Sunspots and 10m - May 21st 2015

Sunspot number has fallen to 61 today, but the K index is down to 1 indicating more stable conditions. 10m propagation is expected to be "poor" again today, although Es may well help liven up the band. I have already had lots of 10m spots by EA8BVP (2986km) by F2 and CT1JTQ (1843km) by Es. Just hoping for further afield, but this is probably less than likely. We'll have to wait and see.

160m indoor loft antenna

Some years ago G6ALB and I wanted a simple talkback link that we could use when co-operating on experiments. We were 3km apart with Andrew being in the next village. We immediately thought about simple AM rigs for topband (160m).

As I had no 160m antenna, I built the design linked here. This antenna works well with best WSPR spots being over 1000km.

We decided that topband was too noisy for our simple AM rigs for our intended purpose. The noise floor at both our locations is very high on 160m.  I have since moved QTH but we are still thinking about this link. We are now 3.3km apart. Probably 6m would be a better choice as less noisy and we both have vertical antennas.

See https://sites.google.com/site/g3xbmqrp3/antennas/160m_loft_ant .

10m WSPR - early spots by EA8BVP

EA8BVP (2986km) was spotting me early today, I presume this is F2 propagation. This is promising for the rest of the day, even though the 10m forecast is "poor". Otherwise just local G4IKZ (18km). No Es or GDX by tropo or aircraft seen yet, but it is very early.

UPDATE 1020z:   Apart from EA8BVP and G4IKZ, 10m WSPR is very quiet so far this morning.

UPDATE 1735z:  CT1JTQ (1843km) has been spotting me a lot of the afternoon. I think this was Es.

UPDATE  1940z:  F and OE spotting me on 10m WSPR. More Es.

6m WSPR this morning

I have been spotted by G8EPQ (77km) and have spotted G8EPQ as well and spotted G0OQK (98km) this morning on 6m WSPR.  As yet, no Es seen here but it is still very early. Both G8EPQ and G0OQK may have been aircraft reflection assisted I think.

UPDATE 1732z:   2E0BMG (62km) was spotted at 1600z.

UPDATE 2034z:  M0YOU (116km) was spotted at 2010z. The Doppler suggests aircraft involvement.

472kHz (630m) WSPR overnight

Late yesterday evening I changed from my "strapped feeders and loading coil" 630m antenna to the earth-electrode antenna that I'd been using all winter on MF. Spots on 472kHz (630m) WSPR  by G7NKS (46km) immediately jumped upwards by 6dB. This may be directionality, but results were definitely better.  I know my RX is deaf on 472kHz.  It tells me the "strapped feeder" antenna is not that brilliant!

Overnight the best DX was reception of DK7FC (669km) who is always a good signal and a spot by PE1RKT (285km). When I went back to the earth-electrode on 472kHz I resumed 10m WSPR beaconing but I was only copied by G4IKZ (18km) during the overnight period.

Now I am back on 6m (rather than 630m (472kHz)) and 10m WSPR.

Sunspots and 10m - May 20th 2015

Sunspot number is virtually unchanged at 84 (K=3) and 10m propagation is expected to be "poor". So far just local spots on 10m.

630m this evening?

In view of the dire conditions today on 6m and 10m, I am slightly tempted to try my QRP ERP on 472kHz WSPR (630m) this evening and overnight. Noise levels will be higher but it would be interesting to see if anyone copies me or if I copy anyone. I'll decide after tea.

At some point I want to try 136kHz again. I can run my QRP QRSS3 beacon into my earth-electrodes and go looking locally with my mag-mounted E-field probe. At the moment I don't feel fit enough though. From the old QTH I managed 250km on 137.5kHz WSPR. I need to make a better antenna for LF/MF at this QTH. I have space for a long wire with some vertical loading. Maybe in the autumn?

UPDATE 1852z:    Just returned to 472kHz (630m) WSPR using the strapped feeder of my Par 10/20/40m wire antenna tuned against ground with a loading coil. As yet, no reports given or received. Will stay on 630m late tonight and possibly overnight. QRT on 10m and 6m as I need the antenna (for 10m) and the PC and FT817.

UPDATE 1940z:  Still no spots given or received on 472kHz.  Since the winter there are fewer active stations it would appear.

UPDATE 1942z:  With only 10 active 472kHzWSPR stations shown as active in the entire world, I think I shall be pleased to get any spots in the log today.

UPDATE 2015z:  4 spots received from G7NKS (46km) are the only spots so far on 472kHz. Reports are within 1dB, so very consistent, if weak.

472kHz band WSPR spots by G7NKS this evening

Amateur VLF DXing

Operating an amateur station at VLF is a very specialised area of experimentation. There are basically 2 different threads (1) earth-mode or utilities assisted earth-mode with propagation mainly along or close to roads and (2) radiated DXing in which a VLF signal is actually radiated and propagated to great distances. With (1) I have managed 6km with QRSS3 with 5W from a TDA2003 audio IC at 8.97kHz. Earth-mode gear can be low powered and simple to build.

VLF amateur signals

With (2) the Atlantic Ocean has now been crossed, i.e. quite remarkable distances with amateur powers and antennas. Usually very large loading coils are needed and making these can be "challenging". As high voltages are likely, great care is needed. Of course, most DXing is done with very long stable transmissions in very narrow bandwidths. Most amateur VLF gear is home made with free PC software to allow signals to be seen. Casual listening is not effective.  Most operation is now around 8.300kHz as this is unallocated in many countries.

News of VLF activity may be found at https://sites.google.com/site/sub9khz/ .

6m tropo?

G8EPQ (77km) and I continue to exchange 6m WSPR spots today. Although there is evidence of aircraft reflection, this is probably mainly tropo at this range.   About 1Hz of the drift is due to my rig. When there is a large drift I suspect this is aircraft Doppler shift, so the dominant signal then (that being decoded) is via aircraft. So, probably tropo, but also via planes.

G4BRK (134km) was spotted on 6m WSPR yesterday but not seen him yet today.

Sunspots and 10m - Tuesday May 19th 2015

Sunspot number has dropped back to single figures standing at 83 today.  K=4 suggesting reasonably disturbed conditions. 10m is expected to be "poor" today. I am not expecting great things of 10m today, although some single hop F2 is possible and Es across Europe is always possible at this time of year.

UPDATE 0910z:  So far, the only 10m spots have been from local G4IKZ (18km). No 10m Es and no 10m F2 yet.

UPDATE 1046z:  Still just being spotted by local G4IKZ (18km) and nobody else on 10m.  I see the Southgate News is reporting a moderate geomagnetic storm.   See http://www.southgatearc.org/news/2015/may/geomagnetic_storm_on_may_19th.htm#.VVsVTkZQqPc .

UPDATE 1535z:  Still only G4IKZ (18km) spotting my 10m WSPR beacon. This is a bad day. Otherwise a total blank!

UPDATE 1600z:   K has reduced to 2 (was 4) suggesting conditions are improving. I wonder if we will see any DX this evening on 10m?

UPDATE 1755z:   Indeed a totally dire day, so far, on 10m WSPR with just local spots: no F2, no Es, nothing DXwise at all.