[time-nuts] HP 3586A/B/C entirely referenced to 10MHz...

Poul-Henning Kamp phk at phk.freebsd.dk
Tue Mar 22 16:10:48 UTC 2011


In message <912589.3747.qm at smtp109.sbc.mail.gq1.yahoo.com>, "Burt I. Weiner" wr
ites:

>Within about 5 miles of my home I have two AM broadcast stations I 
>work with that are GPS referenced.  In spite of being so close to 
>these stations it's amazing to watch the phase rock slightly due to 
>propagation.

A lot of modern AM transmitters have a envelope tracking powersupply
for the output stage and this often introduce phase-shifts due
to voltage dependent capacitance.

It was quite noticeable when I measured it on the Danish MW 1062kHz
service some years ago.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.




More information about the Time-nuts_lists.febo.com mailing list