to: John,KE5FX Hi John I read your question on the THUNDERBOLT look-alike sold by 'accelium'. Since I have bought this unit (for 500$!!!), I can answer some of it:
The hp58533a has a similar form factor as the Thunderbolt but it's an entirely different design. I made the following notes when trying it out: - simplified version of hp58540a where data sheet is available. (missing power supply board and cheaper TCXO by TOYOCOM). Separate 5V and 15VDC (for TCXO) have to be supplied instead of 18...32 VDC is the '540a. - while the data sheet boasts SCPI on the rs-232 interface, this unit pours out NMEA messages every second (no SCPI prompt could be effected): $GPGGA,135308,4656.5706,N,00723.4843,E,0,04,00.50,000562.6,M,0049.4,M,, $GPZDA,135308,10,01,2007,-04,00 $GPGSV,3,1,09,03,79,152,54,08,06,309,00,11,14,264,29,14,10,129,33 $GPGSV,3,2,09,16,18,183,40,18,33,051,43,19,66,304,31,21,07,071,29 $GPGSV,3,3,09,22,60,091,55 $GPVTG,,T,,M,,N,,K $PFEC,GPtps,070110135308,3,1,2,060101000000,00,14,070110023110,1409,309202 ...the last line made me suspicious because it's a proprietary code used by FURUNO! - inspection of the board brought the proof, because one IC is from FURUNO. - data are displayed in any NMEA compatible GPS program like TAC32 or Trimble's GPDDS:EXE for DOS. - missing of course any information on timing, since PFEC is not decoded. - 10 MHz and 1PPS outputs operate always, so no integrity check seems to be performed. - quality of 10 MHz was fair: r.m.s 3.6e-11 with tau 60s - 1PPS was found within expectations but no long-term observation has been made so far - processor seems to work real slow; TOF was one hour or so woth Conclusion: unit is useful but in no way as interesting for research as TRIMBLE's Thunderbolt or its derivative, LUCENt'S GPSTM. QUESTION: does anybody know mire about the FURUNO code mentioned above????? Regards Paul TM-Brokers of Switzerland _______________________________________________ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts