Sunspots and 10m - Wed May 27th 2015

Sunspot number has fallen to 48 today (K=1), lower than recent weeks, and 10m is again forecast to be "poor".  Es may, of course, liven up 10m and 6m.

UPDATE  1042z:  OE6PWD (1232km) and IZ6QZB (1475km) recently spotted my 500mW WSPR beacon on 10m Es.

UPDATE 2006z:  According to local G4IKZ my dT (ever after a spot-on resync to internet time) is way off (greater than 4 seconds off) . I sync to internet time every 5 minutes on 6m and use this clock to sync my WSPR-AXE-CW beacon, normally once a day.  I'd be interested to know the dT that others measure on my 10m signal.

Early 10m Es

As early as 0550z my 500mW 10m WSPR was being spotted in Italy. This is very early for Es. I shall get back on 6m WSPR later.

VLF upconverter

VLF upconverter

Some years ago I was looking for a simpłe VLF upconverter (to receive SAQ) and came up with the simple circuit shown in the link. This was later improved by HB9DAO. The improved design is also shown.

If you want a simple introduction to VLF or LF listening these circuits may give you some ideas. It would not be suitable for serious amateur VLF use over any distance when high dynamic range, long integration periods, and very narrow bandwidths are pretty essential.  It is ideal for reception of commercial VLF signals and time standard transmissions.

See https://sites.google.com/site/g3xbmqrp3/vlf/vlfconv .

Cranial Osteopathy for Stroke - NOT amateur radio

I still have several stroke related issues (feel drunk when walking, tire easily, poor thin liquid swallow, poor voice), so today I started a series of cranial osteopathy sessions with someone recommended to me in Cambridge. The first session went well and I have fixed up a couple more sessions.  Some people swear that this works, whereas others say it is "quack medicine".  I go open-minded.

Time will tell if these sessions help with my symptoms. Although I am improving, the pace has slowed considerably so I am game to try anything that may help. After all this time I still do not feel right. I just want to get my old self back!

Back on 6m WSPR tomorrow

As our "Kent" grandchildren return home tomorrow and our "London" grandchildren arrive until Saturday, I should be back on 6m WSPR tomorrow. I get my shack back tomorrow as our "London" grandchildren are old enough for beds. This means that from around lunchtime I shall be active on both 10m and 6m WSPR.

UPDATE 1818z:   10m WSPR has been quiet today.  EA8BVP (2986km) has spotted me several times again by F2 and DK6UG (633km) by Es, but otherwise just locals. So far, at least, a very quiet day on 10m. As yet, on WSPR this has been a subdued season on both 6m and 10m. I don't think I've missed much on 6m these last few days.

Sunspots and 10m propagation - Tues May 26th 2015

Sunspot number is little changed at 66 (K=1) and 10m propagation is again expected to be "poor".

Apart from locals G4IKZ and G4KPX only early F2 spots from EA8BVP (2986km). No, what I would call , "real" DX  yet on 10m despite the undisturbed conditions. No Es seen here on 10m. I am not currently on 6m as I cannot access the shack PC easily.

10m BitX transceiver

I notice that someone has created a 10m (28MHz) version of the BitX transceiver. Yes, all would like more details but we don't know who you are!

Anonymous said:  "I have successfully designed and built a 28MHz version of the BITX transceiver. The main reason for this project was to drive homebrew transverters for 6, 4 and 2Metres. Contact me if you would like details."

Fourbox transceiver

G7CKF's Fourbox

Jenny, G7CKF  has now taken the 2m Fredbox design and created a 4m version called the "Fourbox".

Hi Roger,

    I feel I should drop you a line with my thanks and the link below, I've used your QRP AM transceivers as the basis for a 4M transceiver and published it on my blog. I've come back to amateur radio after a 20 year absence and since construction was always my main interest in the hobby I reached for the soldering iron.
http://thekeywordgeek.blogspot.co.uk/2015/05/a-transceiver-for-not-lot.html
There is no sparkling new insight to be had from it as it's pretty much your fredbox with slightly bigger coils. There is no crystal because I am cheating and using a Raspberry Pi clock generator to make my 70.260MHz.
My QTH is IO91lw, between Bicester and Buckingham and rather low lying. Very little 4M activity hereabouts, sadly, so the chances of my actually working anyone with it are slim. But that's not really the point of building, is it.
Anyway, hope you find it of interest, and thanks again for sharing your designs.

Jenny, G7CKF

Optical communications over the horizon

I have been too unwell to do this recently, but not long before my brain bleed (Sept 2013) I was amazed at optical communications over the horizon, non line of sight (NLOS) using clear air scattering.

The inspiration for all my optical experiments came from Stuart Wisher G8CYW who did a great series in RadCom a few years ago.

Testing optics

My home made transmitter only consumed about 0.7W from a red LED bought on the internet. My homemade RX and TX used homemade optics based around cheap drain pipes and cheap magnifying glasses. The whole RX and TX were simple and low cost. Only simple test gear was needed too. It is a bit like microwaves, but easier to build and test.

There was no sign at all of the TX beam in the sky.  All alignment used dead reckoning with some panning at the RX end to find the TX.

Using free PC software and QRSS3 helped as bandwidths as low as 0.37Hz were possible.

When fitter I want to try infra-red LEDs instead.

See https://sites.google.com/site/g3xbmqrp3/optical/481thz-nlos.

Sunspots and 10m propagation - Monday May 25th 2015

Sunspot count is 74 today (K=1) but 10m propagation is again expected to be "poor".

UPDATE 1253z:   So far today, apart from a couple of locals on 10m, only CT1JTQ (1843km) by Es. No DX seen, well not yet, on 10m WSPR.

UPDATE 1834z:  A little Es and single hop F2 spots from EA8BVP (2986km) but no "real" DX on 10m so far today.