes. When one lot has passed, the 12-month rule shall apply.