[time-nuts] Trimble/Nortel 45000 GPS Locked Reference Oscillatorboard
quartz55 quartz55 at hughes.net Tue Dec 24 10:06:49 EST 2013 I'd like to see some of your LH traces if you don't mind, especially the osc trace. I don't seem to be able to get my osc trace less than ~400 ppt/div. ++ Here is a 17 hour LH plot of my NTPB15AA 05 which is about the same device, although perhaps a little older. I've found this particular unit very stable. I do have a NTBW50AA which isn't quite as stable but still pretty good. http://i906.photobucket.com/albums/ac262/rjb1998/tbolt12112013_zps21348f7b.gif -Arthur ___ 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.
Re: [time-nuts] Trimble/Nortel 45000 GPS Locked Reference Oscillatorboard
That Nortel board you have there looks exactly like the board I got in my Nortel NTBW50AA GPSTM. You can find the book on-line, look for Dual Voltage Global Positioning System Timing Module (GPSTM) OEM General Specification. Yes the power supply is speced from 24 to 48VDC plus or minus. They don't specify AC, but since the bridge is there it will work. 2.08A warm up and .6A@36VDC steady state. I'd like to see some of your LH traces if you don't mind, especially the osc trace. I don't seem to be able to get my osc trace less than ~400 ppt/div. You can see pics of my unit and traces from LH here http://s251.photobucket.com/user/DogTi/library/time?sort=3page=1 Dave ___ 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.
Re: [time-nuts] Trimble/Nortel 45000 GPS Locked Reference Oscillatorboard
Dave, my opinion is that this big tree around your GPS antenna causing a lot of trouble as especially when the tree are wet... Rgds Ernie. -Original Message- From: quartz55 quart...@hughes.net To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Tue, Dec 24, 2013 4:10 pm Subject: Re: [time-nuts] Trimble/Nortel 45000 GPS Locked Reference Oscillatorboard That Nortel board you have there looks exactly like the board I got in my Nortel TBW50AA GPSTM. You can find the book on-line, look for Dual Voltage Global ositioning System Timing Module (GPSTM) OEM General Specification. Yes the ower supply is speced from 24 to 48VDC plus or minus. They don't specify AC, ut since the bridge is there it will work. 2.08A warm up and .6A@36VDC steady tate. I'd like to see some of your LH traces if you don't mind, especially the osc race. I don't seem to be able to get my osc trace less than ~400 ppt/div. You an see pics of my unit and traces from LH here http://s251.photobucket.com/user/DogTi/library/time?sort=3page=1 Dave __ ime-nuts mailing list -- time-nuts@febo.com o unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts nd 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.
Re: [time-nuts] Trimble/Nortel 45000 GPS Locked Reference Oscillatorboard
On Tue, Dec 24, 2013 at 9:06 AM, quartz55 quart...@hughes.net wrote: That Nortel board you have there looks exactly like the board I got in my Nortel NTBW50AA GPSTM. You can find the book on-line, look for Dual Voltage Global Positioning System Timing Module (GPSTM) OEM General Specification. Yes the power supply is speced from 24 to 48VDC plus or minus. They don't specify AC, but since the bridge is there it will work. 2.08A warm up and .6A@36VDC steady state. Just because it has a bridge to allow connection of floating +24VDC or -48VDC doesn't mean it is a good idea to apply AC. The input filter caps may not be designed to handle the ensuing ripple current. I would tread lightly in this area. -- Brian Lloyd, WB6RQN/J79BPL 706 Flightline Drive Spring Branch, TX 78070 br...@lloyd.com +1.916.877.5067 ___ 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.
Re: [time-nuts] Trimble/Nortel 45000 GPS Locked Reference Oscillatorboard
Brian wrote: Just because it has a bridge to allow connection of floating +24VDC or -48VDC doesn't mean it is a good idea to apply AC. The input filter caps may not be designed to handle the ensuing ripple current. I would tread lightly in this area. Not only that, the value of the filter cap in the unit is almost certainly not large enough to reduce the ripple sufficiently, so the internally regulated supplies will, in turn, have more ripple than they should. In this case, the bridge is not there to be an AC rectifier, it's just there to allow DC of either polarity to work. Use a DC supply. Best regards, Charles ___ 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.
Re: [time-nuts] Trimble/Nortel 45000 GPS Locked Reference Oscillatorboard
Hi Dave, Thanks for your post. I'd like to see some of your LH traces if you don't mind... Do you mean with the Lady Heather software? I'll leave it running a while and collect some data. Yes, I did hesitate running it on AC, but it draws little current and does seem to be happy enough. I do have a switch mode supply to put in the box eventually. regards Zim . VK3GJZ ___ 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.
