[time-nuts] Rapco 1804M manual and Control Mode Access ?

[gandalfg8 at aol.com]

Hi Chris,



I posted a manual to mediafire some time back, have just checked and the link is still working......



http://www.mediafire.com/file/5evbveha6pccc1l/Rapco_1804M_1882M.pdf/file



This is a combined manual for the 1804M MK2 GPSDO and 1882M2 MK2 distribution amp, both black

fronted and quite common as surplus at one time.



The Trimble GPS module is an SVee6, end of life notice for that was May 1999.

At one time I thought Rapco also used the SVee8 in some of these but suspect now that both modules might have been the SVee6 but one

with just one 9 pin connector and the other with two.



Link also for the SVee6 manual....



http://www.mediafire.com/file/5anjbqqksv8pm4q/SveeSix+revC+Optimised.pdf/file



I've got notes from 2014 regarding date problems with some 1804P2 10MHz units, which seemed at first to be a GPS rollover issue but

was resolved by swapping around the Rapco firmware for those, but wouldn't be at all surprised if there were now rollover problems with all

of these, although this shouldn't retrict use as a GPSDO.



It sounds like you're talking to it ok but have found this note in my files just in case.... 



The Rapco 1804xx to PC connection requires a null modem cable, a laplink type cable is fine,

and uses a baud rate of 4800 with 8 data bits, 1 stop bit, and no parity.

It works ok with either hardware flow control or no flow control.



I'm pretty sure I used Hyperterminal.



Nigel GM8PZR





---------------------------



Hi,

Looking for the user manual for the above gpsdo. At power
up, keeps repeating gps status and time, whereas there
is an internal control mode for setup. Works fine and
locks to gps, but the year is stuck at 2001, suggesting
a date rollover bug.

Internal GPS engine a a (Trimble ?) TNL22880 and a manual
for that would be a help. If the bug is not fixable,
perhaps a later trimble gps engine could be substituted,
as the protocol may be common.

This is a 5MHz unit with pps, and useful around the
lab as a reference for some older test gear...

Regards & Thanks,

Chris