G4BAO.COM Microwave Amateur Radio Station, Waterbeach. 8km North Of Cambridge JO02cg
To Contact me: Skype johng4bao ON4KST Microwave Chat E-mail john at g4bao dot com QTHR Home About me  My Equipment  Projects  9cm PA pt 1 9cm PA pt 2 9cm PA pt 3 9cm PA pt 4 9cm TXvrter p1 9cm TXvrter p2 9cm TXvrter p3 9cm TXvrter p4  GB3CAM Andrew 23cm PA  modules Related links Downloads and Bodger's Guides	GB3CAM 24GHz beacon Allocated Frequency - 24048.870MHz GPSDO locked  Keying sequence is: Even numbered minutes. "GB3CAM IO92WI" in JT4G followed by "GB3CAM" in Morse  Odd numbered minutes. Unmodulated carrier until (minute +32 sec) then "GB3CAM" in Morse. Frequencies: Carrier                          24048.8700000MHz Keyup tone for CW       24048.8696000MHz JT4 tones Tone 0 24048.8697980MHz Tone 1  24048.8701130MHz Tone 2  24048.8704280MHz Tone 3  24048.8707430MHz Output power - 250mW Location - West Cambridgeshire,   IO92wi,   33m ASL Antenna - Horizontally polarised slotted waveguide at 31m AGL clover leaf pattern QTF approx 10dBi to SE/NW, 6 dBi SW/NW.      Introduction The idea for adding a 24GHz beacon to GB3CAM came out of some musings on the success of the 10GHz beacon. Mainly while cycling to work, in August 2007 and in a subsequent series of emails betwen myself, Bernie G4HJW and Sam G4DDK.  The idea came together very quickly as I already had a 12GHz multiplier, and Chris GW4DGU was keen to try out his design for a new ultra- stable  oscillator known as the "DISTAW". (pron. dish-tau) . Apparently distaw is a Welsh adjective meaning quiet or silent. So from concept to on air took just 13 months. It would have been 10 months if I'd not blown up two PAs in the process, but that's another story! The upgrade in May 2010 with GPS locking made it the first 24GHz beacon in the world to run JT4G (unless you know better)   GB3CAM Supporters Bernie, G4HJW - GB3CAM concept. Design, build and test of 3cm beacon. John,  G4BAO  -  24GHz beacon design build and test. Chris, GW4DGU - 24GHz beacon reference oscillator. Paul, G4AJE - Beacon site James G3RUH - GPSDO John G8ACE, Brian G4NNS, Andy G4JNT, - the Reverse DDS team    Ian, G8KQW, Brian G4NNS - 24GHz antenna build and test Phil, G8MLA - 24GHz PA Murray, G6JYB - Ofcom Liaison. Tom, G4TWJ - original 24GHz PA Sam, G4DDK - second 24GHz PA and moral support when things began to fail! Alan G3NYP -Connectors Dave WW2R/G4FRE  - original keyer   Ian G4AKD - Trial site for 3cm beacon The UK Microwave Group for financial support. The shutdown operators. G4HJW, G4BAO, G4BEL, M0BXT