Archive for June, 2012

Vertical Antennas on HF Frequencies

June 20, 2012

There seems to be a lot of articles about vertical antennas and their design and use on the HF ham bands.  Back in the late 1950’s I moved into our first little house in the suburbs of  Columbus Ohio. I liked to rag chew with my friends on 75 phone on weekends.  Single Sideband was beginning to be heard on the band, but AM was still the most popular (as well as easy to understand and less expensive).  Because of space limitations, I decided on a vertical antenna.  It worked just fine for its intended use of Saturday Morning ragchews with other hams within 20 or 30 miles.  I used a couple Radio Shack ten foot tv masts fastened to the side of the house with a couple standoffs that held the masts about 12 inches away from the house.  The vertical was loaded with a large coil at the base.  The coil was tapped.  The coax from the basement was attached a few winds up from the base. The base and the coax braid were both grounded through a ground rod as I recall.  There were no radials.  there was another tap for the vertical mast.  Somehow I tuned for minimum SWR and/or maximum radiation.  I will have to research the actual circuit.  The  rig consisted of a homebrew single 813 amplifier fed from a Halicrafters HT-18 VFO.  There was no big modulator.  Instead, I used the HT-18 in its fm mode, which was narrowband, and produced a readable signal on the AM mode of receivers of that time. 

It was fun.  In general, I believe the more wire the better signal.  A good 40 meter vertical will work very well, but, remember, it’s a lot easier to put up a quarter wave vertical on 40 meters that it is on 80.  With a great match and efficiency,  a vertical should  get out very well..

Today my choice is still a dipole.  More later  Glenn NN8G

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QRP HISTORY IN THE MAKING?

June 15, 2012

Just received an email from a ham in South Carolina that used our  Pastime Projects “Look Ma” 12K5 tube 40 meter cw oscillator kit to make contact with a fellow QRP enthusiast in Pennsylvania using his mini milliwatt kit on the 40 meter band.  Here are some excerpts from his email “This is the second qrp rig that I have built, and I have to say, it is quickly becoming my favorite” …” It is a simple kit to build” … “The only thing I did not like was the crystal did not fit into the beautiful ceramic crystal socket that was included in the kit”. “I would recommend this to anyone who loves to build and maybe learn something new”…”I really hope you guys continue to sell this rig…”

You will hear more from this Ham Operator.  Sure got us excited.  Very best regards  Glenn  www.pastimeprojects.comPastime Projects 12K5 Tube Type 40 Meter QRP Qscillator Kit