Newbie general antenna question

[bouges18]

I just purchased a Home Patrol 1 scanner and am in the process of picking a mobile antenna out for it. My question is, is there a specification to compare when trying to find out which has a better distance to pick up signals? Sorry for my lack of better wording, I couldn't think of a better way to ask the question. I understand there are different bands and frequencies that some are better designed to monitor. But if I have two tri-band antennas I'm looking at, is there a way to tell if one will pick up distant agencies better than the other? Does that have to do with gain or watts power? Again, newbie here. I apologize for my ignorance.

I live in Wright City, MO and will be monitoring agencies on a Interoperability - 700 MHz / P25 system. Thanks for your help.

 

[popnokick]

What are the two tri-band mobile antennas at which you are looking? The answer will allow others here to provide very specific info... perhaps even advice based on experience with the antennas.

 

[bouges18]

Reply

I am currently looking at the Larsen NMO150/450/800 and Maxrad BMAX-SCAN 1000 but I would be open to suggestions as well.

 

[popnokick]

Here you go... a full discussion thread devoted to these two antennas. Right here on RadioReference:
http://forums.radioreference.com/sc...rsen-150-450-800-maxrad-bmax-scan-1000-a.html

 

[bouges18]

Thanks but...

Thanks for the link. Yes I have read that forum discussion. However, it doesn't answer my question that I posted. Can someone explain if there is a specification to compare when trying to see which will pick up distant signals better? I may go with a different antenna separate from these.

 

[cpfinlay]

You will get the best reception getting an antenna for the specific frequency range you mentioned, rather than a multiband antenna. Gain antennas in the 700mhz range aren't even very large and quite inexpensive. If you live in a mountainous area, a simple 1/4 wave is your best bet. A multiband antenna is a compromise, and do not suit themselves to optimum range for any of the bands.

Gain is achieved by compression of lobes and that affects angles of radiation. If you live in the mountains, a gain antenna can be counter-productive, depending on terrain and antenna configuration. If you live in the flatlands and the system's sites are at a distance, something like a 5/8 over 5/8 collinear arrangement would be better. Give both a good ground plane (easy to do at 700mhz!).

 

[jaydigga]

I live in St Louis so I know what area you live in. I assume you want to monitor Ofallon PD and St Charles Co as well as Warren Co? I believe Warren Co is still using an older analog VHF system. Ofallon and St Charles Co are using a 700/800mhz P25 trunked system. If you care at all about listening to Warren Co I would suggest the Larsen as I have one and it is pretty decent on all bands IMO. If you only care about Ofallon/St Charles Co I would suggest an 800mhz specific antenna as the entire county switched over as of last Monday. Hope that helps