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.