Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement
About eHam.net

   Home   Help Search  
Pages: Prev 1 2 [3]   Go Down
  Print  
Author Topic: HF mobile, which rig?  (Read 10357 times)
W2RI
Member

Posts: 57




Ignore
« Reply #30 on: January 19, 2011, 08:03:57 AM »

The Icom 7000 is a great rig. As James mentioned, it can run hot, but it can show the internal temperature on the main display so you can keep an eye on it. Unless you're doing a digital mode at full power for a long time it shouldn't be an issue.

I'd recommend you join the Icom 7000 mailing list on Yahoo : http://groups.yahoo.com/group/ic7000/

Good DX !

-- Brian
Logged
ZENKI
Member

Posts: 997




Ignore
« Reply #31 on: January 21, 2011, 01:22:54 PM »

I would go with the TS480HX, the extra 3db is well worth it mobile. Try and improve your antenna system by 3db! Using a TS480HX you will  need to run at least a 1kw amplifier to notice the difference. I  have a 1KW mobile amplifier installed, now with the TS480HX I hardly turn it on!

As for the antennas. All these expensive screwdrivers are big heavy contraptions. They are all very expensive, you looking at investing 1000 dollars or more just in an antenna system. You also bolting on a massive heavy contraption to your vehicle just for the convenience of band changes.  If I was a serious low band mobile dxér I might consider using these big heavy  contraptions.
For 20 and 40 meter dxíng there are many choices that are as good. Even a properly installed Hamstick in the center of the  roof well grounded will just about be equal with these big heavy muscle antennas.

I personally did not think all that effort and heavy hardware was required. The way most people install their screwdriver antennas they are just wasting performance and money. My homebrew  helical antenna mounted in the center of the roof has beat many of these  "super space age and mil spec" screwdrivers in shootouts and pileups running barefoot. Because they are big heavy contraptions most people do not install them correctly. Its far easier doing a proper install job on a light antenna  than a big heavy one. Thats why most people  install these big screwdrivers poorly because they are big fat heavy contraptions.

I just homebrewed  the best center loaded antennas that work as well and better than most screwdrivers. I like 20 meters and 40 meters mobile and  have monoband  coils that work very well. I also  have a  homebrew helical wound antenna that when mounted on top of the roof performs as well as my mid mounted  12 foot long center loaded whip and works better than most screwdrivers.

The only screwdriver I would consider buying  or building would be  the one made by VE6AB as seen on K0BG's web page. This looks like a well engineered screwdriver that could be lighter that the 20 pound Scorpion which stings you in many ways.  I wish VE6AB would produce this antenna commercial and offer a Titanium version! When you drive on roads with no speed limits the last thing you need is a 20 pound antenna exerting lots of pressure on your expensive car, it would be even worst if the antenna broke its mount.  I have driven with my  light loaded coil antenna at well over 200Kph without any problems. Screwdriver antennas seem like a good idea for MAC trucks and Hummers!
Logged
K0BG
Member

Posts: 9901


WWW

Ignore
« Reply #32 on: January 21, 2011, 01:51:57 PM »

The antenna you're referring to was made by Jerry Clement, VE6AB. I haven't ask him specifically about what it cost to make, but knowing how it was made is enough. I suspect if it were made commercially, you'd be paying in the neighborhood of $2,000. The bottom portion is spun closed, and not everyone has the equipment to do that sort of work. Probably the most unique part if the operating motor, which is a linear actuator, mounted outside the antenna itself.

As for the 3 dB from your antenna.... Actually that is quite easy to do on the average vehicle installation. While we all think our specific install is super special, the fact is, most aren't. I've seen screwdrivers installed where there was no motor lead choke to be seen, which makes you wonder about the rest of the install. The same goes for common mode chokes.

Another issue, universally overlooked, is the generated SNR; both transmit, and receive. It is easy to present a case wherein one dB increase in transmit power can make the difference between a QSO, and not. Reducing localized RFI is just as important, but is often overlooked as well.

It all boils down to just how far you're willing to go. If an ATAS mounted on a K400 is your cup of tea, that's great, but it isn't mine!
Logged

W3LK
Member

Posts: 5639




Ignore
« Reply #33 on: January 22, 2011, 12:37:01 PM »

Screwdriver antennas seem like a good idea for MAC trucks and Hummers!


I drive neither; I drive an '03 Ford Windstar with a High Sierra HS-1800Pro on it and have no problems with anything. There's two photos of the installation on Alan's photo gallery. It's been on the vehicle since it was new, and on a similar Windstar for two years before that.

73,

Lon - W3LK
Naugatuck, Connecticut
Logged

A smoking section in a restaurant makes as much sense as a peeing section in a swimming pool.
WZ3O
Member

Posts: 43




Ignore
« Reply #34 on: February 07, 2011, 01:15:34 PM »

OK, time to "wade in" with my 2¢s..........

I own an IC-7000, great rig but a bit pricey for mobile....will do anything you ask, but is a compromise on 2M/440......

The Kenwood TS-480 (SAT/HX) another nice rig, had one liked it, a bit big regardless of separation capability?.....

The Yaesu FT857D with separation kit is, IMHO, the most "bang for the buck", with many convenient mounting options ("read" small spaces, etc). Also had one mobile, nice small package with tons of features on all bands... Decent HF, 2M, 440,etc.....Only needed one rig in mobile.....

OBTW, all but the 480 SAT need a tuner or resonant antenna........I'm sure you knew that....

And "YES", to paraphrase a Real Estate saying, "antenna, antenna, antenna"............& WELL GROUNDED!!!!!!!

Have fun, enjoy DX mobile, I do, it's cool...... Wink
Logged
K0BG
Member

Posts: 9901


WWW

Ignore
« Reply #35 on: February 12, 2011, 04:19:47 PM »

Gee. I've been at this mobile thing for about 40 some years. In all of that time, I have never seen a grounded antenna that radiated! Oh! Oh! Sorry! Maybe I misunderstood.

Any antenna will operate properly without any ground whatsoever! If I take a rig out to field day, string up a vertical with elevated radials, power the radio with a battery, it will work very well. This said....

I have to assume you mean that the antenna in question has to have a ground plane under it. Oh! Oh! Maybe not!

What I think most people mean is, the mount (!!) must be grounded, even if it is attached to a trailer hitch! Well, even if it is, that in itself doesn't mean adding a ground wire from the mount, back to the frame of the vehicle is a direct replacement for an adequate ground plane under the antenna! Well, it isn't!

The real secret is very simple. It is the metal mass directly under the antenna, not what's along side, that counts!
Logged

N6PG
Member

Posts: 79




Ignore
« Reply #36 on: February 19, 2011, 12:00:42 AM »

I think you can't go wrong with any of those radios.  Whatever is the first "good" deal on the used boards might be a good decider.  I have the FT-857, and I'm very happy.  I would recommend the mic with the DTMF pad.

I agree that the antenna is very important, but don't let it distract you too much.  As someone else pointed out, many hams have been making contacts with inefficient antennas for a long time.

When I got my 857, the owner GAVE me his ATAS-120.  You can read the reviews to see how much people don't like it... but you know what... I mounted it up high on the car, gave the antenna mount a good ground, and I have talked to Japan, Indonesia, the Falklands... all on that "terrible" antenna.  The good news is that it's such a low profile antenna, that my wife doesn't mind it on her car.  It isn't an eyesore.  The 857 adjusts and tunes it automatically... and it does the job.  One antenna on the car for 40 meters to 440 Mhz!  I know you can't defy physics, so it isn't the best across all bands, but it certainly works.

BTW- The 857 only draws .5 amps on receive.  That's a lot less than the icom.  You can take the 857 camping and set it up with a buddipole antenna and one of their great power pack batteries and operate for a long time.

I think any setup will provide you lots of fun... but you will always be looking at other setups and wanting to change what you have!  Let us know what you end up with.
Enjoy.
73's
Scott
« Last Edit: February 19, 2011, 12:36:59 AM by N6IMM » Logged
AF6WI
Member

Posts: 105


WWW

Ignore
« Reply #37 on: February 19, 2011, 01:25:16 PM »

As another has said, I don't think you can go wrong with the radios mentioned. I use a TS-480SAT, which sits on my desk at home when I'm not mobile, and which works fine when I'm out camping with the radio.

I use a Tarheel screwdriver. I find it puzzling to see it referred to as a heavy contraption, but to each his own.

My suggestion is to see if you can find a radio which gives you multiple uses. I use the TS-480 as my home radio, my on the road radio, and my camping radio, so I get more use out of it than just in the vehicle. The Tarheel works fine, although it's somewhat directional since the antenna is not mounted in the center of my roof. It's mounted in the back and points more towards the front, over the metal roof. I live in California, and I've used it on my vehicle to work stations on the East Coast (Rhode Island, Florida, for example), as well as points in between.

All radios and all antennas are compromises, so you have to find the compromises that work more nearly in your favor and that sacrifice things you care less about. The TS-480 is bigger, but it dissipates heat better. The screwdriver may not be as good on any particular band as a dipole cut for the band, but I just push a button in the cab to tune the antenna to a different band where I can reach out and talk with someone. I don't have to stop, get out, switch sticks, etc. That's a compromise I'm happy with, given that I can work stations all over the US from my vehicle.

I have the Tarheel Model 100, and it doesn't seem heavy to me, although it is of course heavier than a stick of whatever brand tuned to a specific band. I have no objection to those, but I'm happier changing bands from the cab on the roll if some particular band is crappy and another is hot - I just search while on the road. I've never thought of my Tarheel as a heavy contraption, but that's because I get my intended use from it. Others may not; your mileage will vary.

If I may suggest, stop thinking about it and go buy stuff. Get on the air and see what works for you and what works against you. Then you'll be here giving your advice. :->

Everyone tells you what works for them, and then assumes it will work just as well for you. That's sometimes not the case.
Logged
K0BG
Member

Posts: 9901


WWW

Ignore
« Reply #38 on: February 20, 2011, 07:26:36 AM »

Quote
Everyone tells you what works for them, and then assumes it will work just as well for you. That's sometimes not the case.

I'd say it isn't the case 90% of the time. If you look at the specs for all of the late-model made-for-mobile transceivers, they're very close. What difference there is probably won't be noticed by the average operator. Where the difference really shows up is in the use of the radio. I personally find the FT857 a difficult radio to operate (yes, I have owned one). The IC7000 is a bit better as far as the menuing goes, but it too needs some improvement.

The same things can be said for antennas, and how they're mounted. Everybody seemingly brags about their low SWR, the DX they've worked, shootout results, and similar mundane references.

However, as alluded to in the quote, your seemingly identical install may indeed end up as nothing more than a static receiver! It is the classic example of effort vs. results, and too darn many just won't extend the requisite effort.
Logged

Pages: Prev 1 2 [3]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!