With room for introducing many improvements, especially a better audio section, this is the most basic REGENERODYNE radio receiver circuit. A simple mixer  stage, the regenerative detector and a one stage audio amplifier triode...
In my latest version the audio module consists of a triode followed by a tetrode... in actual practice a ECL82 or 6BM8.... The power supply is on a separate chassis, and provides regulated DC to the filaments of the regenerative detector. The regenerative detector in the prototype tunes from 2.5 to 4..5 megaHertz.... With a 4 megahertz
crystal in the oscillator feeding the mixer stage, the receiver
tunes from 6.5 to 8.5 mega Hertz. Using a 6 mega Hertz
crystal the radio tunes from 8,5 to 10.5 megaHertz.
The experimental regenerative detector has to be well shielded to avoid picking up direct signals leaking from the antenna into its
basic 2.5 to 4.5 mHz tuning range.... something that can be noticed
at night... Testing many crystals to check other tuning ranges is
a lot of fun.... You may want to add an RF amplifier stage and a dual tuned bandpass input filter to further improve this marvelous little radio....

Back on line

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arnaldo.coro at gmail dot com

Just checking if this old BLOG was still on line !
Please report if any of you can see this post
send mail to
arnaldo.coro@gmail.com
Maybe it can be put back to work !!!
73 and DX
Arnie Coro
CO2KK
Host of Dxers Unlimited
Radio Havana Cuba

Solar cycle 24 F 10.7 cm Radio Flux Progression

Solar cycle 24 Sunspot Number Progression

CO2KK Sloping wire antenna for

CO2KK´s Easy to make and install SLOPING LONG WIRE ANTENNA FOR 6 METERS OPERATION.
It does require a PI network antenna tuner that must be located at the base of the vertical part of the antenna.
Vertical part is a minimum of one wavelength long at 6 meters
The radials * counterpoise* are of 1/4 wavelength each , spreading around
in a circle at the extreme end of the sloping wire.
The sloping wire must be at least one meter above the ground
If you make the sloping wire longer, , that is more than three
wavelengths .the antenna's directional properties will be enhanced

RE; 6 meters band sloping long wire antenna with counterpoise

6m (50Mhz) Long wire antenna

Description by Arnie Coro CO2KK
There is another form of long wire antenna which provides uni-directional coverage and is easy to build.

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Here is the description.

From the transmitter or transceiver, you go to an antenna tuner via coaxial cable. The tuner is placed at the base of the antenna, not at your operating position.

From the tuner's single ended output comes a wire that first goes STRAIGHT UP for about ONE WAVELENGTH at 50 mHz...
Then the wire is bent and slopes VERY GENTLY in the direction of the desired coverage, You want the wire to extend itself for no less than 5 wavelengths, although shorter versions work quite well too, but are not SO DIRECTIONAL.
The wire SLOPES until it ends at a height of about ONE TO TWO METERS ABOVE GROUND.... There you tie it to a small mast... THEN.... tied to this small mast you need to place no less than 3, and much better 5 one quarter wavelength radials , that act as a counterpoise... The radials will kindly help to hold the small mast in a vertical position... You can use very small insulators for the radials, or tie them with dacron or nylon lines ( I prefer to use dacron lines similar to those used for sailboats ).

REMEMBER to aim your antenna to SLOPE in the DIRECTION that you want to communicate with....
It shows a gain of no less than 5 to 6 dB over a horizontal dipole when the wire length is about 30 to 40 meters....

The antenna seems to work also on 10 meters , with the appropriate tuner, and I have tested it on 2 meters too, but have yet to do some really good comparative tests against my "standard" 5 element portable yagi.
This VERTICAL 1 wavelength + HORIZONTAL SLOPING 5 to 7 wavelength antenna + RADIALS, can be taken on a reel, and the wire can be really light... a lot easier to transport than a YAGI or a QUAD, and certainly a lot easier to build and to put in place. YES... YOU ARE RIGHT... I always USE A TREE ( when available) to hold the VERTICAL PART OF IT !!!

Hope this helps those in need of a very simple, low cost, unidirectional field antenna for VHF use

Arnie Coro CO2KK
Host of Dxers Unlimited
Radio Havana Cuba
e-mail : inforhc@enet.cu
 

Postal address
Arnie Coro
Dxers Unlimited
Radio Havana Cuba
Po Box 6240
Havana
CUBA 10600