I have several of these, all work well, all take some time to settle down after the control LED comes up. I can't remember now if any of mine have shown fine either but have compared all with a trio of Thundebolts and all work well as I say. There's a manual for the Rb version available from at least two of the UK Ebay suppliers so worth asking if you bought from there. All you need is in the manual and the Rb command set is very similar to the OCXO version but I can let you have a pdf copy of the proper OCXO version manual next week if you don't get one before then. I'm away from home right now and internet is very hit and miss here but will be back Wednesday. regards Nigel GM8PZR
Hi Just joined the list - recently acquired a Rapco 1804m, mainly to use as a frequency standard, especially to have something to check the FE-5680A that I have. The unit itself seems to work OK - connected to a cheapie puck style GPS antenna I got a 2D fix, occasionally 3D which corresponded pretty well with my actual location and "Coarse" oscillator lock, but never "Fine". It's the version with an OXCO rather than local Rubidium oscillator. I've read David Taylor's notes and had a hunt through the list archives - I suspect I need a slightly better antenna, or a better position for the one I already have. It had a decent enough view southwards/southwest but somewhat obstructed to the north and north-east and comparing the visible satellites on my 'phone it was certainly the northerly/north-eastern ones that had low or no signal strength. However I could really do with a copy of the manual, at least to understand the difference between "Coarse" and "Fine" locks on the oscillator - does anyone have an electronic copy that they would be willing to let me have? Or a physical copy - I'm happy to pay a reasonable sum. Also is the serial protocol for these documented anywhere? -----Original Message----- From: Paul Flinders <p...@flinders.org> To: time-nuts <time-nuts@febo.com> Sent: Sun, 3 Jun 2012 11:16 Subject: [time-nuts] Rapco 1804m Hi Just joined the list - recently acquired a Rapco 1804m, mainly to use as a frequency standard, especially to have something to check the FE-5680A that I have. The unit itself seems to work OK - connected to a cheapie puck style GPS antenna I got a 2D fix, occasionally 3D which corresponded pretty well with my actual location and "Coarse" oscillator lock, but never "Fine". It's the version with an OXCO rather than local Rubidium oscillator. I've read David Taylor's notes and had a hunt through the list archives - I suspect I need a slightly better antenna, or a better position for the one I already have. It had a decent enough view southwards/southwest but somewhat obstructed to the north and north-east and comparing the visible satellites on my 'phone it was certainly the northerly/north-eastern ones that had low or no signal strength. However I could really do with a copy of the manual, at least to understand the difference between "Coarse" and "Fine" locks on the oscillator - does anyone have an electronic copy that they would be willing to let me have? Or a physical copy - I'm happy to pay a reasonable sum. Also is the serial protocol for these documented anywhere? _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
