I have been a licensed radio amateur since 1992, currently active on SSB, some digital modes and CW, on the amateur radio HF bands. I especially enjoy the experimental aspects of this hobby. I hate contests, but I love them when lazily receiving a large chunk of 20m band on sunday mornings...
Sometimes I let my computer do all the radio work through WSPR.
Information and activities
- I usually operate from San Gavino Monreale: JM49JN
The main radio is an ICOM IC-765 along with a TS-140S for backup. An old YAESU FT-747GX, on loan from IS0DZE, is also rarely used.
A KENWOOD TM V71 for FM VHF and UHF is connected to a COMET GP-5 on the roof.
Operation is either CW QRP or 100W SSB - My CW is awful at the moment, please be patient!
I also have a nice wideband SDR receiver: ELAD FDM-S1 along with its optional bandpass filter board ELAD FDM-SFE. The software employed is of course LINRAD by Leif
Åsbrink (SM5BSZ). LINRAD is one of the best examples of SDR software that allows extreme customization, reliability and open source development.
You can turn LINRAD into an advanced spectrum analyzer, a radio direction finder, you could record for ten hours the whole MW band or receive
EME signals or FM stations reflected from airplanes. Of course it has a steep learning curve at first.
Center-fed vertical doublet 12m high on a spiderbeam pole about 120m from the shack in the house.
The feed is connected to a 450 Ohm parallel feedline about 20m long and sloping at 45° towards ground. Feedline is connected to a remote
automatic antenna coupler (SGC SG-239). The remote coupler is connected to the shack via a 100m long RG-213 coaxial cable laying on the grass
inside a corrugated electrical conduit. There are two current baluns both coupler-side and radio-side made by 6 turns of RG-213 on large
ferrite (material 43) toroidal cores. The power supply to the coupler is injected radio-side via a home-made circuit.
Recently I removed the 450 Ohm parallel feedline and moved the tuner in the middle of the pole. The results are good, but finding a good match on 21MHZ is tough.
This setup works satisfactorily from 40m up to 10m. Even some occasional 80m contacts are possible in a pinch.
The main advantage of this antenna system is that it has very low angle vertical radiation and low loss since the ground conductivity is
about 30mS/m. The parallel feedline has very low loss even when the SWR is over 10:1 and the RG-213 has no more than 2.5db loss at 28MHz
since it sees a 50 Ohm load. The large distance from the house assures that no home-made noise reaches the antenna. I live in a rural area
and my nearest neighbor lives about 200m from the antenna. I have no high-voltage lines nearby: if you can hear me, I will too!
I added a ~5m vertical over the long (~160m) metallic fence (NW-SE direction) and connected the coaxial cable directly to the vertical and to the fence
used as ground. The results are very similar to the vertical dipole on 14MHz.
After a long time, I finally took the time to install an active receiving antenna. I choose to buy the kit by Chavdar Levkov LZ1AQ
COMET GP-5 on the roof for VHF and UHF.
- Keys: Begali Simplex and Military J-38 Vertical key.
- I have an active experimental beacon under the roof on 30m
(10.130 MHz). It's impossible that you'll hear it, but if you happen to, please let me know! (its antenna is just a 2m wire...) A list of many HF Beacons...
- Info: if you have any technical question please contact me at cogoni AT gmail DOT com
Last modified: Saturday, 10-Jun-2017 23:30:00 CEST