SCHEMATIC ONLY AM BCDST/SHORTWAVE GU-50 TUBE REGEN RADIO (510 khz to 15.8 mhz)

Description

This is a schematic diagram only of the radio in the following description. No construction manual or parts are included, but all parts values are shown on my hand sketched diagram, along with several pages of coil examples that I've made for many of my radios.
So if you are somewhat familiar with hands on construction of similar analog circuits from the earlier days of radio, then you should have no problem in making one of these for personal use. You may also order this item fully constructed and ready to go, as offered on my listings.
IT IS NOT WELL KNOWN BUT THE RUSSIAN GU-50 PENTODE TRANSMITTER TUBE MAKES A REALLY NICE REGENERATIVE RECEIVER. TO ME IT IS SIMILAR, BUT A SLIGHTLY BETTER PERFORMER, COMPARED TO THE OLD STANDARD US 1625 TUBE THAT YOU SO SEE SO OFTEN IN REGENERATIVE RECEIVERS.
THE SPECTRUM COVERAGE IS CONTINUOUS FROM ABOUT 510 KHZ IN THE AM BROADCAST BAND, UP TO ABOUT 15.8 MHZ SHORTWAVE, USING THE PLUG-IN COILS PROVIDED (SIMILAR TO THOSE IN THE PHOTOS).
I MOUNTED THIS RADIO ON WOOD CRAFT BOX, WHICH WOULD HAVE BEEN TYPICAL OF THE FARM RADIOS OF THE 30'S AND 40'S. THE WOOD FRAME HAS SEVERAL COATS OF URETHANE FINISH.
AS A BONUS I HAVE ADDED 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.
YOU WILL NEED A 12 TO 14 VOLT DC EXTERNAL POWER SUPPLY OR BATTERY FOR THIS RADIO. IT ALSO REQUIRES A 9 VOLT LI-ION RECHARGEABLE BATTERY FOR THE REGEN PLATE AND TRANSISTOR AMP CIRCUITS. THIS IS CONNECTED IN SERIES WITH THE INCOMING 12 VOLT SUPPLY, TO PRODUCE APPROXIMATELY 20 VOLTS DC OPERATING VOLTAGE (NO BATTERIES OR POWER SOURCE IS INCLUDED IN THIS LISTING).
THE MAIN TUNING CAPACITOR AND/OR DIAL APPEARANCE MAY VARY SLIGHTLY, DEPENDING ON WHAT I HAVE IN STOCK, BUT WILL ALWAYS LOOK SIMILAR TO WHAT YOU SEE IN THE PHOTOS.
YOU WILL ALSO RECEIVE A HIGH IMPEDANCE PIEZO HEADSET, USING DUAL PIEZO ELEMENT INSERTS. I MAKE THESE WITH NEW PARTS AT TIME OF ORDER (SEE PHOTO).
THIS RADIO HAS MAIN AND FINE TUNING, REGEN AND ANTENNA COUPLING CONTROLS ON THE FRONT PANEL.
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, AN ANTENNA COUPLING CONTROL IS PROVIDED FOR ADJUSTING TO DIFFERENT ANTENNA LENGTHS.
I GUARANTEE THIS RADIO WILL WORK IF PROPERLY CONSTRUCTED, AND USING APPROPRIATE POWER SOURCES AND AN ADEQUATE ANTENNA SYSTEM.
MAILING TO THE US ONLY.......