Sunspots and 10m - Fri April 8th 2016

Solar flux is 93 today (rising) and the sunspot number is 26 (K=2). The forecast for 10m propagation is again "poor". Today could be another disappointing day?

Late start on 10m WSPR today

As we have grandchildren with us, I was late starting 10m WSPR today. I eventually started just before lunchtime.

Google changes to blog address - NOT amateur radio

To get to my blogs you may have to change the URL. See the following from Google:

Coming in late April!
All visitors will be able to view your Blogspot domain blogs over an encrypted connection by visiting https://.blogspot.com. Existing links and bookmarks to your blogs will continue to work. As part of this change, the HTTPS Availability setting will disappear, and your blogs will always have an HTTPS version.

10m short-skip

It looks like the Es season is nearly here on 10m. Today there was just one spot from OE6PWD (1232km). These are the spots so far.

RSGB and the EMC Committee

See http://rsgb.org/main/about-us/committees/electromagnetic-compatibility-committee/ .

Having just read the latest minutes, my negative views on OFCOM have been re-enforced. They seem to want to do very little about real EMC issues. I quote:

"JR reported that Ofcom had said that the WTA s54 Regulations, consulted on a year ago, would be published very soon. Although very welcome, if they only covered a narrow definition of “apparatus” in EMCD terms, that would leave a major hole in their scope. We would need to examine them carefully and consider how to respond. Ofcom were to have an article about the Regulations in RadCom. Ofcom said they were setting three conditions to act under the Regs. 

1. Harmful interference needed to be demonstrated; 
2.  All reasonable steps had to be taken to reduce/alleviate the interference at the receiver; 
3. There had to be a realistic prospect of an outcome. "

Full marks to the RSGB for continuing to challenge OFCOM.

OFCOM bureaucrats - do your jobs or go! There is zero space these days for quangos that do not add value. I have heard the arguments in support of OFCOM, but in all recent dealings with them I have not been at all impressed. Yes, they may bleat "lack of resources", but fewer bureaucrats and more engineers in the field would be a good start.

The virtues of QRP

As you know only too well, I love QRP.  No TVI, no noisy fans, low electricity bills, etc.. Yes there are times when more power helps - this I do understand. However, most contacts at QRP levels are fun, and this is something that I enjoy.

Our hobby is such that it can be enjoyed in many different ways: if you chose to run 1kW and a beam and rag-chew, that is fine by me. If you like satellites that is fine too. All I am saying is QRP is fun. Two-way QRP is even more rewarding, especially if some of the gear is home made. I like 472kHz as my transverter was designed and built by me. Details are on my website at www.g3xbm.co.uk .

Over the years I have managed well over 100 DXCC countries with QRP SSB. Others have worked far more countries than me. I hope this does not sound boastful: it is intended to encourage others.  Even in the worst years of solar cycles N--S paths are sometimes workable with QRP SSB on 10m.

If you think high power is necessary, may I invite you to turn the power down to 5W?  You may be surprised by what you can still work, even with SSB.

Sunspots and 10m - Thurs April 7th 2016

Solar flux is 88 but sunspot number is just 13 (K=1) and the forecast for 10m propagation is yet again "poor". I have been on 10m WSPR for about 30 minutes.

UPDATE 1135z:  No spots, as yet, on 10m WSPR today.

Best ever TX DX (5mW ERP) on 472kHz WSPR from this QTH

Last night, I was spotted by LA9IY (1393km) for my best ever TX DX from this QTH on 472kHz WSPR . In all, 10 different stations received me last night on 472kHz WSPR. As usual, I am still using the earth-electrode "antenna" in the ground. Performance amazes me.

Yet again, this proves you do not need lots of power or big antennas on this band. Simple works. QRP rules!

AM and AM Modulation

Someone suggested I put this on my blog, so here goes with a brief introduction.

My favorite method is series modulation using a transistor as the "modulation" stage. The modulated RF stage is set so the stage voltage is close to half rail. With modulation the voltage swings to close to full rail (4 times the power). This stage is followed by a linear amplifier to bring the power up to that required.  I used this in my Fredbox and Sixbox rigs without a linear. If I ever do a simple Tenbox AM rig I'd add a linear RF stage.

See Fredbox .
See Sixbox .

Don't forget that if you click on a picture or schematic on my website a larger version is usually available.

AM rigs are simple to build. I am truly surprised that these have gone out of favour in recent times. Surplus PMR AM rigs can often be found for almost nothing.  Back in the 1950s and 1960s AM was the predominant mode on HF and VHF.

There is plenty of space for AM on 10m, 6m, 4m and 2m. A decent AM rig should only occupy 6kHz or less of bandwidth.

D-star Cubesat

Southgate Amateur Radio News has a report today of a D-star transponder on a Cubesat. I ahve to admit that I am not "turned on" by these digital modes. It seems to me we are in for a standards war in the coming years. I am happy to sit this one out until the punters decide on one. System fusion, C4FM, D-star, DMR?? Others? Who cares!

See http://www.southgatearc.org/news/2016/april/dstar_satellite_to_launch_from_kourou.htm#.VwTc_L6LWzk.