10 Jan 2014

6m GDX?

I get G8EPA consistently at 61km on 6m WSPR at up to -15dB S/N. This rather suggests that >100km should be possible inter-G on QRP 6m WSPR with a little patience. Anyone out there willing to give it a try?

10m 134km GDX tests this evening

This evening G3WKW and I are trying to span 134km on 28MHz WSPR. I run 2W to a vertical and Bob runs a little more.  Despite Doppler and rig drift problems we managed the path (just) on 144MHz this week.  28MHz may be much weaker but with far less Doppler and rig drift. We shall see. With WSPR about 12-14dB better than CW we have the best chance.

UPDATE 2200z: Nothing at all seen since 1816 (USA) and 1824z (Es).  Will keep looking but not hopeful. No GDX seen at all.

9 Jan 2014

Chinese QRP transceivers

In my recent analysis of good value QRP radios I ignored the recent Chinese entries into the market. As far as I can see, these are still immature products, but they are getting better by the day. For example, see http://www.wouxun.us/item.php?item_id=302 . I judge this by how prepared would I be to buy a Chinese radio. The answer is not yet.

10m still brilliant

As 6m WSPR was only giving me inter-G signals today, I switched to 10m. The band is still wide open to North America and has been whenever I have checked in recent afternoons. Not one report  is from less than 5000km with 2W. Sunspot count is 178 which helps to explain the good conditions of late.  The good times will not last: make the most of them as it may be a long wait.

At 1716z the 10m band was still wide open to the USA, in total darkness here.Then the band just died for me here in East Cambridgeshire. And then, a full hour later KB9AMG (6300km away) and W8AC spot me at -22dB S/N. And it has been dark here since 1630z! At the moment it looks as if the band finally died cross-pond at around 1830z -very late for 10m.











Micro-40 DSB build

http://aa7ee.wordpress.com/2013/10/19/the-vk3ye-micro-40-dsb-transceiver/ has a beautiful description of the building of this little transceiver using Me-squares. There is  a complete walk-through of AA7EE's build - truly beautiful workmanship.

6m and 2m inter-G WSPR

Although inter-G DX is possible on 2m WSPR (witness the tests between G3XBM and G3WKW over a 134km path on 2m recently with 2W and a halo) the equipment drift and Doppler shift makes WSPR a marginal mode on 2m. Things on 6m are better and longish paths are possible.See the 6m WSPR results today so far below:

So far, only inter-G paths seem to be open on 6m today. The high drift figures are almost certainly due to aircraft Doppler.

8 Jan 2014

Best value new QRP transenceivers

At  the moment the running order, ignoring wSDR designs, is:
  • Elecraft KX3  - best RX, expensive with all options in the UK. n ternal auto-ATU option
  • Ten-Tec Argonaut VI - excellent RX and ideal base station but no  5,24 or 50MHz coverage.Expensive.
  • Yaesu FT817ND - excellent base/portable unit up to 432MHz,but RX not as good as KX3 or Argonaut VI. 13-14 year old design.
  • Icom IC703 - excellent base transceiver,but no longer available new. Internal auto-ATU.
Overall, the FT817ND represents best value for money all things considered, in my view. It may be an old design but I can buy 2 FT817ND with plenty of change for the price of the KX3. And I get a better design for home station digital (WSPR) use with botj 144 + 432MHz bands. Even adding a Z817 or T1 auto-ATU to the price of the FT817ND units there is still change when compared with the fully loaded KX3.

Reviews on www.eham.net are similar for all radios listed.

10m still wide open

My first 10m WSPR transmission with 2W to a small antenna after lunch was copied in the  middle of the USA, in Canada, Israel and South Africa. Sunspot count today is 196. Conditions appear to be very good  still.

Oscilloscope-watch

John Mullin sent me this link which may amuse you.It describes a wrist wearable scope and frequency counter for $150.

http://www.ae5x.com/blog/2014/01/07/an-oscilloscopefreq-counter-on-your-wrist

7 Jan 2014

First 2m WSPR results

This evening I got my first WSPR spot on 2m from G3WKW at 134km the other side of London in North East Hampshire. It was hard work with the unmodified FT817 because of frequency error,  drift, Doppler etc. Bob was visible with me but no decodes of his signal.

We should manage a 2-way QSO in due course with a more suitable mode. I was using 2W to a halo antenna. Bob was using 5W and a small beam.

The  next night I managed to decode Bob's signal (once only) although he was visible on most transmissions  but not decoding because of the Doppler shift.

NB post updated as I had G3WKW in the wrong county!