What's your thoughts on an all bander for a mobile?

Discussion in 'On the Road' started by KD0PEZ, Jul 12, 2014.

ad: L-HROutlet
ad: l-rl
ad: abrind-2
ad: L-Geochron
ad: Left-3
ad: L-MFJ
ad: MessiPaoloni-1
ad: Left-2
ad: HRDLLC-2
  1. KD0PEZ

    KD0PEZ Ham Member QRZ Page

    Long story short, a few months ago I was mandated to leave my home in Missouri and drive 500 + miles south to Texas for schooling. (Air Force) At the time I threw in a Yaesu FT857 and used a Comet VHF/UHF dual bander as well as a Little Tarheel II to run the HF side. All of this in my 2004 Tacoma. (it has the metal bed)

    While on the road, trying to work HF seemed like it would be a challenge. In trying to ensure I didn't go out of my privileges, I found trying to eye the LCD while keeping my eyes on the road was difficult. Needless to say I decided against trying to work any DX while driving.

    While stopped wasn't much better. Even at full power (100W) and with the optional 56" whip on the Tarheel (stock is 32") and grounds to the bed, cab and frame to the ground on the Tarheel.....I STILL had a hard time working DX. I did manage to make a few contacts but not many.

    I didn't hear much repeater activity in northern TX, and on the road I used the nat'l 2 M calling frequency maybe 3 times.

    Then I got to thinking, I don't spend much time in my mobile anyways, and I have my base station that gets out so much better (Kenwood TS-2000 and an Outbacker), I started to wonder why even have an all bander for mobile.
    So what's your take on an all bander for the road?
     
  2. N0IU

    N0IU Ham Member QRZ Page

    Its definitely not for everybody and this statement tells me that it is probably not for you... at least not at this point in time.

    OTOH, I used to have a regular CW rag chew with a guy who could send at 30+ WPM... while driving! I can send that fast sitting at a stationary desk, but in a car at highway speeds... no way! I have also talked to a guy who sent CW while mobile... on his motorcycle! Definitely not for me!

    Have a good time at Lackland.
     
  3. KD0PEZ

    KD0PEZ Ham Member QRZ Page

    Thank you Scott. The last time I was at Lackland, was early 1999. There's more than 1 base in Texas. I was actually at Sheppard.

    Yeah I am thinking I am going to sell off my mobile set up. I could use the $ for my classic Chevy Nova....putting on some go-fast goodies.
     
    W7XV likes this.
  4. K4KWH

    K4KWH Guest

    As was noted. all band HF isn't necessarily for everyone. If you ARE serious about mobile HF, then the general rule is as Don Johnson put it in his books on HF mobile. "It takes a big UGLY(?) antenna to make those DX contacts from the mobile." (para) I'll add to that...perhaps a few arguments from the XYL, too! Seriously, there is are reasons for what is sometimes less than stellar performance from the mobile, and, again, it mostly centers around the antenna. Mobile operations are a compromise from the "git-go" because you are necessarily scrunching down that 100 foot (more or less) antenna into a short vertical which may, due to cosmetics, may involve a small tightly-wound coil and a long whip. The small coil with small diameter wire causes loss, and these smaller antennas generate heat that would normally be your signal. That puts your signal at several DB below the floor of what your intended "victim"....I mean, DX;) wants to hear. So what to do. And it involves several factors. $$$$, i.e., just how much you are willing to invest to produce that big mobile signal, just HOW much "ugly" you are willing to endure, how much yelling from the XYL your earplugs can filter out!:D

    Everybody has solutions that work "best" for his own needs. Generally, IMHO, the best mobile antennas are those screwdriver-style antennas with a 3" coil and at least #14 wire @ 8 TPI.....or larger. However, there ARE physical limitations in size and weight that your vehicle will endure. But by choosing the largest screwdriver you can install, given any restrictions, you CAN have a quite reasonable DX signal out there from your mobile. Screwdriver antenna were the best thing to happen to HF mobile in the last 25 years and they make it possible to do highly successful operations from your vehicle. Another example is, temporary stationary ops. You can take a long wire and make a 'half dipole' for your screwdriver. Using a 3/8" X 24 TPI bolt, you can screw one end of this half dipole into the screwdriver, then sling this random length wire (restricted only by the range of your Screwdriver) into a tree, supported by a rope and and insulator. VIOLA! You now have a "stationary" field station with base station performance, and horizontal polarization that would be compatible with other stations at higher frequencies. For 10 Meter stations operating in the local area on verticals, you could simply switch to the normal whip. This makes mobile ops FUN and exercises one's imagination in grabbing for those DX stations. Me, I used it this method during Hurricane Floyd on an Air Force mission, operating on CAP frequencies from a comm. van. I got quite a few compliments from the Mission staff over the excellent mobile communications provided from that field van!:D

    Gud luck with your mobile ops.
     
  5. N3AWS

    N3AWS Ham Member QRZ Page

    Since this seems to be an USAF oriented mobile thread, I feel obligated to jump in---

    At 24 years active duty, I have operated mobile from: 1999 Miata, 2002 Itasca Sunstar RV, 2010 KIa Soul and 2014 Kia Soul. Rigs included Icom 706 MKIIG, Icom 756 Pro II, and Yaesu FT-817. Activity has encompassed: state QSO parties--80%; general operating VHF--10 %; VHF contests--5 %; and 5 % other. I think a minimal rig such as an Yaesu FT-817 is a worthwhile investment. YMMV.

    73,

    Jim N3AWS
     
  6. KD4UPL

    KD4UPL Ham Member QRZ Page

    When I was an OTR truck driver I bought a Yaesu FT-100D and various ant. thinking I was going to do a lot of mobile HF radio. I discovered that tunning the radio, adjusting the DSP, RIT, NB, etc. took a LOT of attention. I didn't like being that distracted form what I was supposed to be doing; guiding 80,000 pounds down the highway at 70 mph.
    I stick to only VHF/UHF FM mobile now. Monitoring or scanning a few repeaters is much easier to manage while driving.
     
  7. W8LM

    W8LM Ham Member QRZ Page

    The true mobileers are using antennas in excess of 8 feet in length. Top hats and such.. I have had great sucess with an 4" Hi-Q mounted at the edge of my pickup bed rail and the antenna tip at 13 feet 8 inches, to stay under the interstate 14 foot overpass limitation. My top hat is home brew and looks like a 3 foot diameter clover leaf made of .100 stainless steel wire looped into a 1.5 x 3/4 inch hexagon aluminum hub.

    Years ago hams would use a copper toilet bowl float as an end-top to their whip. Some hams even used a cluster of 3 copper toilet bowl floats. and bumper mount an antenna that the length would be 12 feet tall. These days no one uses large ends on their antennas. I undertood that it increased bandwith and effencies. No one tries to top load a shortened vertical either. Top loading is favored by commercial broadcasters.

    BTW on 160- 80-40 meters there is quite a difference between an 8 foot and an 12 foot loaded vertical..To me an Yaesu AT-120 is as close to an isotropic radiator you can get mobile.. well, isotropic radiators radiate.. That's why you can load the bed springs with a tuner...

    Just try a 100 watt light bulb.. nothing else and you can easily make contacts... Years ago there was an "italian vertical" It was a vertical with a 100 watt light bulb across it's feed point..... it loads all bands- guys would make contacts all the time hundreds of miles with one...The vertical radiator was 16-17 feet.. resonate on 20m...and claim "no radials needed".. you can make one for under $5...and work the world..

    The best antenna I ever used was 1650 foot centerfed long wire flat top at 70 feet. It was made of 3 strands of #12 copperweld twisted. at the feed point was a B&W air wound 4:1 balun...Not recommended for apartment dwellers. The Balun was in a box about 2x2x2 feet. and fed with RG8/U. no antenna tuner was needed 80-10..
     
    W7GST likes this.
  8. N4BOZ

    N4BOZ Ham Member QRZ Page

    As a new HAM, I've struggled with the question myself -- but have recently come to the conclusion that a dual-band UHF/VHF mobile unit is what is in my future. First, I have no experience yet doing any HF stuff -- so I don't know what I am missing ... but secondly, the antenna size, specs are not something I want hanging off an of my vehicles... even if just to dabble some in HF while mobile.
     
  9. ON4AVT

    ON4AVT Ham Member QRZ Page

    I am using the ATAS and the FT 857 D,Works great,automatic tuning ,always swr oké
    Screen is smal yes,thats way you most not mounting it a 2 meters from your eyes .
    willy
     
  10. K6CLS

    K6CLS Ham Member QRZ Page

    agree with the comments about driver distraction. even on the wide open roads in Texas, please don't endanger yourself and everyone trying to operate HF mobile.

    that said, portable (not mobile) HF is quite do-able. skip the screwdriver antenna. get an MFJ 3-magnet magmount and a set of hamsticks for the bands you want to work.

    I have had many excellent and enjoyable QSOs with hamsticks and the magmount. you will too.
     

Share This Page