1、 MIL-PRF-1/1506E 4 August 2009 _ SUPERSEDING MIL-PRF-1/1506D 18 June 1999 PERFORMANCE SPECIFICATION SHEET ELECTRON TUBE, POWER TYPE 8245 This specification is approved for use by all Departments and Agencies of the Department of Defense. The requirements for acquiring the electron tube described her
2、ein shall consist of this document and the latest issue of MIL-PRF-1. DESCRIPTION: Tetrode, ceramic-metal. See figure 1. Mounting position: Any. Weight: 4 ounces (113.4 grams) nominal. ABSOLUTE RATINGS: F (CW) = 500 MHz, F (pulsed) = 1,500 MHz. Parameter: Ef eb Eb ec1 Ec1 ec2 Ec2 Ib ib ik Unit: V ac
3、 1/ kv 2/ V dc v 2/ V dc kv 2/ V dc mA dc a 2/ a Maximum: Class C Telep: 6.0 5% - 1,500 - -250 - 300 200 - - Class C Teleg: 6.0 5% - 2,000 - -250 - 300 250 - - Class AB: 6.0 5% - 2,000 - - - 400 250 - - Class C pulsed: 6.0 5% 7.0 - -500 - 1.5 - - 6.0 7.0 Test conditions: 6.0 - 1,000 - Adj - 300 150
4、- - ABSOLUTE RATINGS: F (CW) = 500 MHz, F (pulsed) = 1,500 MHz. Parameter: Pg1 Pg2 Pp Pi tp tk T(anode core and seal) Cooling Unit: W W W W s 2/ s (min) C - 3/ Maximum: Class C Telep: 2 12 165 300 - 30 250 - Class C Teleg: 2 12 250 500 - 30 250 - Class AB: 2 12 250 500 - 30 250 - Class C pulsed: 2 1
5、2 250 500 5.0 30 250 - Test conditions: - - - - - 120 - 4/ _ GENERAL: Qualification: Not required. AMSC N/A FSC 5960 INCH-POUND Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-1/1506E 2 TABLE I. Testing and inspection. Inspection Method Notes
6、Conditions Symbol Limits Unit MIL-STD-1311 Min Max Conformance inspection, part 1 Heater current 1301 5/ If 2.30 3.00 A ac Electrode voltage (grid) 1261 Ec1 -32 -45 V dc Electrode current (screen) 1256 Ic2 -5.0 +3.0 mA dc Total grid current 1266 6/ Eb = 2,000 V dc; Ec1/Ib = 125 mA dc Ic1 - -15 A dc
7、Primary grid emission (control) 1266 Ic1 = 70 mA dc t = 15; anode and g2 floating Isg1 - -25 A dc Primary grid emission (screen) 1266 Ec1 = 0; t = 15; Ic2 = 100 mA dc; anode floatingIsg2 - -250 A dc Pulse emission (1) 2212 7/ Eb = Ec2 = 250 V dc; Ec1 = -100 V dc; prr = 11 1; tp = 4,500 s (min); ec1/
8、ik = 1.5 a; Ef = 5.4 V ac ik - 200 ma Current division (long pulse, method A) 1372 Eb = Ec2 = 250 V dc; Ec1 = -100 V dc; prr = 11 1; tp = 4,500 s (min); ec1/ib = 1.0 a egk ic ic2 8.0 - - 18.0 200 260 v ma ma Conformance inspection, part 2 RF useful power output 2214 8/ Class C amplifer; F = 470 to 5
9、00 MHz; Eb = 2,000 V dc; Ec1 = -90 V dc; Ec2 = 250 to 300 V dc; Ic1 = 25 mA dc (max); Eg1/Ib = 250 mA dc; Ef = 5.50 V ac Po 225 - W (useful) Pulse emission (2) 2212 7/ Eb = Ec2 = 250 V dc; Ec1 = -100 V dc; prr = 11 1; tp = 4,500 s (min); ec1/ik =1.5 aik - 100 ma See footnotes at end of table. Provid
10、ed by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-1/1506E 3 TABLE I. Testing and inspection - Continued. Inspection Method Notes Conditions SymbolLimits UnitMIL-STD-1311 Min Max Conformance inspection, part 2 Continued Direct-interelectrode capacitan
11、ce 1331 Grounded grid Cpk Cin Cout- 14.5 4.2 0.01 19.0 5.2 pF pF pF Direct-interelectrode capacitance 1331 Grounded cathode Cgp Cin Cout- 25.0 4.2 0.05 29.0 5.2 pF pF pF Conformance inspection, part 3 Low-frequency vibration 1031 No voltages - - - - Shock, specified pulse 1042 No voltages; 15 G peak
12、 (min); D = 11 2 ms; half-sine wave - - - - Life test (1) - Group C; Class C amplifier; F = 470 to 500 MHz Eb = 2,000 V dc; Ec1 = -90 V dc; Ec2 = 250 to 300 V dc; Ic1 = 25 mA dc (max); Eg1/Ib = 250 mA dc; Ef = 5.50 V act 500 - hours Life-test (1) end points: Pulse emission (2) - 2212 7/ Eb = Ec2 = 2
13、50 V dc; Ec1 = -100 V dc; prr = 11 1; tp = 4,500 s (min); ec1/ik = 1.5 aik - 100 ma Primary grid emission (control) 1266 Ic1 = 70 mA dc; t = 15; anode and g2 floatingIsg1 - -100 A dc Primary gird emission (screen) 1266 Ec1 = 0; t = 15; Ic2 = 100 mA dc; anode floatingIsg2 - -250 A dc Life test (2) -
14、Group C; Ec1 = Ec2 = Eb = 0; Ef = 6.6 V act 500 - hours Life-test (2) end point: Interelement leakage resistance, cold - 1366 Rs = 2.5 Meg; supply voltage = E = 100 V dc; g1 negative E = 500 V dc; g2 positive E = 500 V dc; g1 negativeRg1k Rg2K Rg1g210 10 10 - - - Meg Meg MegPulse power output - 9/ e
15、b = 7.0 kv; ec2 = 1.2 kv; ib = 6.0 a; tp = 5 s; prr = 1,000; F = 1,200 50 MHz po 17 - kw See footnotes at top of next page. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-1/1506E 4 TABLE I. Testing and inspection - Continued. 1/ At frequenci
16、es above approximately 300 MHz, it may be necessary to reduce heater voltage to compensate for rf transit-time heating of the cathode after dynamic operation of the tube has started. This back heating is a function of frequency, grid current, grid bias, anode current, duty cycle, and circuit design
17、and adjustment. There is an optimum heater voltage which will maintain the cathode at the correct operating temperature for any particular set of operating conditions. A maximum variation of 5 percent from optimum shall be maintained. For straight-through, class C CW amplifier operation, the followi
18、ng heater operation voltages are indicated: Frequency (MHz) Ef (V ac) 301 to 400 5.75 401 to 500 5.50 2/ With a pulse repetition rate (prr) of 1,000 or less and a pulse duration (tp) of 5 s or less, peak anode current (ib) shall be limited to 6.0 amperes. For pulses of longer duration or higher repe
19、tition rates, peak anode current shall be reduced in accordance with the data shown on figure 2, and pulse anode voltage, screen voltage, and grid voltage shall be reduced in accordance with the data shown on figure 3. 3/ Forced-air cooling shall be provided for the base and anode. The maximum seal
20、and anode core temperature rating shall not be exceeded. At an anode dissipation of 250 watts and with an incoming air temperature of 25C maximum at sea level, a minimum airflow of 3.8 cfm shall pass through the anode cooler. With no voltages applied to the tube, the static pressure drop across the
21、anode cooler with an airflow of 3.8 cfm (at 25C at sea level) is approximately .15 inch of water. The pressure drop varies with the amount of escaping air and with the shape and construction of the air director. This airflow requirement applies at bias voltages less than -100 volts and at frequencie
22、s less than 500 MHz (CW) and 1,500 MHz (pulsed). Air cooling on the tube shall be increased with increased negative grid bias, increased incoming air temperature, or increased frequency of operation. The stem shall be cooled either by a portion of the anode air or by a separate air supply. Airflow s
23、hall be applied before or simultaneously with the electrode voltages and may be removed simultaneously with them. In cases where long life and reliable operation are factors, operation with cooling in excess of minimum requirements is recommended. 4/ In all electrical tests involving application of
24、heater voltage, forced-air cooling is permitted at the rate of 4.0 cfm maximum for the base and anode. A separate source may be used for the base and anode but neither source shall exceed 4.0 cfm. The cooling air shall not have a temperature less than 20C nor an absolute pressure greater than 32 inc
25、hes Hg. 5/ The acceptance level for each test in conformance inspection, part 1, shall be 0.65, inspection level II. 6/ This test shall be the first test performed at the conclusion of the holding period. 7/ The input wave shape shall have a tr and a tf of 25 s maximum each, and the slope of the top
26、 of the pulse may be not greater than 0.5 percent with a ripple not to exceed 0.1 percent. 8/ Use cavity and circuit as shown on Drawing 224-JAN. 9/ This specification sheet uses accept on zero defect sampling plan in accordance with MIL-PRF-1, table III. Provided by IHSNot for ResaleNo reproduction
27、 or networking permitted without license from IHS-,-,-MIL-PRF-1/1506E 5 FIGURE 1. Outline drawing of electron tube type 8245. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-1/1506E 6 Dimensions Ltr Inches Millimeters Min Max Min Max Conforma
28、nce inspection, part 2 A - 2.813 - 71.45 B 1.610 1.640 40.89 41.66 D 1.410 1.440 35.81 36.58 E .587 .597 14.91 15.16 F .317 .327 8.05 8.31 G .088 .098 2.24 2.49 Conformance inspection, part 3 (see note) C - 1.406 - 35.71 H - .358 - 9.09 J .710 .790 18.03 20.07 K .740 .820 18.80 20.83 L .187 - 4.75 -
29、 M .500 .580 12.70 14.73 N .235 .265 5.97 6.73 P .032 .062 0.81 1.57 T .344 - 8.74 - U .406 - 10.31 - V .468 - 11.89 - W .559 .573 14.20 14.55 X .240 - 6.10 - Reference dimensions R .020 0.51 S .125 3.18 NOTE: Dimensions shall be checked yearly. A regular double sampling plan shall be used, with the
30、 first sample of three tubes with an acceptance number of zero, and a second sample of three tubes with an acceptance number of one. In the event of failure, the test will be made as a part of conformance inspection, part 2, acceptance level of 6.5, inspection level S3. The regular yearly double sam
31、pling plan may be reinstated after three consecutive samples have been accepted. FIGURE 1. Outline drawing of electron tube type 8245 - Continued. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-1/1506E 7 NOTES: 1. Solid lines represent const
32、ant repetition rates; dashed lines represent constant duty factors. 2. Do not extrapolate above or to the left of bold lines. FIGURE 2. Anode current versus pulse duration. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-1/1506E 8 FIGURE 3. D
33、erating chart: pulse anode voltage, screen voltage, and grid voltage versus pulse duration (tp). Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-1/1506E 9 Referenced documents. In addition to MIL-PRF-1, this document references the following:
34、 MIL-STD-1311 Drawing 224-JAN The margins of this specification are marked with vertical lines to indicate where changes from the previous issue were made. This was done as a convenience only and the Government assumes no liability whatsoever for any inaccuracies in these notations. Bidders and cont
35、ractors are cautioned to evaluate the requirements of this document based on the entire content irrespective of the marginal notations and relationship to the last previous issue. Custodian: Preparing activity: Army - CR DLA - CC Navy - EC Air Force - 11 (Project 5960-2009-025) Review activities: Ar
36、my - CR4 Navy - AS, CG, MC, OS, SH Air Force - 99 NOTE: The activities listed above were interested in this document as of the date of this document. Since organizations and responsibilities can change, you should verify the currency of the information above using the ASSIST Online database at http:/assist.daps.dla.mil/. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
