Hi
Followup:
I have examined specs of the equipment used. The digital decoder box
receiver includes 6 meter and 2 meter ham band. Combined with a very weak TV
signal, this make the TVI pretty bad. This is also true for at least one of
the active antenna's used in the installation.
I build a TVI filter from this instructions:
http://www.uksmg.org/content/filter.htm
Does anyone have any idea where the cutoff frequence (i.e. -3dB) is for this
filter ?
As instructed i put the filter in a plastic box:
http://home.cbkn.dk/dx/images/oz1axg.UHF.Filter.JPG
Wouldent it be better to use a metalbox ? or will stray capacity spoil the
effect of the filter ?
Is there any way to fix the problem with the active antenna, any idea's ?
"digital antenna" lookes like this:
http://parabolspecialist.dk/shop/digiality-maximum-da-1022p.html
I lent a digial box of a friend and will try at test setup with the filter.
Also gota braid breaker, but that wil only solve the below 30 MHz TVI.
--
OZ1AXG Flam
----- Original Message -----
From: "OZ1AXG Flam" <oz1axg.nospam@dxmail.dk>
To: "RFI List" <rfi@contesting.com>
Sent: Monday, December 08, 2008 10:57 PM
Subject: [RFI] TVI (digital TV)
> Hi
>
> Any idea where i can pick up a 480 MHz HIGH pass filter for TV (or build
> one)... i have tried local stores and danish internet shops wthout any
> luck.
>
> Transmitting on anything from 1.8 to 434 MHz blacks out the nighbours TV.
> We
> have located the problem the the Digtial ReceiverBox (proberly the build
> in
> pre-amplifier is without any form of antenna input filtering).
>
> In a distance of 5 meters from the antenna, using 100 mW with my VX-2 on
> 145.550 MHz, i can block the reception. The signal goes to zero on the the
> receiver box.
>
> Setup:
> [TV
> antenna]----------------------------->[ZapperBox(digitalTVdecoder)]------------>[TV]
>
> http://www.digi-tv.dk/
>
> --
> OZ1AXG Flam
>
>
> _______________________________________________
> RFI mailing list
> RFI@contesting.com
> http://lists.contesting.com/mailman/listinfo/rfi
>
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