Railfan Technology > Mobile (vehicle) amateur radio for RR use?

I have an old Yaesu FT2400M that has fritz'd out on me a couple times; I see lots of options on the 2M Mobile market for computer-programmable radios.  Any hams have a preference one way or the other?  I would consider a 2M/70CM radio to gain the ability to receive the EOT/HOT frequencies as well.
Thanks in advance,
-Alex

This is a tough one.  I have tested numerous dual-band mobile radios over the last year.  I have yet to find one that I can recommend.  The Japanese dual-band amateur radios all have 5 kHz tuning steps which will not tune the "splinter" analog VHF frequencies that are authorized for railroad use.  I've tested several of the Chinese dual-band mobile amateur radios.  They have 2.5 kHz tuning steps that will tune the splinter channels, but suffer from numerous other deficiencies--archaic or difficult computer programming software, poor selectivity and sensitivity, glacially slow scan speeds, minuscule displays, etc.  In my main railfan vehicle, I have a commercial Icom IC-F5061D VHF radio, and an old Kenwood TM-G707A dual-band radio that I kept in the vehicle for amateur radio use--I use it to monitor the UHF train telemetry signals.  I don't use the VHF side of it for railfanning.  Of course, that means two radios in the vehicle and two antennas.  That combination of radios works well.  I just acquired a newer secondary vehicle and I currently have another IC-F5061D VHF radio installed in it, but no UHF mobile  radio.  For now, I just throw my dual-band portable radio up on the dash, tuned to the UHF train telemetry channels--not an optimum setup, but what I will use until I find a decent dual-band radio that I can recommend.  Also, a Japanese dual-band amateur mobile radio can often cost as much as a very good single-band commercial mobile radio.

If you are looking for a good single band VHF amateur radio, the best I ever have seen is the Kenwood TM-281A.  Sadly, it was discontinued, and prices for them on the used market have skyrocketed to as much as double or triple their price new.  It's too bad, it was an outstanding performer--I believe it was built on a commercial Kenwood radio chassis, with just slight hardware and firmware mods to make it an amateur radio.

EDIT:  I just did find some new TM-281A radios advertised on Ebay for $172.00.  At that price, the 281A would be a smokin' deal.



Edited 2 time(s). Last edit at 09/16/22 18:40 by WW.

I have used the Icom 2720-2730 series of duo band radios for many years with
good results.

The feature I most like is the "VV-UU" capability which allows you to choose 2
different RR channels and have, for example, the road channel come out on a
speaker mounted on the driver's side of the car and the dispatcher come out
of. a speaker mounted on the passenger side.  This setup could also be used to
monitor 2 different RRs.

I've found them to be reliable and good performers.  If you are familiar with the
Icom "system" they are easy to program, if not RT Systems offere a kit with a
disc and suitable cable that is a snap to use.

73

Tim Colbert  K3HX

Have we identified any railroads using splinter channels yet?

Are they of concern to the OP?

TCnR Wrote:
-------------------------------------------------------
> Have we identified any railroads using splinter
> channels yet?
>
> Are they of concern to the OP?

My guess is that they, if used, will most commonly be used in large metro areas where there is a lot of "congestion" in the number of channels in use.  I try to spend as little time as possible in such metro areas, so I haven't personally heard of channels being used.  That said, I have looked at some FCC licensing data that indicates that railroads have locations where they have been licensed to use a splinter channel or channels if they choose to do so.  I must re-emphasize that the whole railroad radio and communication system is in flux.  A decade ago, railroads were planned to be converted to NXDN digital by now.  PTC and other forms of data transmission to an from trains has changed all of that.  I've heard some rumblings that the railroads are getting concerned that, if they do not use the splinter analog channels, then the FCC may assign those channels to other radio spectrum users at some point.  Amateur radio users have some of the same concerns.  As amateur radio users have declined, the FCC has come under increasing pressure to carve chunks off of their assigned frequency spectrums and re-assign those to other radio spectrum users.

K3HX Wrote:
-------------------------------------------------------
> I have used the Icom 2720-2730 series of duo band
> radios for many years with
> good results.

I've looked at the 2730 software. The software will accept the "splinter" frequencies (e.g., 160.4625 mHz), but I don't know if the radio will accept the frequency or "round it" to the 5 kHz tuning step.  If the radio would accept the splinter frequency from the programming software without modifying the frequency to fit the tuning step, it would mean that the radio could be software-programmed with the splinter channels functional in memory.  It would be interesting to know that.  Thanks.

By the way, the main reason that amateur radios stick to 5 kHz tuning steps is because the amateur radio channels (unique in the 2-way radio spectrum) can still be legally operated in "wide-band" mode instead of narrow-band.



Edited 2 time(s). Last edit at 09/17/22 14:10 by WW.

I have Yaesu FTM-400s in both of my trucks. I've had very good luck with them around town and on road trips. I've not done any specific test like others but have had good luck listening to the frequency of interest (when I'm out shooting) and use my scanner for other frequncies.

James Nelson
Thornton, CO
www.flickr.com/mojaveflyer



Edited 1 time(s). Last edit at 09/18/22 17:47 by mojaveflyer.

Thanks everyone.  I am looking at the Icom 2730A thanks to your input; if I go that route I'm willing to take a chance on the splinter frequencies, and would plan to get the RT programming software to "see what I get" attempting programming.
My next step is to work out antenna and radio mounting options as I am reluctant to drill holes in the brand new truck. I anticipate ordering the radio in early October.
Thanks,
-Alex
 

JUTower Wrote:
-------------------------------------------------------
> Thanks everyone.  I am looking at the Icom 2730A
> thanks to your input; if I go that route I'm
> willing to take a chance on the splinter
> frequencies, and would plan to get the RT
> programming software to "see what I get"
> attempting programming.
> My next step is to work out antenna and radio
> mounting options as I am reluctant to drill holes
> in the brand new truck. I anticipate ordering the
> radio in early October.
> Thanks,
> -Alex
>  
Go with a mag mount antenna.  A lot of folks will just pass the coax through the truck door -- maybe the one you use the least -- and close the door gently.  There is enought give in the weatherstripping that you shouldn't damage the coax cable.   One thing I like about this in my truck is if i have to go into a parking structure or something, i just get out, grab the antenna off the roof, stick the mag mount to the inside front of the bed, and not problem.  
Another easy solution if you want to use a handheld in your truck are the small antennal mounts that slide over the top of your door window glass.  These work good on the back seat door.  Not on the driver door window, as they may fall off when you have to roll a window down.  They are good for mounting one of hte accessory handheld antennae that are often 12-15 inches long.  They are a big improvement over the OEM antenna on the HT and of course raising it up a bit outside the truck helps as well.

Hi all -
GigaParts order has been placed! I am going with a lid mount NMO base (Comet) along with a 2m/70cm antenna (1/2 wave for 2m) to mount on the front hood, and a suction cup mount for the faceplate, and mounting the radio under the driver's seat.  I found that the 2022 Tundra has a pre-drilled hole through the firewall for accessories such as ditch lights, extra audio, etc and has spare fuse box terminals for this purpose.  So I can have a decent semi-permanent install without any holes.  (I might opt to screw the radio brain in to the floor but I'm going to start out not doing that & see how we do.)
Thanks,
-Alex

Another update.  I have the Icom 2730A installed in the truck now; was able to take it for a test ride over the weekend.  I am getting very good reception & selectivity, with only a bit of interference/static/etc near a local hospital (not unusual).  The VV/UU feature is one I will use a LOT, as it allows me to keep a primary channel and a scan list going at the same time.  In more remote locations I will leave one side on scan and the other on the HOT/EOT frequencies.  But in busier locations HOT/EOT will be endless chirping and I'd switch that side to the primary road channel wherever I am. 

I did play around with entering a splinter channel into the RT software for the 2730, and I got an error prompt stating that the frequency needed to be evenly divisible by 5000 or 6250.  I don't have a current requirement for splinter channels.  Hopefully that remains for some time...

I'm awaiting an aftermarket mounting bracket to arrive, which sits on the dash and will allow me to mount the Icom speaker and faceplate semipermanently. Once that's done I'll include a couple photos of the install.

Thanks again to WW and K3HX for the insight, very much appreciated. I can see that I will enjoy the 2730!
73 de KB3JOL
-Alex

^I figured that you would get that error--the 5000 or 6250 refers to either 5 kHz or 6.25 kHz spacing.  Since I already have good performing analog/NXDN mobiles in my vehicles, the only benefit of a dual-band radio for me is to hear the train telemetry channels up around 452 mHz UHF.  I can do that in one vehicle (my primary railfan vehicle) because I also have an older dual-band amateur radio in it in addition to the VHF analog/NXDN radio.  The other vehicle I don't use often for railfanning, so I just carry a dual-band portable in it to monitor the train telemetry stuff and use the VHF mobile to monitor the voice communications. 

I'm glad to hear that you are having good luck with your Icom 2730.  Over 20 years ago, I had an Icom amateur mobile in my vehicle that was super-sensitive, but had terrible selectivity.  Since then, Icom has really upped their game, I think.  My favorite commercial portable and mobile radios are Icoms.  I also have  Kenwood portable and mobile analog/NXDN radios that I like very much, but they do have some "quirky" keyboard functions, etc. that are just a bit more complex than the Icoms.  As I've posted before, the Icoms and Kenwoods are really close in performance--all excellent.  Those commercial Icom and Kenwoods have very good longevity, too.  All but one of them are nearly 10 years old or older and doing great.  The newest Kenwood is about 5 years old now.