FM Filter?

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737mech

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Hey
I read here: Testing a FM Broadcast Bandstop Filter - rtl-sdr.com that an FM Filter are good.
So that what the Guy use cost ~40€ shipping so i looking for some different and i found this:
SPAUN Edition 17 but does i give me an benefit for ACARS decoding?
Thanks

Sir your benefit to the FM trap depends on the environment you are in, like a busy city with many FM radio stations and lots of cell towers. I'd suggest you examine the noise floor via SDR and then decide if you need a FM Trap. There are less expensive alternates you could try first. No doubt they work great if you are like me in a very active RF city. The VHF airband opens up better with a FM trap installed. That would improve acars receiving on your scanner. Radioshack sells a cheap FM trap to try at first. That's the joy of this hobby try things and try to improve.
 

Your_account

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Radioshack sells a cheap FM trap to try at first.
I am from Europe (Austria) and i cant buy it there.
Product cost fo example 5$ and shipping 50$ + Custom Tax,...
So that product is the only i found who is selling in Europe and "cheap".
The problem is i dont know anything about Radio. Is there any Youtube Video who show me the noise Level before and after that filter?
I buy an cheap CableTV Amplifier and a 8x Hub to listen many Stations. Where does i have place to filter?
A -> F -> H ?
 

zz0468

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The problem is i dont know anything about Radio.

That makes it difficult. You somehow need to determine whether or not you even need an FM filter. That typically requires some test instrumentation, and the skill sets to use it.

Are you trying to solve a specific problem, or are you just grasping at straws hoping to improve reception?

Is there any Youtube Video who show me the noise Level before and after that filter?

No. The flaw with that approach is that every case is different, and interference on some YouTube video is highly unlikely to be identical to interference at your location.

I buy an cheap CableTV Amplifier and a 8x Hub to listen many Stations. Where does i have place to filter?
A -> F -> H ?

The filter would be placed between the antenna and the first active device, whether that's the receiver, a preamp, or your multicoupler/splitter device.

What's happening that makes you think you need a filter?
 

vagrant

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Here are two filter options from a company in Czechoslovakia that is located north of you about 150 kilometers.

Air band filter: Radiokomunikaèní a mìøicí technika, antény, kabely, GPS navigace - DDAmtek

- or -

High pass filter & FM notch filter: Radiokomunikaèní a mìøicí technika, antény, kabely, GPS navigace - DDAmtek

I personally use the HPN-30118 High pass/notch filter. I have terrible AM and FM broadcast band issues at my home and that filter works very well for my needs.

* For those that are wondering I also have the Radio Shack FM Trap filter and based on signal strength and my ear they work the same. As the RS filter is only $5 versus $50 for the HPN-30118 from Scannermaster, it's up to you. I also have some AM issues and yes I have a PAR AM filter too. Still, it is a convenient connector (HPN-30118) that eliminates having to pigtail the RS FM filter and the PAR AM filter with a plethora of connectors between. Your mileage may vary.
 

Your_account

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a company in Czechoslovakia
thats the reason why many people think Americans are stupid...
The Československá republika never exist since 1992....
thx i will oder DDAMTEK HPN-30118 but how can i do i with the differnt plugs?
 
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