Later today, all being well, I intend to finish the rebuild of my loop for 10m.
I have still to decide on WSPR or FT8. Before doing it, I shall try to (roughly) cut the coax capacitor to close to the correct length, having found out what capacitance I need from the online loop calculator.
My capacitance meter that has not been used for about 7 years! The battery probably needs replacing! I hope it has not leaked.
UPDATE 1035z: The gods are with me! Some time ago, I must have removed the battery to use it somewhere else. I just put a new battery in and the capacitance bridge is working fine. According to my calculation I need about 43pF with a 0.6cm thickness pipe with a circumference of 2m. I shall recheck the pipe cross-section. It is thin bore copper pipe used in central heating systems. If I cut the length slightly long, I can snip a bit off until it hits resonance. The very most I can run is 20W (most times 500mW WSPR or 2.5W FT8) so I am unlikely to have problems with high voltages. In the past I even used a dead ordinary 365pF air spaced variable without issues in a loop antenna.
UPDATE 1535z: The loop is now finished and operational. In the end I decided on FT8 and used a 365pF airspaced variable to get to frequency. It is very sharp! This is a good sign. It seems a few dB up on the other loop judging by local reports. Using the airspaced variable C means that the loop antenna can be used on other bands. The photo shows the completed loop. It was much harder than I expected. Years ago it would have been trivial.
UPDATE 1749z: Just 2 locals have spotted me so far today on 10m FT8 TX with my 2.5W to the better indoor loop antenna.
23 Apr 2020
Living in the moment - NOT amateur radio
We live in strange times. One thing we are all learning is to live in the moment and enjoy what we see. Most mornings we do a walk. It is surprising what beauty is all around us if we look.
The next solar cycle
We are very close to the solar minimum and next year we can expect solar conditions to get better. This will be the first solar cycle in which FT8 will be used near and at the peak. As FT8 is better than SSB or CW, it will be interesting to see how this alters things. SSB and CW activity could be lower.
22 Apr 2020
10m magnetic loop
Many years ago I made a loop antenna for 10m using central heating copper pipe. Bits for this have been in the garage for about 7 years! For the capacitor I used a length of coax cut to resonate.
Since my stroke things are much harder. I am trying to rebuild it as it should be much more efficient than the loop I am currently using. Rebuilding it is much harder than I expected. If on WSPR it can be left on the air 24/7 using my beacon. FT8 might be more productive even if less sensitive.
Since my stroke things are much harder. I am trying to rebuild it as it should be much more efficient than the loop I am currently using. Rebuilding it is much harder than I expected. If on WSPR it can be left on the air 24/7 using my beacon. FT8 might be more productive even if less sensitive.
15m FT8
Rather earlier than usual, I am on 15m FT8 with 2.5W and the 45cm indoor loop. It is now 0615z. No spots yet.
UPDATE 0922z: No spots.
UPDATE 1040z: One G spotted on RX and one G spotting me so far.
UPDATE 1215z: 5 stations in Europe and North Africa have been spotted on 15m FT8 RX. So far, just the 1 station has spotted my 2.5W.
UPDATE 2011z : QRT.
UPDATE 0922z: No spots.
UPDATE 1040z: One G spotted on RX and one G spotting me so far.
UPDATE 1215z: 5 stations in Europe and North Africa have been spotted on 15m FT8 RX. So far, just the 1 station has spotted my 2.5W.
UPDATE 2011z : QRT.
Birthday boy - NOT amateur radio
One of our sons is 42 today. This photo of when he was 35 appeared as a FB memory today.
The second photo shows them today.
The second photo shows them today.
21 Apr 2020
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