1、 MIL-PRF-1/1457F 27 July 2009 SUPERSEDING MIL-PRF-1/1457E 25 June 1999 PERFORMANCE SPECIFICATION SHEET ELECTRON TUBE, POWER TYPE 7843 This specification is approved for use by all Departments and Agencies of the Department of Defense. The requirements for acquiring the electron tube described herein
2、 shall consist of this document and the latest issue of MIL-PRF-1. DESCRIPTION: Tetrode, UHF, ceramic-metal. See figure 1. Mounting position: Any. Weight: 2 ounces (56.7 grams) nominal. ABSOLUTE RATINGS: F = 400 MHz Parameter: Ef Eb Ec1 Ec2 Ib Ic1 Pg1 Pg2 Pp Unit: V 1/ V dc V dc V dc mA dc mA dc W W
3、 W Maximum: AB audio: AB SSBSC: C telep: C teleg: 26.5 10 % 26.5 10 % 26.5 10 % 26.5 10 % 1,000 1,000 800 1,000 - - -100 -100 300 300 300 300 180 250 2/ 150 180 30 30 30 30 1.0 1.0 1.0 1.0 7.0 7.0 4.6 7.0 115 115 75 115 Test conditions: 26.5 1,000 Adj 300 - - - - - ABSOLUTE RATINGS: F = 400 MHz Para
4、meter: Pi T(seal) tk Cooling Barometric pressure, reduced Unit: W C 3/ sec (min) - 4/ mmHg Maximum: AB audio: AB SSBSC: C telep: C teleg: 180 180 120 180 250 250 250 250 60 60 60 60 - - - - 141.2 141.2 141.2 141.2 Test conditions: - - 60 5/ - See footnotes at end of table I. _ GENERAL: Qualification
5、 - Required. AMSC N/A FSC 5960 INCH-POUND Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-1/1457F 2 TABLE I. Testing and inspection. Inspection Method Notes Condition Symbol Limits Unit MIL-STD-1311 Min Max Conformance inspection, part 1 Tota
6、l grid current 1266 6/ 7/ 8/ Ec1/Ib = 115 mA dc Ic1 - -8.0 A dc Electrode current (screen) 1256 - Ec1/Ib = 115 mA dc Ic2 -4.7 2.0 mA dc Electrode voltage (1) (grid) 1261 - Ec1/Ib = 115 mA dc Ec1 -9.0 -18.0 V dc Electrode voltage (2) (grid) 1261 - Ec1/Ib = 1.0 mA dc Eco - -48 V dc Pulsing emission 12
7、31 9/ etd/ik = 10 a etd - 300 v Zero-bias anode current - 10/ Ef = 21.5 V; Eb = 400 V dc; Ec2 = 200 V dc; Ec1 = 0; tk = 120; t = 60 (max) Ibo 170 - mA dc Heater current 1301 - If 0.48 0.60 A Conformance inspection, part 2 Primary grid emission (control) 1266 - Eg1/g1 input = 2W; t = 30; anode and g2
8、 grounded Isg1 - -2.0 A dc Primary grid emission (screen) 1266 - Eg2/g2 input = 7.0 W; t = 30; anode and g1 grounded Isg2 - -3.0 A dc Interelement leakage resistance, cold 1366 11/ Supply voltage = 200 V dc R 1.0 - Meg Power output 2214 12/ F = 400 20 MHz; Ib = 180 mA dc (max); Ic1 = 30 mA dc (max);
9、 t = 120; Pd = 3.3 W (max); Ef = 24.0 V Po 85 - W Direct-interelectrode capacitance 1331 - Use capacitance fixture in accordance with 289-JAN Cg1k Cg1g2 Cg2p Cg1p Cpk Cg2k 11.0 15.0 4.2 - - 0.20 15.0 20.0 5.2 0.065 0.013 0.45 pF pF pF pF pF pF Power oscillation 1236 - F = 15 MHz; Ef = 21.5 V; Eb = 8
10、50 V dc; Ec2 = 300 V dc (max); Ib = 150 mA dc; Rg1 = 4,000 ohms (max); Ic1 = 30 mA dc; t = 120 Po 80 - W (useful) Current division, long pulse (method A) 1372 - Eb = 350 V dc; Ec1 = -100 V dc; egk/ib = 0.6 a; prr = 10 to 12; tp = 4,500 to 5,000 s egk ic1 ic2 -3.0 0 10 +17 130 70 v ma ma See footnote
11、s at end of table.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-1/1457F 3 TABLE I. Testing and inspection - Continued. Inspection Method Notes Condition Symbol Limits Unit MIL-STD-1311 Min Max Conformance inspection, part 3 Life test - 8/ 1
12、2/ Group C; Ef = 26.0 V; Ib = 180 mA dc; F = 400 20 MHz; Ic1 = 30 mA dc (max); Ec1 = value obtained for Eco in electrode voltage (2) grid test in accordance with part 1 herein; t = 500 hours - - - - Life-test end points: Pulsing emission Primary grid emission (control) Primary grid emission (screen)
13、 Power output Power oscillation - 1231 1266 1266 2214 1236 - - - - - etd/ik = 7.5 a etd Isg1 Isg2 Po Po - - - 75 65 400 -4.0 -4.0 - - v A dc A dc W W (useful) Heater-cycling life 1506 - Group C; Ef = 35.0 V; accelerated heater-cycling 2.5 minutes “on“, 5 minutes “off“ - 384 - Cycles Heater-cycling l
14、ife-test end point: Heater current - 1301 - If 0.4 0.7 A Low-frequency vibration 1031 13/ Ebb = 300 V dc; Ec2 = 250 V dc; Ec1/Ib = 10 mA dc; Rp = 2,000 ohms Ep - 300 mV ac High-frequency vibration 1031 13/ No voltages - - - - Shock, specified pulse 1042 13/ 15 G, 11 ms, half-sine; no voltages - - -
15、- Vibration and shock-test end points: Total grid current Electrode voltage (1) (grid) - 1266 1261 8/ - Ec1/Ib = 115 mA dc Ec1/Ib = 115 mA dc Ic1 Ec1 - -9.0 -8.0 -18.0 A dc V dc Barometric pressure, reduced 1002 13/ Pressure = 141.2 mmHg; voltage = 1,300 V dc applied between p and k, with k, g1, and
16、 g2 tied together. - - - - See footnotes at end of table.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-1/1457F 4 TABLE I. Testing and inspection - Continued. 1/ Because the cathode is subjected to considerable back bombardment as the freque
17、ncy is increased, with resultant increase in temperature, the heater voltage shall be decreased depending on operating conditions and frequency to prevent overheating the cathode and resultant short life. 2/ The maximum dc anode current at the peak of the current curve is 250 mA dc for a signal havi
18、ng a minimum peak-to-average power ratio of 2.0. The maximum rating for a signal having a minimum peak-to-average power ratio of less than 2.0, such as is obtained in single-tone operation, is 180 mA dc. During short periods of circuit adjustment under single-tone conditions, the average anode curre
19、nt may also reach the level of 250 mA dc. 3/ Unless otherwise specified, sufficient cooling shall be supplied to maintain anode core and seal temperatures below the maximum rating. 4/ In all applications, sufficient cooling shall be supplied to make effective the requirements in 3/ above, including
20、sufficient conduction cooling for the base contacts. In applications where reliable performance and long life are factors, operation at temperatures below the absolute maximum rating is normally beneficial. 5/ Unless otherwise specified in the test conditions, in all electrical tests, involving appl
21、ication of heater voltage, a dummy radiator or heat-sink may be attached to the anode of the tube under test (TUT). When this is used, forced-air cooling of the anode is permissible in order to maintain the anode core temperature below 250C. Base seals may be cooled by conduction, or by other means
22、where required, in order to maintain seal temperatures below the maximum ratings. 6/ The acceptance level for each test listed under conformance inspection, part 1, shall be 0.65, inspection level II. 7/ This test shall be the first test performed after the specified holding period. 8/ Cooling shall
23、 be set up to maintain the tube temperature at the hottest point on the tube envelope at 225C 25C. (This setup should be permanent and needs to be verified only as often as required to maintain equipment accuracy.) 9/ With anode, grid 1, and grid 2 tied together, apply a pulse voltage source between
24、 anode and cathode. Adjust the pulse amplitude until the specified peak cathode current is obtained. Test shall be made at the end of 1 minute or when stability is reached, whichever occurs first. The pulse voltage shall meet the following requirements: a. Pulse duration: 2 s. b. Pulse repetition ra
25、te: 60 pps. c. Duty factor: 0.00012. 10/ Before subjection to this test, the tube shall be cooled to room ambient temperature for 30 minutes minimum, then preheated at Ef = 21.5 volts for 120 seconds prior to the application of other voltages. During this test, grid No. 1 shall be connected to the c
26、athode. 11/ Before subjection to this test, the tube shall be cooled to room ambient temperature for 30 minutes. Using the test circuit shown on the figure of method 1366, measure the resistance, in both directions, between any two adjacent electrodes (except across the heater terminals). If the res
27、istance value is below that required, repeat this test after a 10-minute interval. If the tube fails again, the tube shall be rejected. 12/ Tube shall be tested in a grid-driven amplifier circuit. Adjust Ec1 bias supply and tune circuit for maximum useful power output. The specified driver power (Pd
28、) output shall be measured with a Bird Thru-line Wattmeter, or equivalent. Driving power output = forward power minus reflected power. Grid voltage supply shall have an effective impedance of 500 ohms maximum. 13/ This test shall be performed during the initial production and once each succeeding 12
29、-calendar months in which there is production. A regular double sampling plan shall be used, with the first sample of three tubes with an acceptance number of zero, and a second sample of three tubes with a combined acceptance number of one. In the event of failure, the test will be made as a part o
30、f conformance inspection, part 2, code level D, with an acceptance level of 6.5. The regular “12-calendar month“ double sampling plan shall be reinstated after three consecutive samples have been accepted. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-
31、,-,-MIL-PRF-1/1457F 5 FIGURE 1. Outline drawing of electron tube type 7843. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-1/1457F 6 Dimensions Ltr Inches Millimeters Notes Min Max Min Max Conformance inspection, part 1 Gauge check 1 Conform
32、ance inspection, part 2 B 1.805 1.955 45.85 49.66 D .895 .905 22.73 22.99 Conformance inspection, part 3 11 C .990 1.080 25.15 27.43 E .165 - 4.19 - F .340 .410 8.64 10.41 G .140 - 3.56 - H .150 .200 3.81 5.08 J .120 - 3.05 - 2 K .095 - 2.41 - 2 L .100 - 2.54 - 4 M - .050 - 1.27 N 1.085 - 27.56 - 5
33、P .985 - 25.02 - 6 Q .735 - 18.67 - 7 R .480 - 12.12 - 8 S - .072 - 1.83 T - .260 - 6.60 U .054 - 1.37 - 4 W .780 - 19.81 - Y .060 - 1.52 - 3 Z .090 - 2.29 - 3 AA - - - - 9 BB - - - - 10 CC .600 - 15.24 - FIGURE 1. Outline drawing of electron tube type 7843 - Continued.Provided by IHSNot for ResaleN
34、o reproduction or networking permitted without license from IHS-,-,-MIL-PRF-1/1457F 7 NOTE: The edge of the grid No. 1, No. 2, and No. 3 terminal shall be flush with or extend beyond the surface “AA“, “BB“, or “CC“ on the gauge. FIGURE 1. Outline drawing of electron tube type 7843 - Continued. Provi
35、ded by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-1/1457F 8 Dimensions Ltr Inches Millimeters Min Max Min Max Gauge No. 1 D - 2.50 - 63.5 E .121 .123 3.07 3.12 F - .062 DIA - 1.57 DIA G .096 DIA .097 DIA 2.44 DIA 2.46 DIA Gauge No. 2 H - 2.50 - 63.5
36、 J .061 .063 1.55 1.60 K - .062 DIA - 1.57 DIA L .091 DIA .092 DIA 2.31 DIA 2.34 DIA Gauge No. 3 M - 2.50 - 63.5 N .102 .104 2.59 2.64 P .110 DIA .140 DIA 2.79 DIA 3.56 DIA R .0545 .0555 1.384 1.410 S .082 DIA .088 DIA 2.08 DIA 2.23 DIA T .2445 DIA .2450 DIA 6.210 DIA 6.223 DIA Gauge No. 4 U - 1.315
37、 (H0) - 33.40 (H0) V - .002 - 0.05 W .951 .953 24.15 24.21 X - 1.956 - 49.68 Y - 1.120 (H1) DIA - 28.45 (H1) DIA Z - 1.020 (H2) DIA - 25.91 (H2) DIA AA - .765 (H3) DIA - 19.43 (H3) DIA BB - .520 (H4) DIA - 13.21 (H4) DIA CC .238 (P) DIA - 6.05 (P) DIA - DD - .072 (H5) DIA - 1.83 (H5) DIA EE .098 .10
38、0 FF - .305 - 7.75 GG - .960 - 24.38 HH - .600 - 15.24 JJ - .130 - 3.30 FIGURE 1. Outline drawing of electron tube type 7843 - Continued. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-1/1457F 9 NOTES: 1. With the cylindrical surfaces of the
39、 anode cap, anode terminal, screen grid terminal, control grid terminal, heater cathode terminal and heater terminal clean, smooth, and free of burrs, each tube will enter the gauge No. 4 to determine out of roundness, concentricity, and oversize. Gauge ring shall enter between gauge No. 4 and anode
40、 cap of tube until insert rests on anode flange of tube. The axes of the gauge ring I. D. and gauge ring O. D. are coincident within .001 inch. The axes of cylindrical holes H0through H5and the axis of post P shall be concentric within .001 inch. Proper seating is determined by failure of a .010 inc
41、h thickness gauge .125 inch wide to enter between heater cathode terminal and bottom surface of H4. A slot is provided to permit this measurement to be made. The acceptance level for dimensions listed under conformance inspection, part 1 shall be 1.0, inspection level II. 2. This dimension to be che
42、cked by gauge No. 1 entering this area. The edge of the grid No. 1 terminal shall be flush with or extend beyond the surface “AA“ on the gauge. 3. This dimension to be checked by gauge No. 2 entering this area. The edge of grid No. 2 terminal shall be flush with or extend beyond the surface “CC“ on
43、the gauge. 4. This dimension to be checked by gauge No. 3 entering this area. The edge of the heater terminal shall be flush with or extend beyond the surface “BB“ on the gauge. 5. Dimension “N“ applies over length “E“ only. 6. Dimension “P“ applies over length “G“ only. 7. Dimension “Q“ applies ove
44、r length “F“ minus “H“ only. 8. Dimension “R“ applies over length “H“ only. 9. On any one tube, this dimension shall never be greater than “N“. 10. On any one tube, this dimension shall never be greater than “P“. 11. Perform test(s) every six months, with sampling as follows: n1 = 4 c1 = 0 where c2
45、represents the total failures for the n2 = 4 c2 = 1; first and second samples combined. In case of failure, the failing dimension(s) shall become conformance inspection, part 2, acceptance level 6.5, inspection level S3 for three successful successive submissions, at which time the testing may rever
46、t to the twice-yearly basis. FIGURE 1. Outline drawing of electron tube type 7843 - Continued.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-1/1457F 10 Referenced documents. In addition to MIL-PRF-1, this document references the following: M
47、IL-STD-1311 Drawing 289-JAN Marginal notations are not used in this revision to identify changes with respect to the previous issue due to the extent of the changes. Custodians: Preparing activity: Army - CR DLA - CC Navy - EC Air Force - 85 (Project 5960-2009-022) DLA - CC Review activities: Army - AR Navy - AS, CG, MC, OS, SH Air Force - 19, 99 NOTE: The activities listed above were interested in this document as of the date of this document. Since organizations and re
