What is Your Take On Band-Pass Filters?

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KK4HG

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I am getting ready to add a second antenna which will be dedicated to commercial/private aircraft monitoring. I have used with success the AOR filter but am wondering if there is something better out there. Since I can't seem to find my AOR filter I will need to purchase a new one. Any suggestions in the $50.00 range?
 

KK4HG

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Well, I certainly appreciate the offer but I see two problems: Your filter has N connectors instead of BNC and it will not help me for freqs above the air band. I live close to a high rise building which is loaded with antennas on the roof, some of which are pagers in the 150mHz area, among others.
 

KK4HG

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75 Ohm cable is in use here so I typically use F to BNC adapters and I have a couple dozen of them. I just don't want to inject more adapters. My loss figures are probably staggering already!
 

iMONITOR

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You can also pick up Type N to F adapters for a few bucks. Or just pick up an FM notch filter for TV, that will already have F connectors on it.
 

poltergeisty

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75 Ohm cable is in use here so I typically use F to BNC adapters and I have a couple dozen of them. I just don't want to inject more adapters. My loss figures are probably staggering already!
Do they make filters that have F connectors on both ends? (Besides TV) You might be facing another coupler in your line...
 
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zz0468

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75 Ohm cable is in use here so I typically use F to BNC adapters and I have a couple dozen of them. I just don't want to inject more adapters. My loss figures are probably staggering already!
A couple of dozen in your actual receive path!? You're doing SOMETHING wrong. Be that as it may, the typical adapter has less than 0.1 db loss under 1000 MHz (not conjecture, I measured a bunch of them to settle the question once and for all).

If your losses are staggering, there are other problems besides too many adapters. Adding a couple to adapt from F to BNC is completely insignificant on air band frequencies.
 

KK4HG

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A couple of dozen in your actual receive path!? You're doing SOMETHING wrong. Be that as it may, the typical adapter has less than 0.1 db loss under 1000 MHz (not conjecture, I measured a bunch of them to settle the question once and for all).

If your losses are staggering, there are other problems besides too many adapters. Adding a couple to adapt from F to BNC is completely insignificant on air band frequencies.
No!! A couple of dcozen in my posession, not currently in use!
 

zz0468

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No!! A couple of dcozen in my posession, not currently in use!
Oh! Ok... Then keep in mind that, if you need to add a couple to a filter, or splitter (or whatever), the loss is completely insignificant for average quality adapters, and most of what you read about 1 db loss per connector or adapter is a myth. Just use 'em where you need 'em, avoid 'em where you can, and otherwise don't give it a second thought. They're only a loss issue when you go pretty high in frequency.
 

prcguy

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Press the Scanner Master button on the RR home page and look under filters. I purchased one that is an FM notch and 30MHz high pass for use in front of a preamp and it seems to work fine. I also swept this filter and it has very good skirts for a fairly simple and inexpensive filter. They also offer an air band, band pass only for $49 which fits your budget.
prcguy
 
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