Satgen242 Simply Dove by GM4IHJ 13th Nov 93 BID of this msg is SGEN242 Please use this BID if you retransmit this msg As most readers will know, a superb effort by several US Amateurs has brought the Dove Educational Satellite back to life. At the moment it is still being checked out, but it is transmiting excellent science data every 100 minutes or so as it passes UK. It signal comes down strongly on 145.825 MHz FM as 1200bps AFSK ASCII which can be read on any ham radio station rigged for terrestrial 2m packet. Only a simple dipole or almost any other kind of antenna is adequate for reception. So why not try retuning your terrestrial packet to 145.825 and wait until Dove triggers the squelch and starts to print up something like the following :- DOVE-1>TIME-1 : PHT: uptime is 005/19:21>55. Time is Fri Nov 12 13:35:11 1993 DOVE-1>TLM : 00:59 01:58 02:89 03:32 04:58 05:58 06:6D 07:50 08:6E 09:70 0A:A5 0B:F8 0C:E8 0D:DA 0E:30 0F:24 10:DE 11:9E 12:00 13:E3 14:AE 15:AB 16:72 17:70 18:72 19:73 1A:70 1B:25 1C:77 1D:71 1E:D8 1F:66 20:D4 DOVE-1>TLM : 21:C9 22:76 23:2C 24:24 25:26 26:70 27:01 28:4D 29:01 2A:03 2B:3F 2C:00 2D:8D 2E:63 2F:9E 30:CE 31:9B 32:03 33:00 34:A5 35:AA 36:AC 37:AC 38:A8 These are not ordinary numbers. They are hexadecimal. The 1st of each pair is the telemetry box address, the 2nd is its contents Eg 0A:A5 means that box hex 0A reports the actual volts on the 5v bus. To work out this actual volts , take contents hex A5 =165 , and feed this into the decode formula for this box , Volts = Contents times B (where B= .0305) =165 x .0305 = 5.0325 volts. In the same blocks of tlm ,boxes 26 hex to 2A hex change in 45 seconds from 26:70 27:01 28:4D 29:01 2A:03 to 26:01 27:44 28:66 29:01 2A:01 Taking box 26, it changes contents from 70 hex= 112 to 01 hex =1. Put this in its decode formula and we see that Solar array on the -X face of the satellite has changed current produced from +.22275 to -.0149 amps. If you check the other boxes you will see the +X array feeding box 27 has gone up, while the rest have stayed much the same. In fact these boxes tell you exactly how the satellite is spinning in relation to the Sun. You can check this by noticing that they all go to low contents values when the satellite goes into earth shadow. Pass times over Central UK for the next 2 weekends are utc :- 13 Nov 0939 1118 1258 1438 1618 1928 2103 2241 14 Nov 0911 1049 1228 1408 1549 1901 2035 2213 At other longitudes 20 Nov 0935 1114 1253 1434 1614 1924 2059 2238 these times local roughly 21 Nov 0907 1044 1224 1404 1544 1857 2031 2208 OK for station near 50N Note.. Pass times in other parts of UK may be a little different Northern stations may hear the near polar pass in the 1700 1800 gap Subtract roughly 28 minutes to get times of passes next day Timings always stay in 0900 to 0100 approx bracket 73 de GM4IHJ @ GB7SAN