Find on this site... Site Index  ·Exams ·Clubs ·Hamfests ·Addresses    Search site:    Call sign search:   ARRL Member Login... Username:   Password:    Register

Operating Activities Licensing News/Bulletins Services Educational Public Service Support ARRL Info Text-only/Printable

ARRL Products: VHF/UHF/Microwave (More) The ARRL UHF/Microwave Experimenter's Manual -- Information on design and fabrication techniques, propagation, antennas and feed lines, transmission media and much more. The ARRL UHF/Microwave Projects Manual Volume 1 -- Dozens of construction articles for transverters, preamplifiers, power amplifiers, antennas, and test and measurement equipment. The ARRL UHF/Microwave Experimenter's Manual software -- For use with The ARRL UHF/Microwave Experimenter's Manual. Microwave Handbook Volume 1 -- Components and Operating Techniques The ARRL UHF/Microwave Projects Manual Volume 2 -- More practical projects for the UHF/microwave experimenter.

Turn the regeneration control, all the way counterclockwise and set the volume control at about ½ way. Advance the regeneration control slowly until the detector goes into a soft hiss as it starts to oscillate. Adjust the volume control to a comfortable level. Reverse rotation of the regeneration control slowly, and the hissing should stop. Go back and forth over this point several times so that you may familiarize yourself with the sound. See how close you can come, in advancing the regeneration control clockwise, to the point where the hissing starts without actually making the hiss start. If you listen carefully, you will hear the background noise come up (in the absence of a signal). This is the most sensitive adjustment. for modulated (phone) signals.

For c.w. (Morse Code) signals, turn the regeneration control clockwise past the point where the hissing starts. Reverse the direction and slowly approach the point where the hissing stops. See how close you can get to this point without making the hissing stop. This is the point for greatest sensitivity for c.w. Strong c.w. signals will block the detector when it is adjusted for this most sensitive condition. In this case, turn the control clockwise as far as necessary to prevent blocking.

Use the Tuning/Frequency control to find a signal. Perform the above procedure on the signal you want to receive.

At times, advancing the regeneration control too far may result in a high pitched squeal. If this should occur, the control should be retarded. At times, changing the setting of the regeneration control will have some effect on the frequency, so it may be necessary to readjust the Tuning/Frequency control slightly to keep the signal in tune.

You should find plenty of signals at the right time of day or night, using a moderate antenna, that are strong enough to work a small loudspeaker connected to the output jack.