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: [1]   Go Down
  Print  
Author Topic: Pickup Truck Topper Mount  (Read 426 times)
KG4DZA
Member

Posts: 4




Ignore
« on: May 01, 2006, 06:53:36 PM »

Hi all,

I'm considering attempting the following antenna installation would like some opinions:

Hardware:  2000 Ford Ranger pickup with a fiberglass topper.  Kenwood TM-D700 dual-band rig and a Diamond SG7500 UHF dual band antenna.  I also have a 2m no-ground-plane Larson but would prefer to be using the dual-band antenna to retain my 440 capability.

Use: RACES & Public Service, APRS

I'm considering using Diamond's UHF mobile mount cable assembly and mounting it through a 2' x 2' x 1/8" aluminum panel which is itself attached to the underside of the roof of the topper (for a ground plane and extra strength).  The panel will be grounded to the vehicle chassis.

I was told by Diamond that the metal on the roof of the truck might not be strong enough to hold the mount with the SG7500 (41" high).  Once the idea of some sort of underplating to strengthen the mount came up, I thought of moving the entire mount to the topper, which is more accessible and actually a few inches higher.  I also got the topper for free so have fewer qualms about drilling a hole through it.

Questions:

Is this installation overkill and should I just go out and buy some sort of lip mount or mirror mount?  If I go with this configuration, will I have corrosion issues between the UHF connector, the aluminum panel, and whatever metal components I use to mount the aluminim panel to the topper?

I'd really like to maximize performance for my public service work but if the difference between my topper mount idea and a lip mount isn't that great, I'll sacrifice some performance for ease of installation.  For safety concerns, and for participation in RACES, I'm not considering a mag mount.

I'm also still considering switching to an NMO mount but that issue seems to be more about quality and reliability rather than performance.  I'll address it once I figure out how I'm going to mount the antenna.

Thanks,

Eric, KG4DZA
Logged
K0BG
Member

Posts: 9878


WWW

Ignore
« Reply #1 on: May 01, 2006, 08:03:46 PM »

You need a much more substantial ground plane than a 2 foot square chunk of aluminum. The top of the cab is a better choice, even if you toss what you have and opt for a 1/4 wave.  If you want the best dual bander, look at the Larsen NMO 2/70 BK. Besides, the one you have is not what you would call a sturdy model.

Alan, KØBG
www.k0bg.com
Logged

K5LXP
Member

Posts: 4506


WWW

Ignore
« Reply #2 on: May 02, 2006, 12:11:02 PM »

For the setup you describe (ARES/RACES/APRS) I would go with at least two antennas on the cab of the truck, using NMO mounts.  For APRS there's no point in running anything greater than a quarter wave, the second antenna could be a dual band for voice.  Optionally you could consider a third mount for a 'spare' rig, one that could be used with a 2nd ham, public safety rig or scanner.  By using NMO mounts you can easily replace or exchange antennas depending on need.  NMO's are way stronger than the sheet metal you have to mount them in, and are the defacto standard for public safety communications.  Any concerns about them being 'unreliable' are unfounded.

Mark K5LXP
Albuquerque, NM
Logged
KG4DZA
Member

Posts: 4




Ignore
« Reply #3 on: May 03, 2006, 06:50:37 AM »

Thanks for the input guys.  I'm going to abandon the idea of using the topper and am going to install to the cab roof instead.  

'73

Eric, KG4DZA
Logged
Pages: [1]   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!