[TheList] antenna recommendation

Tue May 19 15:00:01 AEST 2020

I built my own one based on this:

https://lna4all.blogspot.com/2015/10/diy-fm-trap-or-88-108-mhz-band-stop.html

My SDR's were being swamped due to having a low band VHF antenna feeding 
an LNA and then onto the SDR's while the transmitters are at most 6KM 
away LoS. Probably not as much of a notch as you need though. It is just 
a Chebyshev filter after all so you can just build your own with more 
elements and enclose it in a diecast aluminium box with its own 
dedicated earth.

On 19/05/2020 2:04 p.m., Chris wrote:
> Yeah.. the Icom R30 scanner was just being overloaded when its was without the filter..
>
> once I put that in, I was able to listen to the ambo’s and fire again, but before that I was just being hammered with Broadcast interference.
>
> But yeah understood that was the case when it first went up there..
>
> I was really just asking if anyone had a better filter than the kingray - which is doing a good job, but I am sure there are better out there .
>
>> On 19/05/2020, at 11:09, Radio Engineering <radio.restorations at gmail.com> wrote:
>>
>> The trouble with being so close to the SkyTower is you will find that FM broadcast swamps everything. Filtering may help to a degree but you'll never block it out, there is so much RF coming off the stack. When the FM transmitters were first relocated to there they had to drop the output power of all of them as they were swamping things like car radios in the CBD, especially cheaper ones with not so good front ends.
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