[time-nuts] VLF Phase-tracking receivers.

[Kenneth G. Gordon]

On 9 Aug 2014 at 19:17, paul swed wrote:

> Ken 
> All of the phase tracking receivers no longer work due to the new bpsk wwvb
> modulation.

Hello, Paul. Yes. I knew that WWVB had switched to BPSK, but these 
receivers were specifically designed to tune to any of the VLF stations 
between 3 and 99.95 KHz. They used NAA, NPG, and GBR as examples.

> Certainly if you need accuracy any of the GPSDOs out there are
> better then the old wwvb receivers.

Well, I wasn't thinking so much of accuracy as simply watching the servos 
hunt. ;-)

> I have a 599 and will hope that the project I have been working on for far to
> long will allow it to track again.

Supposedly, it would track any of the VLF stations which transmitted 
phase-stable signals, even those which used FSK or its equivalent.

> As to the 1310s etc. Never heard of them.
> Something to search for on the internet. Regards Paul WB8TSL

Well, I have done just that.

I found two references to those: one was from a Canadian university project 
which was trying to use Phase-Tracking receivers to track the position of an 
ice-island. They were trying to use both an RMS Engineering 1312, and two 
Tracor 599s. Due to errors in their attempts to use the equipment with which 
they weren't familiar, they didn't have much luck.

The other reference was to an exchange on this very forum back in 2010...I 
think. Someone said they had been using a 1312 for 20 years.

Anyway, thanks for the help. Much appreciated.

Ken W7EKB