Any thing better than Larsen NMO 150/450/800 Antenna?

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6520tkp

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I have been using the Larsen NMO 150/450/800 Antenna with great results on my vehicle for several years.
Recently every one has switched to "digital" and my scanning reception mobile is almost nothing.

I had to relocate and elevate my base antenna and I have great reception at home, I need to work on my reception while mobile.

I know there are other factors invovled such as scanner decoding, site location ( which might be the problem) etc.. .

My question is, is there anything available with more gain.

My scanner is a BCD 396T which I think could do a better job at decoding.


Majority of my scanning is mobile, any suggestions ?

Thank You.
 

n5ims

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Jul 25, 2004
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3,695
I have been using the Larsen NMO 150/450/800 Antenna with great results on my vehicle for several years.
Recently every one has switched to "digital" and my scanning reception mobile is almost nothing.

I had to relocate and elevate my base antenna and I have great reception at home, I need to work on my reception while mobile.

I know there are other factors invovled such as scanner decoding, site location ( which might be the problem) etc.. .

My question is, is there anything available with more gain.

My scanner is a BCD 396T which I think could do a better job at decoding.


Majority of my scanning is mobile, any suggestions ?

Thank You.
The #1 factor for "Is this antenna good for me?" is what frequency or frequencies do you monitor and does the antenna cover those in its primary design. If you listen to mostly the VHF-Low band (think 30 - 50 MHz here) and your antenna is the absolute best one available for the 800 MHz band, you'll have very poor results. Also the reverse it true, if you listen mostly to the 800 MHz band (think 700 - 950 MHz here) and your antenna is the greatest one ever built for the VHF-Low band, you'll also have very poor results.

The antenna cares about 1 think, frequency. It doesn't really care what kind of radio it's connected to. It doesn't care if the signal is analog or if its digital. If the frequency is a good match, it'll work great. If not, it'll work poorly.

Now, let me step off my soapbox and attempt to answer your question. First off, if you can provide more details on what you monitor (frequencies would be good, links to them from the RR database even better) a more specific answer to what will work best for YOU can be provided, but here are some generalities that should help you regardless.

The Larsen tri-band antenna covers the VHF-Hi, UHF, and 800 MHz bands quite well. It basically has no gain on the VHF-Hi band, a bit of gain on the UHF band, and somewhat more gain on the 800 MHz band (more gain is better, incase you don't know). Note that I'm talking real gain here (dBd), not gain that's only there in theory (dBi) so this is something that will actually help your signal strength, not something that just makes the antenna look good from a marketing standpoint. I have several and they do the job well on the bands it's designed to cover, which are those that most systems actually use. If you really need coverage on the VHF-Low band, it may not be the antenna for you but otherwise it'll do just fine.

There is one think that could be causing you issues with your reception (those links I asked for earlier would help confirm this), the simulcast distortion issue. If one or more of your systems use a simulcast system (where multiple towers broadcast the same signals on the same frequency to enhance coverage for their handheld radios) it's quite likely that you may be experiencing this issue. What happens here is the signal degrades when your scanner picks up more than one of the towers with sufficient signal strength so they combine and distort the signal. While it appears that you don't have enough signal, you actually have too much signal (yes, this can be a very bad thing!). A better antenna could actually make the situation worse, not better. I'm very close to one of the Plano towers and what works best for that system is something you probably won't believe, but it's true - no antenna at all beats everything else I've tried. On another system that works great most of the time but has trouble in spots while mobile using my handheld scanner, I'm able to pick them up just fine by grabbing the bottom of the antenna to have my hand shield it from the signals so they're reduced enough so that only a single tower is strong enough to be heard and the distortion is eliminated so I hear things just fine. Once I'm out of the offending area, I let go and again hear just fine.
 
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6520tkp

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Nov 14, 2007
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Thank You for your advise, I failed to say I am listening to the Fort Wort Regional Radio System Layer 2, North Richland Hills, Richland Hills, Watauga and Haltom City.

According to the site map I am between the Keller and Bedford Tx. sites.

Very well put, thank You.

Maybe I should down grade for a new antenna (Ha Ha).

It just annoying I can't receive like I did before.

I guess I am going to have to live with being in between 2 sites.

Thanks again for the help.
 

6520tkp

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Nov 14, 2007
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144
Rubber Duck

Maybe I should use my original rubber duckie antenna while mobiling.

Worth a try.

Thanks again.
 

n5ims

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Jul 25, 2004
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Maybe I should use my original rubber duckie antenna while mobiling.

Worth a try.

Thanks again.
That's what I use (actually the RS 800 MHz antenna) which gives me the ability to use my hand as a temporary attenuator as I indicated in my above post.
 

teufler

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Dec 19, 2002
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ST PETERS, MISSOURI
what I went to maybe 10 years ago was a Uniden Wide Band Pre Amp. Basically 20mhz to 1 gig. I'm not sure Uniden makes them anymore but there are others that are ouit there. On marginal signals, 780xlt shows 2 bars to 5 bars or full scale. On stronger signals, does not do much but for bring in stations while you are on the fringe, it does do the job. Simpler design, the dc pwr cable that normally powers the radio, you plug that into the pre amp then you have a cable that is attached to the preamp that now plugs into the scanner. You have a short patch cable that connects the pre amp to the scanner and you are done. I use it also with the 396xl scanner thru the use of some adapters. The signal loss with adapters is small or non-existant. It does NOT work if you are running the 396xl remotely or just carrying it around.
 

Mastiff2013

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Apr 8, 2013
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I have been using the Larsen NMO 150/450/800 Antenna with great results on my vehicle for several years.
Recently every one has switched to "digital" and my scanning reception mobile is almost nothing.

I had to relocate and elevate my base antenna and I have great reception at home, I need to work on my reception while mobile.

I know there are other factors invovled such as scanner decoding, site location ( which might be the problem) etc.. .

My question is, is there anything available with more gain.

My scanner is a BCD 396T which I think could do a better job at decoding.


Majority of my scanning is mobile, any suggestions ?

Thank You.
What did you decide on?
 
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