I would like to add a few notes on receiving data from JAWSAT. Modems: JAWSAT has two GMSK modems. One is fixed at 9k6 (9600 bps) for transmit and receive. The other can be set to 9k6, 19k2, or 38k4. The receivers connected to the modems have their bandwidth set for 9k6 only. You can use a G3RUH modem but you may have a 3 db hit in performance. I have not found any "Ham" modems in the USA that use GMSK. If you know of any please let me know and so we can pass it along. I have purchased a GMSK modem kit from England. Check out http://www.gmskdata.co.uk/index.html for one source. We will try to use 9k6 and 38k4 only until someone comes up with a modem that can be easily switched between three receive data rates. If you think we should be using 19k2 let me know. I feel that if I have to changes filters on my radio I would go for 38k4 anyway so I can receive UO-36. Radios: Any radio/modem being used on the current 9k6 satellites (Ko-23,UO-32 etc) can be used to transmit to JAWSAT (9k6) and to receive at 9k6. For the 19k2 and 38k4 data rates we have been using a ICOM PCR-1000 receiver for testing on the ground. It will work for 38k4 but its wide FM 50 kHz filter limits it performance. I was able to receive UO-36 38k4 beacon packets using a PC-1000, a PacComm Spirit-2 TNC (Satellite Model), a Landwehr preamp and a KLM 40CX antenna. We have purchased cards for our FT-736 and IC-821 radios that will let them work at 38k4. See http://symek.com/sat/main.htm for information on the IFD, wideband FM highspeed data receiver/demodulator card. Antennas: The link calculation shows that the 1.6 watt 437.070 Mhz transmitter with a 1/4 wave antenna could send 38k4 data and be received on the larger 70 cm OSCAR antennas (14 db or more). The 2 watt 2403.2 Mhz transmitter with another vertical antenna and sending at 38k4 could be received with a 24 db antenna. We can adjust the RF power on the 437.175 Mhz transmitter from 0 to 8 watts. Running it at the highest power would allow 38k4 to be received by any antenna currently receiving the other 9k6 birds. Data format: We are still working on the final data formats to be used for sending down the PEST data. The data is saved in 8 megs of a RAM disk. So far we have been down loading the RAM disk a packet at a time. The data formats can be found at http://www.xmission.com/~kohlwey/jawsat.html. Updates will done to that web page first. Other modes: If the power budget allows it we may also have an analog FM "bent pipe" on while we are taking data. If the launch happens in the morning this is more likely to happen because we can use the 437.175 transmitter running at low power. Long term operation: In the long term I would expect the JAWSAT to be mostly in analog and not digital. Contacts: If you would like to help or need more information feel free to E-Mail me at n7sfi@amsat.org or Paul at kc7qfs@amsat.org