AM and UK Band Plans

Because of my poor voice (as a result of my cerebellum brain bleed) I tend to use digital techniques, like WSPR and JT65, but I still enjoy AM.  Like many, I've worked transatlantic AMers on 29-29.1MHz with real QRP and simple antennas using AM. It makes a great change from SSB.

One could be forgiven for thinking AM is a dirty word at the RSGB.  In UK Band Plans published in the February 2015 edition of RadCom, AM gets no mention on 28MHz and 50MHz and gets a (begrudging) comment as a footnote only in the 144MHz Band Plan when other modes get "centres of activity" mentions. AM is alive and well in the 29-29.1MHz sub-band. AM on the 144MHz (2m) band here in the UK can be found on and around 144.550MHz. There has been AM on 29-29.1MHz for years and years and years - in fact almost as long as I've been active on the air. Yes, this is in the all-mode section, but why not say this is the 28MHz (10m) AM sub-band? Also, why are 144MHz AM users asked to "consider adjacent channel activity"? AM should easily fit in 6kHz!!

Yet again, AM is being treated as a dirty and outdated mode. Here in the UK, ex-PMR AM rigs ripe for use on VHF can be picked up for virtually nothing and there is certainly room for AM on all bands from 28MHz upwards. AM has its enthusiasts on other bands too, but yet again the RSGB seems keen to kill off this mode. Why I wonder?

Allegedly, a RadCom article on digital TV in the 146-147MHz band was pulled last month at the last minute because "someone at the RSGB" thought it would not fit in the new band! Sometimes one wonders. Maybe the day when I only get SPRAT is closer than I thought? Thankfully, there are many good articles in RadCom.

10m USA WSPR spots

The first USA spot of my 500mW 10m WSPR beacon was at 1240z today by WG2Z (5600km). All morning I was being spotted by EU stations and 4X1RF (3519km) but no further.

Apart from one day, the 10m band has been open here to the USA every day since the early autumn.

UPDATE 2040z:  My last USA 10m WSPR spot today was by K9AN (6505km) at 1858z.

10m 3 transistor DSB transceiver

In case you missed this:

http://www.cqpub.co.jp/hanbai/books/15/15061/15061_p.180-181.pdf

This gives the schematic and lots of data in Japanese.

All RF circuit inductors could be replaced by small  (T50-6 or T37-6) yellow toroids and variable caps.

Sunspot number - Jan 21st 2015

Sunspot number today has risen slightly to 57.  10m propagation is expected to be "fair". Already being spotted by 4X1RF (3519km) on 10m WSPR with my 500mW 10m beacon.

10m 3 transistor DSB rig video, and more on the Minima

Stephen G7BFY sent me a link to a video on YouTube of the Japanese 3 transistor DSB transceiver featured in this blog some years ago. It is being tested by some Italian stations over a 10km path. Sorry this video is in Italian.

See https://www.youtube.com/watch?v=PqpfLSqtVgs

Minima Video
The video below is of the Minima SSB/CW transceiver. The transceiver is towards the end of the (rather noisy) video. This is the creator, Ashaar Farhan, in the (Indian?) video.

 

472kHz WSPR

All day and overnight I have been on 472kHz WSPR using 5mW ERP from my earth-electrode "antenna". Although I have been copied by no new users in recent weeks, I have been spotted by G4JVF (151km) and G8HUH (250km) amongst others today. My best DX on TX with the earth-electrodes is 722km.

On RX I am consistently copying PA stations at over 400km. Although people tell me there is less WSPR activity on the band lately, I never fail to spot, or be spotted, on this MF band even with my compromise antenna and very low ERP.

160m/80m DC transceiver

These are bands I rarely use, but some readers may be interested in the Hendricks Kits dual band transceiver. 5.5W sounds enough to work plenty.

These days, the main issue on these bands can be man-made noise from TVs, SMPUs and similar. At my old QTH I had an S7-8 noise floor on 160m and 80m. At the new QTH the noise floor on these bands is low currently, but this could change overnight. Some people use loops and nullers on RX to minimise problems. If you have a quiet noise environment then this transceiver may fit your needs. Don't forget you will need a reasonably big antenna to get decent results. A half wave 160m dipole antenna is around 240 feet long.

In my youth we had rigs like the Codar AT5 12W AM/CW 160m/80m transmitter and companion T28 RX. I had the RX but not the TX although I did use an AT5 from the QTH of the late G4PJ. The T28 was mainly used as a tunable IF for my 2m converter. I heard my first 2m satellite signals via Oscar 6 and 7 using the T28 as a tunable IF. I remember being very thrilled hearing my first transatlantic stations on the top end of 2m.

See http://www.qrpkits.com/mbdc.html .

Last 10m WSPR spot today

W3CSW (5886km) was the last USA station to spot my 500mW 10m WSPR beacon today at 1658z. I guess the last 10m spot depends on several factors: propagation/conditions, daylight on the path, active stations etc. Last night the I was getting spots later.

First 10m WSPR spot today (500mW beacon) from the USA

N1NCO (5283km) was the first USA station to spot my 500mW WSPR beacon on 10m today at 1238z. Several EU spot this morning plus 4X1RF (3519km) who often spots me. This is Asia.

Sunspots

Sunspot number today is 62 and 10m propagation is expected to be "fair" . Just turned on the 500mW 10m WSPR beacon at 0945z.Already LZ1OI (2153km) is spotting me well.