[RFI] TVI (digital TV)

[OZ1AXG Flam]

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 at dxmail.dk>
To: "RFI List" <rfi at 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 at contesting.com
> http://lists.contesting.com/mailman/listinfo/rfi
>


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