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"My Version of a 3cx1500/a7
8877 144mhz W6PO amp"
(I am running a little over 4kv on the plate. Amp will do over 2kw out)
Give the page time
to load. There are several Pic's on this page to load.
To see what it looked like before + to see the HV supply click here.
Look here for where to get the parts for this. Thanks Paul WD7S
Look here for where to get the
Jennings RJ1A or Kilovac HC-1 relays. Thanks Allen
(either the Jennings or Kilovac will work fine)
Some things the new W6PO has that a stock W6PO does not have. Triode Control Board
1. ADJUSTABLE WARM-UP TIMER; HOLDS OFF HV AND
2. ADJUSTABLE GRID OVER-CURRENT FAULT, AUTO-RESET
3. ADJUSTABLE GRID OVER-CURRENT WARNING LED
4. ADJUSTABLE PLATE OVER-CURRENT FAULT, SHUTS DOWN HV SUPPLY IN 8.3 MS OR LESS
5. TUNE/ARC FAULT, UN-KEYS AMPLIFIER WHEN SEVERELY MIS-TUNED OR DURING TANK CIRCUIT
6. HV PRESENCE FAULT, HOLDS OFF KEY LINE IF HV NOT PRESENT OR LOW AFTER WARM-UP
7. FULL BREAK-IN QSK USING VACUUM RELAYS, LESS THAN 2.1 MS
8. T/R FAULT, HOT SWITCHING PROTECTION
9. FULLY ADJUSTABLE OPERATING BIAS USING THE TL-431 ADJUSTABLE PRECISION REFERENCE
10.ELECTRONIC BIAS SWITCHING, 2.5 AMP MAX
11.DUAL KEY-LINE BUFFERS, EITHER +5 -16 VDC OR GROUND WILL KEY THE AMPLIFIER,
(TTL AND CMOS COMPATIBLE)
12. COOL - DOWN DELAY FOR BLOWER, (OFF BOARD)
13. FRONT PANEL STATUS OF ALL FAULT AND OPERATING CONDITIONS.
14. ZERO CENTER TUNE METER, DETECTS INPUT AND OUTPUT POWER LEVELS AND DISPLAYS
VARIATION FROM OPTIMUM GAIN FIGURE
Bargraph Digital Display
CENTER TUNE BARGRAPH, 20 SEGMENT
2. 14 FAULT AND STATUS LEDS
3. HIGH REFLECTED POWER FAULT INTERFACED WITH TRIODE CONTROL BOARD, AUTO-RESET
4. 2.4 KW POWER BARGRAPH, ONE HALF OF MULTIMETER, 20 SEGMENT
5. 0 - 5 KV PLATE VOLTAGE BARGRAPH, ONE HALF OF MULTIMETER, 20 SEGMENT
6. 300 WATT REFLECTED POWER BARGRAPH, 10 SEGMENT
7. 0 - 1.5 AMP PLATE CURRENT BARGRAPH, 20 SEGMENT
8. 0 - 100MA GRID CURRENT BARGRAPH, 8 SEGMENT
IF YOU USE VACUUM RELAYS
AND COUPLER NOTE THE BELOW
*Note - the vacuum relays can not be installed in main RF deck due to radiation
from the open contact connections on the RJ1-A's. They need to be shielded
in a seperate RF encloseure.
*Note - most RF couplers like Bird 43 type will not work. They do not put out
enough voltage to drive the display ckt. You could try adding an op amp to
try to get the Bird coupler voltage up to about >2.5 vdc.
*Note - You may need to add a small trimmer cap around 10pf to ground in bypass
mode to tune out possible inductive reactance to get VSWR down to < 1.5:1
*Note - It is very important to keep all connection lead lengths as short as possible
*Note - If you want the relays to operate/release really fast apply +33vdc to them
and use a .33mf @500vdc capacitor across the relay coil instead of a normal
reversed bias diode setup.
BOX HAS AN INSERTION VSWR OF