31 Oct 2009

500kHz - two new reports and a new country

M0DUO (104kms away) spotted my 500kHz WSPR beacon late this evening. Then in the middle of the night my first report from The Netherlands from PA3FNY (JO22nc at 330kms). So, 22 different reports in 11 grid squares and 5 countries with best DX remaining 896kms. Not bad for a 6m long antenna and less than 1mW ERP!

AA1TJ's Code Talker TX

Mike Rainey has now added a schematic to his page on the New England Code Talker CW transmitter powered and keyed only by audio derived from his whistling into a loudspeaker. Mike is hoping to span the Atlantic with a similar TX on one of the HF bands in the years to come, knowing that others have "crossed the pond" with powers as low as 1mW or less when conditions were very good.

LC Meter - a nice kit

Some months ago I bought a PIC based LC meter kit from the Cambridge Radio Club (CDARC). This was a club project and the unit allows very accurate measurements. The kit had remained unbuilt until today when I decided to build it. I'm impressed: it went together well and worked first time. The quality of the kit is first class with a custom case, silk screened PCB and good instructions on the club website. This little box will measure from low pF and nH right through to uF and mH. I can see it being used almost daily. I believe CDARC is to make these kits available more widely. Go and buy one for £50.

20th station hears me on 500kHz

Last night M0WKR (IO94 at 237kms) reported my 500kHz WSPR beacon bringing the total number of unique reporters up to twenty.

30 Oct 2009

The 500kHz ATU

This is a close up picture of my 500kHz ATU which consists of a ferrite rod with thin copper wire tapped at various points to which the antenna and TX are connected. The TX connection is about 5t from the ground end. Also in view are the current transformer (the small toroid with 50 turns secondary) and the small meter used to measure the antenna current.

AA1TJ's "Code Talker TX" - all voice powered

Mike Rainey continues his work on purely voice powered transmitters, in which just the energy in his voice is used to power the RF circuits i.e. no batteries or PSUs at all. He's achieved well over 100kms on 80m this way using a form of CW derived by whistling into a loudspeaker to generate the energy needed. Here is an example of his signal received 109kms away. He can clearly be heard "keying" (actually whistling!) the words of "Mary had a little lamb" in CW.

29 Oct 2009

A good evening on 500kHz QRPp

This evening my 500kHz WSPR beacon has been running from 1700-2300z, still with less than 1mW ERP. As the map shows, this is not preventing 8 stations in 4 countries copying me and many at considerable distance. There has been some transatlantic propagation this evening with SM6BHZ and OR7T being copied in Canada already. These are distances I can only dream of with my tiny station!

A 19th reporter on 500kHz

G4EFE managed to hear my WSPR beacon on 500kHz several times last evening (127kms) bringing the total number of unique stations receiving me to 19 now. I still have work to do to get over the 1000kms distance target.

26 Oct 2009

500kHz - an 18th station hearing me

This morning at around 0930z I received a new report for my 500kHz WSPR beacon, this time from G0HNW who is 200kms away. This brings the total number of reporters to 18. 16 were via the WSPR database and a couple of others via the RSGB LF reflector. Clemens DL4RAJ has been looking for my signal for many nights but thinks I need a further 10dB of ERP before I reach central Europe.

25 Oct 2009

CQWW contest summary - 10m was great

With darkness falling now 10m is going quiet after an exciting 2 days. In the end, my 5W SSB and halo antenna worked 35 stations in 20 countries. DX from outside Europe was not workable this time but I was hearing CX, PY, ZS, 6W, etc so conditions were definitely not bad. Although there were a couple of stateside stations worked from Europe, I did not manage to hear them. The slight upturn in sunspot activity came just at the right time.