[time-nuts] Active LORAN antenna

Poul-Henning Kamp phk at phk.freebsd.dk
Fri Aug 26 19:27:23 UTC 2011


In message <4E57CBEE.3000509 at pacific.net>, Brooke Clarke writes:

>You might consider the AMRAD active antenna that they designed for the 
>136 kHz ham band.

If you want to build an active monopole, Chris Trasks "secret" design
is far better and far more manageable than the AMRAD:

	http://www.home.earthlink.net/~christrask/Paper007.html

I built this one with BFQ19+BQ149+J174+J310 all in SMD parts.

(J270 is a better choice than J174 which tends to forward bias)

With my primitive measurement methods, it was flat to 100 MHz
and tapered off just short of 800MHz.

In the other end it reliably pulls out the Russian ELF (OMEGA like)
navigation system down around 10kHz.

Chris mentioned that a kit might be underway, but I havn't seen
any sign of it anywhere...

-- 
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.



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