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Author Topic: atu for 2 m  (Read 741 times)

Offline G6URM

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  • Country: england
atu for 2 m
« on: February 13, 2017, 12:02:13 UTC »
  here a simple atu for 2 meters - 100 pf Vc - coils 5 turns on a 45 mm former ( drill bit )  nothing complex - ok up to about 25 w depending on plate spacing  - will work with long wires too - note the TOP of box mounted o/p so239 or n- type socket  ( to which you could screw a 1/4 wave or whatever for a simple expediant antenna )  - the  brass bolt is the earth point and you should use a counterpoise rod or wire at least 1/4 wl long here if using it as a stand alone antenna base

Offline iw1au

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    • RadioManual.eu
Re: atu for 2 m
« Reply #1 on: February 17, 2017, 22:27:59 UTC »
Hi!
Could you attach a diagram, also hand made, to be more sure? Do you have some pics also?
Thanks.
--
73 de IW1AU, Gian Maria
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http://iw1au.altervista.org/
http://www.radiomanual.eu/

Offline vu2nan

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  • Country: in
  • Nandu - VU2NAN since 1977.
    • Amateur Radio VU2NAN - Nandu
Re: atu for 2 m
« Reply #2 on: February 23, 2017, 04:31:38 UTC »
Hi OM Brett,

Please try uploading the images again. However I am able to visualise it since I have seen commercial 2m and 70cm ATUs. I am sure the former diameter is 4.5mm (decimal point missing!).

Having the output connector on top along with a point to connect a radial is a good idea.

Have fun!

73,

Nandu.