22 Dec 2014

472kHz today

M0EMM (192km) has been spotting me on 472kHz WSPR today along with spots from other stations. Overnight, PA0A (417km) was copying me.

These are the 472kHz WSPR spots using 5mW ERP and the earth-electrode "antenna" in the last 24 hours. Even using my "deaf" FT817 barefoot on RX and with this crude antenna system, I seem to copy plenty of stations.
Unique 472kHz spots - last 24 hours

Australian IR tests

VK4EBP reported that he has carried out successful tests over a 10km NLOS (non line of sight) path using infra red.

See Australian Optical DX   https://groups.yahoo.com/neo/groups/Optical_DX/info .

One of my aims for 2015, assuming I am fit enough, is more NLOS tests including IR over greater ranges. To maximise my chances I shall probably use QRSS3 again rather than rely on aural reception. My previous tests, using clear air scatter, was over a 8.5km distance.   Much further should be possible.

Sunspots and 10m

Sunspot number today has climbed to 159 but 10m propagation is forecast to be only "fair", so 10m propagation may not be as good as yesterday. So far this morning 4Z5SM (3523km) is the best DX spot of my 500mW 10m beacon.

UPDATE 1550z:  Martin G8JNJ reports 10m AM signals coming in well around 29.050MHz. I am getting plenty of USA WSPR reports of my 500mW beacon again today. Conditions on 10m certainly seem better than "fair".

21 Dec 2014

First and last USA 10m WSPR spots today

The first USA station to spot my 500mW WSPR beacon today was KD6A (6285km) at 1244z and the last was W3CSW (5886km) at 1822z. Best DX spot today was by ZS6BNE (9075km) at 2616z.

Apple - Panorama documentary

Last week, BBC's Panorama programme did a frightening documentary on factories used by Apple in China and on their tin supply chain in Indonesia. If such poor conditions are used by Apple, many other products will be produced in even worse conditions. As a user of Apple products I am appalled.

See Panorama, Apple's Broken Promises .

Of course, we in the West milk the low costs that such poor working procedures/conditions permit. With time, conditions will improve and the West will look to other low cost manufacturing areas for our low cost products. Sadly, our greed feeds this process.

Frighteningly, other products we buy are probably made in places that are far worse.

Andrew G6ALB tells me of a friend in the automotive industry who visited a Chinese supplier where he found workers using ordinary sun glasses to protect eyes from welding gear. After 6 months  the workers were totally blind. So they just got fresh workers to replace them!

Thanks to Steven G7VFY for most of this information.

UPDATE 1740z:  Sadly many (most?) of our electronics components will be made in sweat shops in the Far East. It is very hard to get away from this problem.

Sunspots

Sunspot number has fallen back to 120 (still pretty respectable) and 10m daytime propagation is expected to be "good".

20 Dec 2014

Simple 10m DSB transmitter

From Steven, G7VFY comes news of a very simple 10m DSB transmitter from the blog of KA7OEI. This is an experimental very low power transmitter. It is unlikely to be of use in serious applications, but the range might surprise some.  On 10m, the antenna is efficient and on a clear frequency it has the potential to get a long way. Over 1000km would not surprise me on a totally clear frequency. After all, 1mW (or so) is about 53 if a 100W signal was 59+12dB. On 10m such signals with 100W are very possible.

See http://ka7oei.blogspot.co.uk/2014/10/the-pointless-10-meter-dsb-qrp.html .

472kHz

I have been on 472kHz WSPR most of the day using 5mW ERP to the earth-electrode "antenna" both on RX and TX.

On RX DK7FC (669km) continues to put out his very strong signal.  It is no wonder he is regularly copied in the USA.

On TX I am still being copied by G0LRD (25km) and G8LCO (58km).

G3YMN (112km) is a new reporter in the last 24 hours. Thank you for your spots.

UPDATE 2148z:  A new reporter, and new country, copying my 5mW ERP from the earth-electrode "antenna" this evening - Finbar, EI0CF (602km), using his Perseus RX and 120m long Beverage antenna. Report was -27dB S/N at 2218z.

Optical communications - over the horizon (NLOS)

The DX record for communications at optical frequencies is phenomenal these days. There is a growing interest in communications over non line of sight paths (NLOS) using cloud-bounce or clear air scattering. To my knowledge, in recent times experiments are (or are about to start) by F1AVY, VK4EBP , VE7SL and G3XBM (when fit again). I am sure there are others too. Weak signal modes certainly help. I used QRSS3 over an 8.5km NLOS path, but much further has been achieved.
 
See http://en.wikipedia.org/wiki/Non-line-of-sight_propagation .

A couple of useful optical Yahoo groups are:

Australian Optical DX   https://groups.yahoo.com/neo/groups/Optical_DX/info

UK Nanowaves              https://groups.yahoo.com/neo/groups/UKNanowaves/info  

10m WSPR DX

There was 10m DX to be had today. The first USA station to spot my 500mW WSPR signal was WG2Z (5600km) at 1216z. At the moment, the last USA station to spot me was K9AN (6505km).

Also spotting me earlier in the day were ZS6A,  ZS6DX and RI1ANR (13676km) in Antarctica.

UPDATE 2028z:   K9AN (6505km) was the last USA station to spot my 500mW  WSPR beacon today.

UPDATE 2032z:  I have now gone QRT on 10m WSPR. Another decent day on the most interesting of bands.