WD7S PRODUCTIONS
HOMEBREW GALLERY-4
YC-156 SIX-METER DESKTOP
[INDEX] [GALLERY-1] [GALLERY-2] [GALLERY-3] [GALLERY-5] [GALLERY-6]
CLICK ON IMAGES FOR FULL SIZE VIEW
FRONT VIEW OF TANK COMPARTMENT
NOTE ADJUSTABLE TAP POINT
TOP VIEW OF COMPLETED TANK
WITH AIR CHIMNEY IN PLACE
UNDERSIDE VIEW OF CATHODE
COMPARTMENT
AMPLIFIER USES PRESSURIZED ANODE AND CATHODE
COMPARTMENT WITH AIR SUPPLIED AT CATHODE
FRONT CORNER VIEW AFTER
INTERCONNECTIONS COMPLETED
SIDE VIEW OF REAR PANEL
SHOWING TRANSFER RELAY
AND DIRECTIONAL COUPLER ENCLOSURES
FILAMENT RHEOSTAT MISSING
SIDE VIEW WITH INTERCONNECTIONS COMPLETED
FRONT VIEW
SPECIFICATIONS AND SOME EARLY NUMBERS 02-27-02
PLATE
VOLTAGE, NO LOAD, 4450VDC
PLATE VOLTAGE @ZSAC, 4100VDC
PLATE VOLTAGE AT 66DBM OUTPUT 3600VDC
CAPACITOR BANK, 47UF, (10 X 470UF)
ZSAC, 400MA, BIAS VOLTAGE 17 VDC
DESIGN LOAD IMPEDANCE, 1350 OHMS
DESIGN FREQUENCY, 50-50.2MHZ
TANK CIRCUIT, PI-L
LOADED Q, 23, (RL/XC, OLD WAY)
LOADED Q, 36, (OVERALL)
INPUT T NETWORK Q, 5
INPUT IMPEDANCE RANGES FROM 33 OHMS AT 62DBM OUTPUT TO 22 OHMS AT 66DBM OUTPUT
AS MEASURED BY SUBSTITUTION OF REAL PART AT TUBE WHILE COLD
DRIVE
+47DBM, OUTPUT +62.04DBM, GAIN +15.04DBM, EFFICIENCY 36.8%
DRIVE +50DBM, OUTPUT +64.77DBM, GAIN +14.77DBM, EFFICIENCY 55%
DRIVE +51DBM, OUTPUT +65.44DBM, GAIN +14.44DBM, EFFICIENCY 63%
DRIVE +52DBM, OUTPUT +66.28DBM, GAIN +14.28DBM, EFFICIENCY 65%, (DESIGN RL FOR
MATCHING)
FEED-THROUGH POWER NOT ACCOUNTED FOR
DRIVE
USED, 30WPM DIT STRING
WATTMETER, NYE VIKING RFM-005 PEAK MODE
DUMMY LOAD, BIRD 2500 WATT WATER COOLED, (USED SPARINGLY)
HARMONICS
AND SPURS >53DBM BELOW FUNDAMENTAL, DOES NOT MEET FCC SPECS FOR THIS
FREQUENCY
WITHOUT BAND PASS OR LOW PASS FILTER
THE
TUNE CAPACITOR WAS INCLUDED FOR POSSIBLE EXPERIMENTATION AND IS NOT USED OR
REQUIRED
THIS TUBE DOES NOT DRAW GRID CURRENT BELOW 50DBM OF DRIVE AND ONLY 44MA AT 52DBM
DRIVE, (DESIGN RL)
NO THERMAL DRIFT OR COMPONENT HEATING WAS OBSERVED AT THE 66DBM OUTPUT LEVEL
THE
AMPLIFIER USES THE FOLLOWING BOARDS
TRIODE CONTROL, DS-1, DS-PS, HV-2, AND A NEW 5KW DIRECTIONAL COUPLER, DC-1
MORE TO COME, STAY TUNED!
