Eimac
3-500Z Amplifier
TYPICAL CATHODE DRIVEN (GROUNDED GRID) AMPLIFIER CIRCUIT FOR TWO 3-500Z TUBES
| C-1 | 250 pF, 4.5 kV | (Johnson 154-16) |
| C-2 | 1100 pF, 3 section | Jackson Bros LE-3-4595-380. (M Swedgal, 258 Broadway, N Y 10007) |
| C-3 | 500 pF, 2.5 kV mica | Sangamo H-5347 |
| C-4 | .001 uF, 5kV | Centralab 858S-1000 |
| C-5, C-6 | 500 pF, 10 kV | TV "door knob" capacitor |
| C-7 thru C-10 | .01uF, 600 V ceramic capacitor | (Centralab DD-103) |
| C-11, C-12 | .01 uF 1.6 kV ceramic capacitor | (Centralab DD16-103) |
| C-13, C-14 | .01 uF 600 V ceramic capacitor | (Centralab DD-103) |
| C-15 thru C-17 | .01 uF, 1 kV mica Capacitor | (Sangamo H-2210) |
| M-1 | 500 mAdc | |
| M-2 | 1000 mAdc | |
| RFC-1 | 50 uH | 14 bifilar turns #10 AWG enamelled wire wound on ferrite core. Q-1 material, 5 inches long. 1/2 inch diameter (Permag Central Corp., 1213 Estes Avenue, Elk Grove Village. IL 60007; Catalog #S-206-Q1). Notch core with file and break to length |
| RFC-2 | 100 uH. 1 Adc | 112 turns #26 AWG. spacewound wire diameter on 1" diam., 6" long ceramic from (Centralab X-3022H insulator). Series resonant with terminals shorted to 24.5 MHz |
| RFC-3 | 20 ohm, 50 Watt | wirewound resistor used as choke |
| RY-1 | VOX operated SPST relay. Energized when transmit | |
| PC-1. PC-2 | Three 100 ohm 2W carbon resistors in parallel. | Three turns #14 AWG 1/2" diam 3/4" long in parallel with resistors. (Equivalent: Ohmite P-300 reduced to 3 turns) |
| J-1, J-2 | Coaxial receptacle. UG-58A/U, for type N connector | |
| T-6 | 5 V at 30 Amp | Chicago-Stancor P-4648 |
| X-l, X-2 | EIMAC SK 410 socket and EIMAC SK-406 chimney | |
| B | Blower, 13 cubic feet at 0.2 inch back pressure | Use #3 impeller at 3100 rpm (Ripley 8472, Dayton 1C-180 or Redmond AK-2H-01AX) |
CATHODE CIRCUIT COMPONENTS:
| T-1 (10 meters) | 0.l5 uH. 4 turns #14 AWG on 1/2"-inch form, 1/2-long. Parallel capacitance: 200 pF, 1 kV silver mica capacitor. Resonant at 28.7 MHz. |
| T-2 (15 meters) | 0.l5 uH. same as T-1 Resonant at 21.3 MHz with 470 pF, 1 kV silver mica capacitor. |
| T-3 (20 meters) | 0.31 uH. 6 turns #14 AWG on 1/2-inch form, 1/2-inch long, slug tuned (National XR-50). Resonant at 14.2 MHz with 470 pF, 1 kV silver mica capacitor. |
| T-4 (40 meters) | 0.31 uH, same as T-3. Resonant at 7.2 MHz with 940 pF, (Two 470 pF 1 kV silver mica capacitors in parallel). |
| T-5 (80 meters) | 1.3 uH, 13 turns #18 AWG on 1/2-inch diameter form. 1/2-inch long, slug turned (National XR 50). Resonant at 3.8 MHz with 940 pF. same as T-4. |
PLATE CIRCUIT COMPONENTS (for plate potential of 2500 Vdc). RL=1725 Ohm :
The 10, 15 and 20 meter inductor (L1) may be 10 1/2 turns #8 AWG copper wire (or 3/16" tubing) 2" diam., 3" long. Ten meter tap is 5 1/4 turns from plate end: 15 meter tap is 7 1/4 turns from plate end. The 40-80 meter coil (L2) may be 16 turns #10 AWG 2 1/2" diam., 4" long. 40 meter tap is 8 turns from junction with coil L-1.
| S-2 | Single pole ceramic switch high voltage 30 ° index. Radio Switch Corp Model 86-A. |
| NOTE: | For additional data on plate circuit design, write for Amateur Service Bulletin #30, "Pi and Pi-L Networks for Linear Amplifier Service" |
| NOTE: | B- of power supply is floating and grounded only through plate meter M2 and the 50 ohm salety resistor. Cabinet of power supply should be grounded to amplifier cabinet as safety measure. |
ALL CREDIT TO THE USEFULNESS OF THIS (Formatting, data, etc..) goes to the original author: Kvindesland
Other references:
Eimac is available at http://www.eimac.com/.
3-500Z is now produced by Triton Services, Inc of Dunkirk, MD USA. They may be contacted at Triton Electron Technology Division, 3100 Charlotte Avenue, Easton, PA 18042. Phone - 610 252-7331, FAX - 610 258-6279.):
This page has been created in a text editor by a real programmer. [JW: Yep it was here also!]