Return to KLUBNL.PL main page

rsgb_lf_group
[Top] [All Lists]

RE: LF: Timing GPS and Spam

To: [email protected]
Subject: RE: LF: Timing GPS and Spam
From: "Talbot Andrew" <[email protected]>
Date: Mon, 16 Feb 2004 09:20:58 -0000
Reply-to: [email protected]
Sender: <[email protected]>
1)
Since transferring this reflector to my works computer and cancelling the
old home EMail address most spam has stopped.  However, I now get the
occasional one to work which gets through the firewall.  Obviously the LF
reflector has something to do with this, but at least one per fortnight is
better than 40 per day !

2)
I have done some further tests on the Jupiter T GPS module with its 10kHz
output.   Phase locking this to a 5MHz reference suggests a really good (for
LF to HF use anyway) GPS Discpiplined oscillator is trivially simple - it
doesn't need a high spec ovenned oscillator and provided it is used with a
bit of common sense, doesn't even need to use a controller to read the data
coming out.  Just a small voltage controlled TCXO, two 74HC390 chips to
divide this down to 10kHz, an EX-OR gate as a phase detector and a handful
or Rs and C.  Once the GPS Rx has locked up, the PLL takes a further couple
of minutes to lock and its all going.  A good quality source, with a short
term stability of fractions of a Hz over seconds and perfect in the long
term.

I will write this up soon - the Jupiter-T GPS module is not cheap compared
with some of those around - but the ease with which it can be used as a good
frequency standard...

Andy  G4JNT



"This e-mail is intended for the recipient only.  If you are not the
intended recipient you must not use, disclose, distribute, copy, print,
or rely upon this e-mail. If an addressing or transmission error has
misdirected this e-mail, please notify the author by replying to this e-mail."

"Recipients should note that all e-mail traffic on MOD systems is
subject to monitoring and auditing."


<Prev in Thread] Current Thread [Next in Thread>
  • RE: LF: Timing GPS and Spam, Talbot Andrew <=