As Monday morning is housework time here, I might put my WSPR 500mW W5OLF beacon on for a while.
6 Mar 2023
Upcoming optical tests on 481 THz
It is years since I did optical experiments. My current plan is to do some local tests with QRSS bouncing off buildings. If these are successful, I want to try an "over the horizon" test with G4HJW.
My first task will be to install Spectran 2 software as this will be needed to decode QRSS and to check the signal margins.
Muntjac deer poo - NOT amateur radio
Bet you never expected this!
In recent weeks we have had a lot of these small deer in our garden. They have eaten some plants. When I cut the grass for the first time this year recently I noticed they left me a small "gift".
Club 72?
Some years ago there was a Russian QRP club that was quite active on 20m CW.
At the moment Russia is not in our good books over Ukraine, but I personally have no issues with the Russian people. Indeed, at the height of the "cold war" many Russians were worked and, via the medium of amateur radio, barriers were broken down. All were human beings just like us!
In my view we have to keep politics out of amateur radio. One of the great things about our hobby is we are all equal whether we come for Russia, the USA, Ghana or wherever. If will be a sad day if barriers are ever erected.
Does Club-72 still exist?
Mizuho MX2
This was an SSB/CW 2m 200mW handheld. I think it dates from the 1980s. In its time I worked some great SSB DX with mine when out portable. I still have one, but it has not been used for years. By modern standards it was not too small. As I recall, it was let down by poor battery life.
See https://sites.google.com/view/g3xbm4/home/vhfuhfmicrowaves/vhfuhf-commercial-rigs/mizuho-mx2.
FT8 on the FT-710AESS
One of my aims this week is to try FT8 on my FT-710. As a keen QRPer, I usually run low power and this will be no exception. In the end I overcame my issues with noise on FT8 RX with the IC-705. I hope this is not an issue on the FT-710. If it is, I shall add ferrite chokes on the USB cable between the rig and PC.
5 Mar 2023
Dalham - NOT amateur radio
We like to do a circular walk around the village of Dalham near Newmarket. This is the lane back to the village. Delightful.
Ferrite rod TX antennas
Ferrite rods are commonly used as RX antennas on MW and LW. They are compact and efficient for their intended purpose. Their use as TX antennas is almost non-existent.
As long as the ferrite is suitable for the frequency and as long as the ferrite is not in saturation, they may be used on TX. This implies very low power, but we know on WSPR and possibly FT8, long distances may be spanned with very low power indeed. Certainly great ranges have been covered with milliwatts and microwatts.
Some years ago, I did some TX tests with ferrite rods and the results surprised me.
In absolute terms, I have little idea about their loss compared with, say, a dipole. At 630m and 160m, antenna efficiencies are often -30dBd or worse, so they could be far better than we might expect. They certainly are small! Some people have bundled several rods together. I have not tried this.
This is yet another area in which radio amateurs can carry out useful research. Be careful that the ferrite rod alone is doing the work and you are not coupling into a bigger antenna nearby.
In my view ferrite rods "compress space" within the rod. As such, they could be used as magnetic or loading in E-field antennas.Remeber to keep power very low.
See https://sites.google.com/view/g3xbm4/home/antennas/ferrite-rod-tx-antennas .
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