D-STAR Secret Nuclear Bunker

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George Smart, M1GEO has located a digital voice D-Star repeater at Keveldon Hatch sercet Nuclear Bunker. The repeater will provide coverage throughout west and central Essex, UK.

The site is located appx 30km northeast of London, and will be using the callsign GB7KH.

George was discussing the set-up of a Icom ID-RP4000V UHF repeater with ID-RP2C controller and Procom duplexer tuned for the output frequency of 439.6125 MHz and 430.6125 MHz input, during a recent Chelmsford Amateur Radio Society Skills Night.

George is currently trying to source 100 metres of LDF4-50 feeder, it's a long way to the antenna, he's also developing a remote control shutdown mechanism and sorting out the PC for the Icom G2 software.

Alongside the Icom repeater, he is working on a backup repeater which can be used in case of problems. This is a Simoco PRF10 series UHF repeater with DVRPTR_V1 GMSK modem, and G4KLX’s ircddbgateway and dstarrepeater software on a Raspberry Pi.

Further information on GB7KH - http://www.gb7kh.co.uk/

Chelmsford Amateur Radio Society Skills Night - http://www.essexham.co.uk/news/skills-night-feb-2015-report.html

Repeater Map - http://www.ukrepeater.net/my_repeater.php?id=2330

Make your own VHF or UHF transceiver

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Hans Van Rijsse PD0AC has released a website web page describing the Dorji DRA818 modules which enable you to make your own 1 watt VHF or UHF FM transceiver 

“Using these modules you can get a fully functional 1 Watt FM transceiver on either the 144 MHz or 430 MHz bands for under $13” Hans Van Rijsse PD0AC

Make your own transceiver with a Dorji DRA818U or DRA818V - 
https://hamgear.wordpress.com/2015/02/03/make-your-own-transceiver-with-a-dorji-dra818u-or-dra818v/

Dorji (Pdf) - http://www.dorji.com/docs/data/DRA818U.pdf

Klaus-Heinz Hirschelmann DJ7OO - Building Blocks for a simple VHF or UHF transceiver - http://tinyurl.com/Using-DRA818

Stunning Slow Scan TV from International Space Station

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Amateur / Ham Radio operators are continuing to receive fascinating images from the International Space Station.

“Receiving SSTV from the ISS really CAN be simple: For my first time ever, I simply fired up a $3 iOS app, and held my iPod touch near my Yaesu FT-60R’s speaker, and downloaded one of the images from the ISS.”
— Clint Bradford K6LCS

Twelve different images depicting space pioneer Yuri Gagarin - the first human to orbit Earth - are being sent on 145.800 MHz using the SSTV mode PD180, with a 3-minute off time between transmissions.

ISS.jpg

The transmitter on the ISS uses 5 kHz deviation FM. If your rig has selectable FM filters (most mobiles do) make sure you choose the wider setting designed for 20 or 25 kHz channel spacing, usually marked FM or FMW.

Images received so far by radio amateurs worldwide - http://www.spaceflightsoftware.com/ARISS_SSTV/ 

Find out more about receiving these transmissions and links to decoding software - http://amsat-uk.org/2015/02/11/more-iss-slow-scan-tv/

The transmitter on the ISS uses 5 kHz deviation FM. If your rig has selectable FM filters (most mobiles do) make sure you choose the wider setting designed for 20 or 25 kHz channel spacing, usually marked FM or FMW.

Images received so far by radio amateurs worldwide - http://www.spaceflightsoftware.com/ARISS_SSTV/ 

Find out more about receiving these transmissions and links to decoding software - http://amsat-uk.org/2015/02/11/more-iss-slow-scan-tv/