HIKER'S SHORTWAVE/AM BROADCAST 49 TUBE REGENERATIVE RECEIVER (SCHEMATIC ONLY)

Description

YOU ARE PURCHASING A HAND-SKETCHED SCHEMATIC ONLY OF MY VERSION OF THE HIKER'S 49 RADIO.
THE CIRCUIT SHOWS ALL COMPONENT VALUES, BUT NO PARTS ARE INCLUDED. THIS IS NOT A STEP BY STEP MANUAL, THOUGH I WILL INCLUDE A FEW TIPS ON OPERATION AND POSSIBLE COIL SPECS FOR DIFFERENT FREQUENCIES. IN ADDITION I'LL ALSO INCLUDE SOME GENERAL INFORMATION ON OPERATION OF REGENERATIVE RECEIVERS.
POPULARIZED BY THE HIKER'S SERIES OF THE 1930'S, FEW VACUUM TUBES EPITOMIZE THE OLD WORLD OF THE REGENERATIVE RADIO ART MORE THAN THE DUAL GRID 49 TUBE. IT HAS A 2 VOLT FILAMENT, RATED AT 120 MILLIAMPS.
THERE'S AT LEAST A DOZEN VERSIONS OF THIS RADIO SCATTERED ABOUT IN PUBLICATIONS OF THAT ERA, AND THE 49 TUBE REGEN RECEIVERS REMAIN POPULAR TO RADIO ENTHUSIASTS, EVEN TODAY.
THE 49 MAKES A WONDERFUL DETECTOR. CRISP, CLEAR AUDIO, AND WITH THE ADDED ONE TRANSISTOR HEADPHONE AMPLIFIER SHOWN IN THE CIRCUIT YOU'LL HAVE PLENTY OF VOLUME.
THE SPECTRUM COVERAGE WILL DEPEND ON THE COILS YOU WIND, BUT MOST ANYTHING IS POSSIBLE, FROM LONG WAVE, AM BROADCAST AND SHORTWAVE UP TO ABOUT 15 MHZ.
I MOUNTED MY RADIO ON WOOD CRAFT BOX, WHICH WOULD HAVE BEEN TYPICAL OF THE FARM RADIOS OF THE 30'S AND 40'S, BUT MAY CHOOSE TO USE A METAL CHASSIS, OPEN WOOD FRAME OR SLATBOARD CONSTRUCTION. THIS WILL BE YOUR DECISION TO MAKE.
AS ALREADY STATED, THIS CIRCUIT INCLUDES A ONE STAGE TRANSISTOR HEADPHONE AMPLIFIER, WHICH INCREASES THE VOLUME CONSIDERABLY. THE TRANSISTOR AMP IS PART OF THE CIRCUITRY, AND RUNS OFF THE COMMON DC BATTERY B+ LINE.
WITH THE LITHIUM-ION RECHARGEABLE BATTERIES INSTALLED, AS RECOMMENDED, YOU DO NOT NEED ANY ADDITIONAL EXTERNAL SUPPLY VOLTAGE. THE BATTERIES I USED ARE 4X OF THE 18650 ONE STANDARD 9 VOLT TYPE, BUT ANY NUMBER OF DIFFERENT CONFIGURATIONS IS POSSIBLE, SO LONG AS YOU PROVIDE THE NEEDED VOLTAGE AND CURRENT CAPACITY TO OPERATE THE RADIO.
HIGH IMPEDANCE HEADPHONES ARE REQUIRED FOR THIS RADIO, EITHER THE 2 TO 4K OHM INDUCTIVE TYPE OR A HEADSET CONSTRUCTED WITH PIEZO ELEMENTS.
THIS RADIO CIRCUIT HAS MAIN AND FINE TUNING, REGEN AND ANTENNA COUPLING CONTROLS.
YOU'LL NEED A WIRE ANTENNA OF AT LEAST 25 TO 50FT IN LENGTH, ALONG WITH A GOOD EARTH GROUND. A 75 TO 100 LENGTH ANTENNA WILL PERFORM BEST ON THE LOWER FREQUENCIES. AS STATED, THE CIRCUIT HAS AN ANTENNA COUPLING CONTROL FOR ADJUSTING TO DIFFERENT ANTENNA LENGTHS. THIS IS QUITE HELPFUL FOR OPERATING ANY REGENERATIVE RECEIVER.
PROPERLY CONSTRUCTED, ACCORDING TO MY DIAGRAM, THIS RADIO WILL WORK IF YOU HOOK IT UP PROPERLY.
AGAIN, YOU ARE PURCHASING A HAND DRAWN SCHEMATIC ONLY, ALONG WITH A FEW NOTES AND COIL DATA. THIS RADIO IS AVAILABLE FOR PURCHASE AS A FINISHED PRODUCT ON ANOTHER LISTING........KW7T