Yesterday evening I witnessed the sunset from my backyard garden.
I realized that it is amazing that a star at a distance of 150 million kilometers from us affects the propagation of radio signals on earth. During daytime the solar wind presses the Kennelly-Heaviside layer closer to the earth, thereby limiting how far it can reflect radio waves. The effect is also influenced by the amount of sunspot activity.
For a change, last week I was active on 160 m. With my end-fed longwire antenna - in the evening hours - I managed to work a couple of stations. One of them was HB9EFK. This was my first with Switzerland on 160 m.
Yesterday I powered up my 4 m equipment. To my surprise I saw EA and 9H stations. No dx QSO's yet. I did make some local 70 MHz QSO's though. Looks like the Es season is ready to start.
Case 1
Lately I visited the National Museum of Antiquities (‘Rijksmuseum van Oudheden’) in Leiden. One of the many fascinating objects that amazed me was ‘The Stele of Hatiay’. It shows general Hatiay announcing – in name of his king - that he has established many new sacred memorials (1330-1320 BC). That’s what the text near the stele tells us.
I was intrigued
by the triangular shaped device that Hatiay holds in his hand. If you have a
close look at the smaller persons, some of them also hold similar devices. In
my view the triangular shaped units look like microphones. With a little bit of
phantasy we see here something that looks like an early version of an internet
teams meeting… Maybe the microphones operate wireless since there is a small
piece of (antenna) wire coming from the triangles…
Last weekend I re-discovered the Uniden Bearcat BC860XLT VHF/UHF scanner. I did not use it for over 10 years. It is a remarkable receiver covering the frequency range 29 – 956 MHz. It contains 100 channels to store favorite frequencies.
I was glad to find out that the device still works fine.
Receiving aircraft AM voice transmissions from Rotterdam Airport and vessel voice communications from the Northsea confirm that
the unit is in good shape. Nice toy !
Specs:
Just found one of my old CB QSL cards. This one is from 1978. At the time I used a 23 channel CB transceiver "North Star". Memories..channel 14, 27.125 MHz AM .. and 4 Watt RF output into a DV27 mobile antenna.
How did your QSL card look like ?
From AliExpress I ordered this nice PCB with a logaritmic power detector circuit onboard. The electronics is designed around an AD8307 integrated circuit. The detector should operate in the range 1 - 600 MHz. DC input anywhere between 6 .. 15 Volts.
All ingredients are there to realize a nice S-meter / RF Pwr-meter.
JostyKit was the name of a Danish manufacturer that sold nice Do-It-Yourself kits. One of them was the HF65. In fact a free running oscillator that operated in the FM broadcast band (and below and above J, according to the specification sheet somewhere between 60 -145 MHz). A 2N2219 transistor provided appr. 1 Watt HF. The modulation was a mix of FM and AM, but on a regular FM tuner one could easily hear the HF65 and the sound quality wasn’t even bad.
Anyway around
1977 I played with this nice device and was able to broadcast some music in the
neighbourhood.
I think many liscenced HAM operators nowadays started their radio experience with transmitters similar to the HF65.
T1 = 2N2219
T2 = BC172
Lately there is quite a lot of attention for the 8 m band (40 MHz). Transmissions are done from Ireland, UK and Denmark for example.
This band could be interesting to explore for various reasons:
The 8-meter band shares many characteristics with the neighboring 6-meter band. However, as it
is somewhat lower in frequency it does display the better propagation mechanisms
via the F2 layer normally seen at HF. Also sporadic
E-propagation is common on this band in summer.
After I performed the MARS modification, my FT-450 is able
to receive 40 MHz signals. Of course the FT-450 input filters are not designed
for this frequencies.
I am working on a 8 m bandpass filter / pre-amplifier for the FT-450 to increase the sensitivity for this band.
Hopefully I will be able to tune in into 40.680 MHz - to receive FT-8 signals - soon.
First results;
For more than 10 years I have a piece of hardware in my junkbox that waits for an application:
It is an old school mechanical tuning device, most likely obtained from 'green' radio equipment. The tuning knob drives, tru a variety of gear wheels, a 100 Kohm potentiometer.
The only (German) inscription present says "Funk.stat.18.T"
