Linux Journal - special ham radio edition

The January 2010 edition of this US Linux OS magazine is a special one dedicated to amateur radio. Although I'm not a Linux freak, I'm sure that many readers will find it of interest.

See http://www.linuxjournal.com/ham

500kHz transverter boxed at last

Today I completed the 500kHz transverter by putting it in a small Maplin's ABS case with coax connectors and an on/off switch. Attached is a photo showing the transverter unit on the shack table and with the box lid open so you can see the completed unit. It has been a most enjoyable project. The schematic of the transverter is on my website on the "Operating on 500kHz" page.

On WSPR, I'm still awaiting my 50th unique report that I hope will come in the next few days before I take down the 500kHz antenna and reinstall my 28MHz halo.

Big Ben - a 119 year old recording

Not ham radio, but just spotted this fascinating recording of Big Ben chiming. It was made on a wax disc 119 years ago in 1890.

Geminids meteor shower tonight

This evening the Geminids meteor shower should peak between 2000 and 2200z in the UK.  As there is no moon visible and the sky should be reasonably clear it could be a fine sight. Increased meteor activity should allow European DX on bands like 50MHz and 144MHz by meteor scatter (MS). Best place to listen/look is on 50.230MHz in JT6m mode.

YO5OFJ's pages with everything

Vanyi's Homemade/homebrew HF transceivers page is a collection of lots and lots of circuit ideas showing transceivers from 160m - 10m created by various people over the years. It is a good place to look for ideas when thinking about new projects.

DSB mod for the Heathkit HW8

When looking around for ideas for DSB rigs I found a page which shows how to modify the HW8 for DSB operation by adding a balanced modulator and audio stages.  KL7R reports that he worked New Zealand using the modified HW8 on sideband.

Received in Norway on 500kHz

Last night, a couple of LA stations were listening on 500kHz WSPR. Neither had heard my 1mW QRP signal by 2300z, so I left the station running through the night. At 0418z LA9BEA heard my signal at -28dB S/N in JO29 square some 836kms to the north east of me. This is now my 8th country, and 49th station, to log me on the band.

NMRevue Magazine (from Belgium)

Just found a link which takes you to back numbers of the NMRevue magazine from Belgium. I'm not sure if this is a club/regional magazine or a national magazine, but it does have quite a few nice constructional articles in each issue. Unfortunately you will need to read French to fully enjoy this.

Rising sea levels - what would happen?

Whatever your views on the causes of climate change, it is a FACT that the Earth is currently warming and sea levels are rising. This interactive map allows you to put in the likely sea level rise, in 1m steps, to see how the coastline would change. Some places are little changed but others are e.g. The Netherlands and the Fens in the UK.

A draft text for an agreement on climate change reduction has been released today in Copenhagen. It needs a lot of work.

Classic 10m DSB TX

There was an article, in 73 Magazine back in the early 1970s, about a simple crystal controlled, 1W 10m DSB transmitter. This was reprinted in a Dutch magazine and in RadCom. The schematic had at least one error (one diode in the mixer wrong way around, that I have corrected here), but it is a useful "ideas" starting point for a DSB transceiver. This circuit used PNP transistors. Today I'd use NPN 2N3904 devices and T37-6 toroids everywhere.