Re: [time-nuts] GPS shielding by power lines?

and frequency measurement time-nuts@febo.com Sent: Monday, August 11, 2008 5:12 AM Subject: Re: [time-nuts] GPS shielding by power lines? You didn't say if you tried the antenna under the power lines but outside the cabin. What is translucent to light may not be to microwaves. David N1HAC

Re: [time-nuts] GPS shielding by power lines?

Message - From: David Ackrill [EMAIL PROTECTED] To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sunday, August 10, 2008 8:30 AM Subject: Re: [time-nuts] GPS shielding by power lines? Alan Melia wrote: Hi all, in the process of setting up a GPS time standard

Re: [time-nuts] GPS shielding by power lines?

.(?) Thanks Alan G3NYK - Original Message - From: Thomas A. Frank [EMAIL PROTECTED] To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sunday, August 10, 2008 6:38 AM Subject: Re: [time-nuts] GPS shielding by power lines? Alan; I have no idea

Re: [time-nuts] GPS shielding by power lines?

On Sun, 10 Aug 2008 10:27:31 +0100, Alan Melia wrote: I note there lines have three phase feeds but no neutral wire so they must use ground as the return path to any unbalance currents.(?) As long as the system is kept balanced a 3 phase energy transport system does not need a 4th wire as

Re: [time-nuts] GPS shielding by power lines?

Alan Melia wrote: Hi Tom Brilliant I hadnt thought of the fields actually affecting the operation of the electronics! that is certainly something that might be interesting to check. I note there lines have three phase feeds but no neutral wire so they must use ground as the return path to any

Re: [time-nuts] GPS shielding by power lines?

Arnold Tibus wrote: As long as the system is kept balanced a 3 phase energy transport system does not need a 4th wire as the sum of all the currents in the 3 wires (phase shift 120deg between the wires) is zero! regards Arnold, DK2WT That is true Arnold, but in the UK (and in some other

Re: [time-nuts] GPS shielding by power lines?

Around all high voltage lines the air is somewhat ionized and this may result in sufficient free electrons to seriously mess up the GPS signal, although I wouldn't expect much trouble from a 11kV line. The fact that the navigation message is 50Hz in the GPS signal and the power-grid in the UK is

Re: [time-nuts] GPS shielding by power lines?

Poul-Henning Kamp wrote: The fact that the navigation message is 50Hz in the GPS signal and the power-grid in the UK is close to 50Hz is not a good thing in any case. By UK law, it must be within +/- 1% of 50Hz. :-) Dave (G0DJA) ___ time-nuts

Re: [time-nuts] GPS shielding by power lines?

...so will have to be careful. Thanks Alan G3NYK - Original Message - From: Didier Juges [EMAIL PROTECTED] To: 'Discussion of precise time and frequency measurement' time-nuts@febo.com Sent: Sunday, August 10, 2008 12:52 PM Subject: Re: [time-nuts] GPS shielding by power lines? Alan, I

Re: [time-nuts] GPS shielding by power lines?

In message [EMAIL PROTECTED], David Ackrill writes: Poul-Henning Kamp wrote: The fact that the navigation message is 50Hz in the GPS signal and the power-grid in the UK is close to 50Hz is not a good thing in any case. By UK law, it must be within +/- 1% of 50Hz. :-) Yeah, but the fact that

Re: [time-nuts] GPS shielding by power lines?

- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Alan Melia Sent: Sunday, August 10, 2008 8:17 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] GPS shielding by power lines? Hi Didier, thanks for that idea, yes they were all pucks all

Re: [time-nuts] GPS shielding by power lines?

[EMAIL PROTECTED] To: 'Discussion of precise time and frequency measurement' time-nuts@febo.com Sent: Sunday, August 10, 2008 12:52 PM Subject: Re: [time-nuts] GPS shielding by power lines? Alan, I don't believe you have said what type of antenna you are using. If you are using a true

Re: [time-nuts] GPS shielding by power lines?

Around here they place cell antennas on a monopole down the center of power transmission line towers. The GPS antennas are invariably directly below the 100-200kv lines. The GPS signal must be reliable enough or the cell sites wouldn't be there. Scott Alan Melia wrote: Hi all, in

Re: [time-nuts] GPS shielding by power lines?

On Sun, 10 Aug 2008 13:05:47 +0100, David Ackrill wrote: Arnold Tibus wrote: As long as the system is kept balanced a 3 phase energy transport system does not need a 4th wire as the sum of all the currents in the 3 wires (phase shift 120deg between the wires) is zero! regards Arnold,

Re: [time-nuts] GPS shielding by power lines?

You didn't say if you tried the antenna under the power lines but outside the cabin. What is translucent to light may not be to microwaves. David N1HAC At 05:15 PM 8/9/2008, you wrote: Hi all, in the process of setting up a GPS time standard for a Radio Astronomy facility (amateur) we

[time-nuts] GPS shielding by power lines?

Hi all, in the process of setting up a GPS time standard for a Radio Astronomy facility (amateur) we installed a GPS receiver in a small cabin with a translucent roof, thinking that would not impede the GPS signal. After a lot of head scratching as to why we were not getting the performane we got

Re: [time-nuts] GPS shielding by power lines?

Alan Melia wrote: Hi all, in the process of setting up a GPS time standard for a Radio Astronomy facility (amateur) we installed a GPS receiver in a small cabin with a translucent roof, thinking that would not impede the GPS signal. After a lot of head scratching as to why we were not getting

Re: [time-nuts] GPS shielding by power lines?

The thought was that there as interference arcing or corona noise from the line insulators, and a receiver (AM) was deployed to listen for what was expected to be a substantial wide band noise signalwe didnt hear one! We are now confused about what the effect is. The signal could