some thoughts a cool project interface a text to ham radio user goes to google voice, sends a text to a specific number that number translates the text to morse code and sends it out on the air then it listens on those frequencies for replies, translates them backand sends them to the google voice number. how cool is that? talk about field day! ---------- imagine a box A held by person A and a box B held by person B box A will be the initiator and box B will be the respondent. box B is in listening mode box A (when turned on by person A?) sends a message the message contains an arbitrary time code TA1 produced by a high frequency oscillator and pulse counter TA1 stands for Time Code produced by A message 1 (oscillator and pulse counter described separately) box B on receiving the message responds with a message TB1 containing its time code. as soon as box A sends its message it switches to listen as soon as box B receives A's message it transmits a response then switches to listen A displays sent null recv null B displays sent null recv null On START command from person A A recvs START and sends TA1 (46) and displays sent TA1 (46) recv null B recvs TA1 (46) and sends TB1 (17) and displays sent TB1 (17) recv TA1 (46) A recvs TB1 (17) and sends TA2 (52) and displays sent TA2 (52) recv TB1 (17) B recvs TA2 (52) and sends TB2 (20) and displays sent TB2 (20) recv TA2 (52) ------------- digitizing remote radios and then sending the results back is a huge bandwidth hog, not to mention processing. so its best to relay the content back as analog RF and then use "lazy evaluation" or in this case, "lazy digitization" of the signal at the final base station. The three transmit frequencies are: 1) TX: 216.983 MHz 2) AZ: 216.970 MHz 3) AL: 216.990 MHz None of these are in the ham band, although they sit closest to the 1.25 meter (222 MHz) band, which spans 219 - 220 MHz and 222 - 225 MHz So one could adapt 1.25 meter receivers for this band for listening to NAVVASPUR signals (action item, do the FFT of a NAVVASPUR crossing) The Space Fence is scheduled to be replaced in 2015 and replaced with S band radar. S-band radar spans the frequencies from 2-4 GHz. Amateur bands range from 2.30 - 2.31 MHz 2.39 - 2.45 MHz 3.30 - 3.50 MHz For now one can listen to the three space fence frequencies (TSFF) and they could be retransmitted in the 70 cm band (420 MHz) since it spans 420 - 450 MHz and the doubled frequency is just 434 MHz, right in the middel of the 70 cm band. No halving of the TSFF fits into amateur radio bands. so the task is, listen for events on the three 217 bands starting with TX amplify, mark with GPS time code, double the frequency, transmit to the common base station at 434 MHz receive, combine, coreggister and determine time differences ----- repeaters cannot be used since they demodulate down to audio, which destroys all accurate timing information. ------ so need a mixer to add the GPS carrier and a frequency doubler to place the signal in the 70 cm 434 Mhz band. 1.25 m to 70 cm transverter 222 MHz to 434 MHz transverter listen, mix, double, transmit (LMDT) OR listen, double, mix, transmit (LDMT)