WD7S PRODUCTIONS
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WD7S TRIODE CONTROL BOARD
COMPLETE CONTROL AND PROTECTION
FOR HOMEBREW OR COMMERCIAL
GROUNDED GRID LINEAR AMPLIFIERS
GROUNDED GRID TRIODE AMPLIFIERS REQUIRE SEVERAL FORMS OF PROTECTION TO KEEP THEIR TUBES AND OPERATORS SAFE. THE WD7S TRIODE CONTROL BOARD CONTAINS FEATURES FOUND ONLY IN TOP OF THE LINE COMMERCIAL AMPLIFIERS. THESE ADVANCED FEATURES ARE NOW AVAILABLE TO THOSE OF US THAT WISH TO HOMEBREW OUR OWN EQUIPMENT.
THE FOLLOWING FEATURES ARE INCLUDED IN THE CONTROL BOARD AND ASSOCIATED CIRCUITRY;
SUPPORTS HIGH VOLTAGE BIAS FOR GS-35B ON BOARD, REQUIRES CUTTING OF ONE TRACE TO ENABLE.
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ADJUSTABLE WARM-UP TIMER; HOLDS OFF HV AND KEY LINES |
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ADJUSTABLE GRID OVER-CURRENT FAULT, AUTO-RESET |
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ADJUSTABLE GRID OVER-CURRENT WARNING LED |
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ADJUSTABLE PLATE OVER-CURRENT FAULT, SHUTS DOWN HV SUPPLY IN 8.3 MILLISECONDS OR LESS |
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STEP-START HV TURN ON, (SOFT-START) |
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TUNE/ARC FAULT, UN-KEYS AMPLIFIER WHEN SEVERELY MIS-TUNED OR DURING TANK CIRCUIT ARC, AUTO-RESET |
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HV PRESENCE FAULT, HOLDS OFF KEY LINE IF HV NOT PRESENT OR LOW AFTER WARM-UP |
| AIR FAULT, SHUTS DOWN FILAMENT SUPPLY IF AIR FLOW NOT PRESENT WITHIN 5 SECONDS AFTER POWER APPLIED (AIR SWITCH NOT INCLUDED) |
| ON-BOARD FILAMENT PRIMARY SSR, 5 AMP MAX, SSR INCLUDED IN KIT |
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FULL BREAK-IN QSK USING BUILDERS VACUUM RELAYS, LESS THAN 2.1 MS |
| T/R FAULT, TRANSFER RELAY HOT SWITCHING PROTECTION |
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FULLY ADJUSTABLE OPERATING BIAS USING THE TL-431 ADJUSTABLE PRECISION REFERENCE |
| SOLID STATE BIAS SWITCHING, 2.5 AMP MAX, (CONTROLLED BY KEY LINE, NOT RF) |
| DUAL KEY-LINE BUFFERS, EITHER +5 TO +16 VDC OR GROUND WILL KEY THE AMPLIFIER, (TTL AND CMOS COMPATIBLE, NO NOISY RELAYS) |
| INSTRUCTIONS FOR COOL - DOWN DELAY FOR BLOWER, (OFF BOARD) |
| FRONT PANEL STATUS OF ALL FAULT AND OPERATING CONDITIONS, NO MORE GUESSING WHICH FAULT TRIGGERED THAT SINGLE FAULT LED |
| ZERO CENTER TUNE METER, DETECTS INPUT AND OUTPUT POWER LEVELS AND DISPLAYS VARIATION FROM OPTIMUM GAIN |
| LOW VOLTAGE REGULATED POWER SUPPLY ON BOARD, SAVES VALUABLE SPACE AND SIMPLIFIES INTERCONNECTIONS, TRANSFORMER INCLUDED IN KIT |
| SOLID STATE RELAYS USED FOR ALL AC SWITCHING, NO MORE WELDED CLOSED OR DIRTY RELAY CONTACTS, (HV AND HV STEP-START SSR's ARE OFF-BOARD AND USER SUPPLIED) |
| 120 OR 240 VAC SUPPLY, PLEASE SPECIFY |
| COMPACT BOARD SIZE, 4 X 8 X 2.0 INCHES (WDH) |
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PARTS LIST AND COMPLETE INSTRUCTIONS INCLUDED |
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SINGLE SOURCE FOR ALL COMPONENTS (MOUSER), NO SHOPPING AROUND FOR HARD TO FIND PARTS |
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AVAILABLE AS COMPLETE KIT INCLUDING ALL ON-BOARD PARTS |
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KIT
DOES NOT INCLUDE OFF-BOARD PARTS OR MOUNTING HARDWARE |
ALL OF THE ABOVE FEATURES ARE ACCOMPLISHED WITHOUT THE USE OF RF SENSITIVE TTL OR CMOS USING THE COMMON LM339 COMPARATOR AND ONLY A HANDFUL OF DISCRETE DEVICES. ALL IC'S ARE IN SOCKETS TO MAKE REPLACEMENT AND TROUBLE SHOOTING EASY IF EVER REQUIRED.
ALTHOUGH
HIGH SWR PROTECTION IS NOT INCLUDED, THE SOFT FAULT LINE IS BROUGHT OUT TO THE
BOARD CONNECTERS FOR INTERFACING TO ANY NUMBER OF OUT-BOARD PROTECTION DEVICES
INCLUDING THE DS-1 BARGRAPH DISPLAY MODULE
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