Category Archives: Uncategorized

Portable ex-military HF at Reading Rugby Club

A few quick snaps taken of our members Michael M0MPM, Harry G3NGX and Jim G0LHZ enjoying a play with some man-portable vintage ex-military gear. With one of the radios dating back to WWII, and with the split frequency operating figured out, at least one legitimate QSO was had, with good reports both ways. With the solar cycle in full swing a new DX record was set, with a mighty 0.2km achieved across the front of the rugby club.

With thanks to our members for supplying the pictures.

Michael M0MPM/P

Harry G3NGX/P

Jim G0LHZ/P

“ACE HIGH” Tropo Scatter system

While researching for club talks, I ran across the following link regarding the tropo scatter system used in the 1970s/1980s with eye watering ERPs. A few members will know about this system, however many new to the club may not:

https://www.subbrit.org.uk/features/ace-high-nato-communications-system

Like Graham, G3XYX I have visited the Stenigot site in Lincolnshire wolds (in itself an incredibly beautiful place) – sadly only one dish remains now. Possible club talk if anyone knows a speaker…?

RADARC 85th Year Celbrations – June 15th 2019

Dear Members,
RADARC is pleased to announce that we are holding an 85th year celebration at the Royal Oak, Knowl Hill RG10 9YE on Saturday 15th June 2019 We will be setting up a small station/display in the field at the back from 11:30am, and from that point onwards you are very welcome to join in informally, have a pint etc.
At 18:00 there will be a barbeque @ £5 per head. If you wish to just come along just for this that is of course fine.

The Royal Oak is a nice traditional pub in a beautiful location, so it should be fun. Lets hope the weather is kind as well.
If you are intending to join us for the barbecue, please let me know so that I can give the Royal Oak an idea of numbers.
Looking forward to seeing you there.
Thanks and 73 Simon M0ZSU, RADARC

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Operating on QO-100

Heard of QO-100? Also known as Es’hail 2, the first geostationary satellite carrying amateur radio transponders launched from Kennedy Space Center at 20:46 GMT on Thursday, November 15, 2018 and is now in a geostationary orbit at 25.9° East. These are the first amateur radio transponders to be put into geostationary orbit and the satellite footprint covers an area from Brazil to Thailand. The transponders are very wideband indeed, and have been designed to be relatively straightforward to access. Being a wide linear transponder, there’s plenty of room, but also plenty of activity, and the activity is in all sorts of modes, including digital ATV, digital voice, CW and SSB. The downlink is 10GHz and the uplink is 2.4GHz. These frequencies are no coincidence…

Receiving QO-100 is a matter of connecting an inexpensive commercial LNB, like you’d find on the arm of any Sky dish, to a suitable power supply via a bias-T, to an inexpensive SDR connected to your PC, including the RTL USB dongles, or indeed to any wideband multi-mode receiver that covers 7-800MHz. An unused Sky installation could be used pretty much as-is, by simply tweaking the dish to point to a very slightly different point in the sky – 25.9°. Indeed there are reports of QO-100 being heard via Sky dishes while the dish is still aligned on the Sky constellation at 28.2°E. PLL-equipped LNBs are better, but not essential.

Once you have a receiving setup sorted, it’s time to turn your attention to the transmitting side. The uplink is in the 13cm amateur allocation, adjacent to 2.4GHz Wi-Fi. There is a lot of room for creativity here, and lots of options. OE5HSR has pulled together an excellent PDF, which is pretty much a must-read for this topic. You can find this here.

I’m sure that some of our members will be having a go at working this unique satellite, and if you’re one of them, we’d absolutely love to hear from you at one of our show-and-tell evenings, or even better a live demo!

72000km+ SSB QSOs using a couple of watts and some recycled gear? Yes please!

Credit: AMSAT-UK for orbital and footprint information