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Robert Miles Robert Miles is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 13
Default Active antenna for Navtex reception

Hi,

I recently purchased an ICS NAV-5 Navtex that came without an antenna.

Reading user guide and docs on the web I can purchase and fit a NAV 4
passive antenna or an active VTRONICS ..
Being inquisitive I wondered what is in these?

Can't find a CCT of them but found some very interesting articles on use of
short whips ( as used in the active antenna) at LF, in particular the high
impedance antenna being couple to the gate of an FET.. a few comments on
making sure the whip is insulated, and likely life of the FET if any static
or lightning about. Makes me wonder if a passive ant would be more reliable
than an active ant?

Does anyone have any experience of active antenna use and reliability?

PS NAVTEX reception around the Clyde/West Scotland is reported as poor so an
active ant might be attractive

Regards

Bob


GM4CAQ

Simply Blue Too
Clyde