18 Feb 2014

Transformer success on 474.2kHz

This afternoon I inserted a small 3C90 cored transformer between the transverter and loading coil on the 15m earth-electrode antenna. Much to my surprise the best performance (25% increase in antenna current was with a step-up from 4t to 14t implying the earth electrodes look  like several hundred ohms. Success was immediate with a first spot from M0JXM (93km) and report from G3WCB (101km) some 3dB stronger at -18dB S/N. The loading coil today (soil less damp outside?) is around 50-100uH only. The transverter runs cool implying a good match.

17 Feb 2014

More 474.2kHz WSPR success

Overnight my transmissions with the 15m baseline earth-electrode antenna continued. A couple of  reports from Holland were added to the list of spots bringing the total UNIQUE station reports to eight. The only change has been to resonate the loop with a small series inductor. This increased the loop current by about 20%.  Next to try will be to see if the 50 ohm match can be bettered with a small auto-transformer. I suspect not, but we'll see.
UNIQUE reports received on 15m baseline earth-electrode antenna on 474.2kHz WSPR




16 Feb 2014

Easily tired - stroke

One effect of my recent stroke is I get exhausted very quickly.

Sitting on the PC is OK, apart from having to correct all my typos,but anything involving physical work, or talking, rapidly tires me. As an example, today is a beautiful sunny day (8-10deg C),  so a good chance to prune some roses in the garden, except that after doing a couple I was exhausted and just had to rest! This is not the real me at all!

Even talking on our local 2m net on Monday's tires me: it is speaking that tires me the most. At least with WSPR, once set up, operating does not tire me. It runs itself and all I have to do is check all is OK and observe results on WSPRnet.

The other day I wound a 400uH coil,with taps, on a 110mm drainpipe for 472kHz ,but the effort needed was so tiring. At the moment, major build projects are out of the question until my strength and stamina return.

I do so want to get better and be back to my normal healthy self.

474.2kHz WSPR results - 15m earth-electrode baseline

I left 474.2kHz WSPR running overnight using the 15m baseline earth-electrode running vaguely E-W. Results were encouraging. Don't anyone say they can't erect an antenna for 474.2kHz! If even THIS works, almost anything is possible.
474.2kHz UNIQUE WSPR spots in last 24 hrs on
15m baseline earth-electrode "antenna"
Some stations are actually stronger on the earth-electrodes than on the conventional "wire in the air". Best DX 701km with an ERP around 5mW MAX and no conventional antenna is not at all bad. I am sure a proper Marconi antenna would be better but the earth-electrode ground "antenna" is a good compromise system when options are limited. It is totally invisible too - VERY neighbour friendly.

On the receive side, 10 unique stations copied in 4 countries. Not bad for a less than 24 hr period.
474.2kHz UNIQUE WSPR spots in last 24 hrs on 
15m earth-electrode baseline on receive

15 Feb 2014

Proposed new 474.2kHz Earth-electrode baseline

The yellow line shows the approximate 15m baseline used currently on MF WSPR.
The red line shows the proposed new earth-electrode baseline which should place the northern electrode well clear of buried pipes and wires. It should be better, but you can never be sure until you try it! I (or a friend) need to hammer in some new ground rods first at either end of the baseline wire.

Back on 474.2kHz TX

Partly as a result of damage to the Par HF antenna, I decided this morning to connect my earth electrode antenna on 474.2kHz and TRANSMIT for the first time in around 6 months. It works OK, although the baseline will be extended later. with spots exchanged with G4KPX (Ely), G3WCB (101km) and G6AVK(78km) at sensible levels. It will be interesting to see the results this evening with some sky wave. UPDATE 2230z: No sky wave reception reports yet received.

For reasons I don't understand, I have received NO reports of my signal since 1550z. I have rebooted the PC, reloaded the WSPR software,changed frequency (several times),  checked internet time synchronisation, checked antenna current, checked just about EVERYTHING.  Received signal levels of other stations are as before. The only change is it has been raining. A puzzle as if the earth-electrode was behaving differently I would have expected changes to antenna current and received signal strength. I'll leave everything running to see what happens. Or is it just that my weak signal is being clouded out by higher band noise as afternoon becomes night? I'd still expect to receive some reports, especially considering how good some stations are on RX.

Eventually I got a -31dB S/N (just copied) report at 2034z from M0EMM in IO82sq at 192km. Shortly afterwards I was copied at -23/-24dB S/N by G3WCB (101km) several times.

Maybe it IS that my signal is right down in the noise for most people a lot of the time?  If so, significantly lengthening the earth-electrode baseline is a priority (see next post).

These are the unique reports so far on the short baseline earth-electrode system up until 2150z this evening.All stations reported me many times:



Par 10/20/40m antenna - storm damage

Looking out of the window I see my Par HF antenna has come apart and is dangling on the back lawn.  I shall be unable to re-erect it until my son next visits.  In the past (before my stroke) I would have had it fixed in 5 minutes! A quick trip up a ladder. I now have to be patient.  It looks like it has broken at the 40m trap, so should be easy to mend.

GB3VHF - storm damaged?

See http://www.gb3vhf.co.uk/GB3VHFservicenewsannouncements.html .. GB3VHF was off air 0900 on Sat Feb 15th due to suspected damage in the recent storms. The outage is being investigated. This is a well used beacon normally.

14 Feb 2014

10m Band Plan - some movement?

The RSGB is seeking views on band plans currently via their website forums (hard to navigate to in my opinion) and the outputs will go to the IARU later this year.

One possible recommendation is the extension of the wider band mode section on 10m from 29.1MHz down to 29MHz. 29 to 29.2MHz is the well used 10m AM sub-band, but changing the bandwidth allowed 29-29.1MHz (i.e no longer 2.7kHz) would mark a great advance over the current confused status of AM on 10m. It would be nice to have the words AM in the bandplan, but this is, sadly, unlikely. As I said before, it would appear the RSGB and IARU believe AM is a dead mode - if only they would actually listen 29 to 29.2MHz in a band opening.

If you have views, please share them on the RSGB's website.

This was John G3WKL's email pointing me to the right place on the RSGB's site. It is not exactly easy to find. The RSGB needs to make this easier if it wants peoples' comments! :

"Roger,

The relevant consultation topic is at
but if you are not registered for this new “forum” application it would be better to go in via
as that gives you the “register” link.

You’ll see that Ian has picked up on our earlier discussion concerning 29.1 MHz but you are welcome to post further comments.  Suggestions for new HF topics should be put in
and VHF matters in the appropriate topic under “C5 – VHF/microwave Matters”

73 John, G3WKL"

13 Feb 2014

IC703 and FT817 Mk II

Some years ago I sold my mint 10W IC703 (with 50MHz and auto ATU) to a local ham at well below market price. Without doubt, the IC703 is an excellent radio and an ideal main station rig for QRPers and Foundation licence holders. Power can be turned down to 500mW or up to 10W. There was a PA design fault that was corrected on my radio.  The DSP does a credible job as does the TX RF based speech processor. The IC703 is no longer being made.

I sold it as I have an FT817 that gets well used and basically does all I want, but I do regret selling then IC703 really. If I had my time again I would still be owning the unit, but it IS getting well used with the fellow ham locally. Before he was stuck with just 1-2W on 20m.
http://www.mclnet.org/on3zl/images/ic703_front_big.jpg
See https://sites.google.com/site/g3xbmqrp3/hf/ic703 for more about this rig. In my view, the internal ATU matches lots of different antennas. It really is a pretty well self-contained radio apart from the external battery or PSU.

All I want is for Yaesu to do an FT817 Mk II with a similar spec and internal battery pack but this now seems unlikely any time soon.