29 Jan 2020

Wayback machine - old internet sites

It is possible to find many old websites from the past that are old and long gone by looking on the Wayback Machine that archives and takes a snapshot of many closed websites. For example, today I viewed one of my websites created 23 years ago (www.lapr.demon.co.uk). I think my first ever website was created in 1994 using Compuserve. I shall have to see if I can find it!

A tip: keep a record of the URL of your old websites. Many of my old ones I can't remember, so I cannot do a search!

Crystal sets

It is some years now since I last played with crystal sets. If you have never tried these I urge you to have a go. These are powered entirely by the received signals, so no batteries or power source of any kind is needed.

Being envelope detectors, they are only really suitable for AM, although I have detected SSB and CW signals on mine in the past. There are even designs for band 2 FM using high-Q circuits and slope detection!

In the past, I have copied all over the world on a short wave crystal set. These were genuine receptions from the originating countries and not from relays nearer home. I have copied several amateur signals on 160 and 80m too.

See https://sites.google.com/site/g3xbmqrp3/hf/crystalset

See also https://crystalradio.net/crystalplans/index.shtml

BREXIT - NOT amateur radio

This Friday, the UK will no longer be in the EU. It has been a member for 47 years, after being famously blocked by General de Gaulle in 1963.  We eventually joined in the 1970s.  It will be a difficult year ahead with trade negotiations with the EU and other countries.

I have mixed feelings. There is a lot wrong with the EU and I feel the EU will be much weaker without the UK. On the whole, I favoured staying in the EU and trying to get change from within.

Having left, it is up to the UK to forge its place in the world. I hope we maintain close trading ties with the EU. That was why we joined in the first place. Federal Europe was never, as far as I know, ever in our thinking.

See https://www.bbc.co.uk/news/uk-politics-51287430

Linear time? - NOT amateur radio

We always assume that time is linear going from the past into the future. But what if time is an illusion? One thing is certain: we know so little about so much. It is entirely possible that in our future we will come to a different conclusion about many things. Think how our world view changed with Einstein and later quantum physics.

New houses - NOT amateur radio

It seems that every nook and cranny in our Cambridgeshire village is being used for "fill-in" houses. At the moment, houses are not selling well, but that does not stop developers keen to make a quick profit.

SSTV from ISS?

Southgate News reports that there is expected to be SSTV from the International Space Station on Jan 30/31st.

See http://www.southgatearc.org/news/2020/january/slow-scan-tv-from-iss-january-30-31.htm#.XjFNtfKTLnE

80m FT8 overnight

What strikes me is how similar results were to 160m FT8 recently. As before, I am still using the earth-electrode "antenna" in the ground. Overall, 769 stations spotted since yesterday afternoon.
80m FT8 RX here overnight
UPDATE 1322z: After remaining on 80m FT8 I was surprised to see a recent CQ (10W) was spotted by 6 stations with best DX spot being by LA7DFA (1311km). Earlier, I called a G station and enjoyed a solid 80m FT8 QSO. I am pleasantly surprised how well the earth-electrode "antenna" in the ground is performing on 80m FT8.

Cambridgeshire's most inspiring teacher - NOT amateur radio

A few days ago my wife was named in the local media as a candidate for most legendary teacher.

She enjoyed her time as a teacher and judging by all the pupils who stop her when shopping years later, she certainly made a lasting impression.

I am proud of her. There have been some very kind comments made about her.

Ferrite rod transmitting antennas.

This has appeared before, but I think it is worth repeating.

Ferrite rods can be used on TX as long as the ferrite does not saturate. This means low power.  I like to think of the high permeability as a "shrinking of space".  Indeed this is how I visualise ferrites work on RX.

Being a loop, they can be very narrowband, but will work when frequency is fixed such as with WSPR or FT8.

I have no idea what the "gain" is, nor have I any idea of the ferrite material that I used.  It is some years since these experiments were carried out.  The results astounded me.

See https://sites.google.com/site/g3xbmqrp3/antennas/ferrite_tx

See also https://en.wikipedia.org/wiki/Permeability_(electromagnetism)

Sunspots - Wednesday January 29th 2020

Solar flux is 74 and the SSN 11.  A=5 and K=3.