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: SMALL 60M MOBILE ANTENNA???  (Read 7270 times)
N3OX
Member

Posts: 8854


WWW

Ignore
« Reply #30 on: January 28, 2011, 08:38:42 AM »

Did someone mention that max power is defined on 60 meters in terms of ERP? 

That could get expensive because you have to get an antenna that will handle the power, but it's a good point.

You get a "free 3dB" if you have a hundred watt rig... guess if you got one of the 200W rigs out there you could get a free 6dB provided you have an antenna that will handle that.

Had some guy in these forums talking about running a RM Italy amp on 60m to make up for the bad mobile installation but that sounds like a terrible thing to do on 60m, even more so than the other ham bands.  I don't know how carefully we're actually being watched in terms of the stated bandwidth restrictions but we really can't tolerate off-channel splatter if we're going to be responsible users of the band.


Logged

73,
Dan
http://www.n3ox.net

Monkey/silicon cyborg, beeping at rocks since 1995.
K0OD
Member

Posts: 2546




Ignore
« Reply #31 on: January 28, 2011, 09:19:59 AM »

60 meter mobiles seem to get out really well.  I hear lots of them giving their power as 100 watts. And many could probably run even more legally.  Too, many home stations run gawd awful antennas on 60... like 40 meter dipoles. So mobiles are quite competitive there.

Note that the 50 W ERP limit should soon go to 100 watts ERP, along with other enhancements such as (channelized) CW and two types of digital.  Waiting for final approval by the FCC. 
Logged
WX7G
Member

Posts: 5985




Ignore
« Reply #32 on: January 30, 2011, 08:04:35 AM »

I don't have the ARRL Antenna Compendum 7 so I can only guess at the mobile wire grid model. If it's like all the others I have seen, the antenna current shown on the vehicle appears to be less than the whip current because the current per wire-grid segment is only a fraction of the whip current. The vehicle current of each vertically oriented segment must be added together to obtain the total vehicle current. The vehicle current MUST equal the whip current; the current on each side of the feed node MUST be the same.



Logged
W9CN
Member

Posts: 45




Ignore
« Reply #33 on: February 01, 2011, 06:25:17 PM »

As someone who has attempted to run 60 meters out of my 02 Cadillac DTS let me point out that the internal buss that ties in the 20 or so computer modules together that run every aspect of the vehicle has a 5 MHz clock rate which didn't enjoy 60 meters in the least.  In fact when I tried it it lit up every warning indicator and light on the dashboard like a Madam LaRue pinball machine on Tilt and put the engine into "limp home" mode.

I had to pull over and restart the car.  It reset the both trip odometers, the car radio presets, MPG calculations, fuel used and just about every one of the user defined information settings..  My Cadillac dealer thought it was very funny after he explained that the buss clock frequency was 5 MHz..

I run 40M just fine.  No problem with 20, 15, 10 or 6 either.  But 60 Meters wasn't happy in the least.

Best regards and '73,

Mike Pappas
W9CN
Logged
KC8IUR
Member

Posts: 156




Ignore
« Reply #34 on: February 02, 2011, 04:59:47 AM »

That's pretty awesome. Going to my Toyota dealer today for a service. I'll ask what their clock rate is while i'm at it.
Logged
K0BG
Member

Posts: 9867


WWW

Ignore
« Reply #35 on: February 02, 2011, 08:43:53 AM »

I suspect the problem is common mode on the coax, and perhaps an inadequate choke on the motor leads. At least, that is where I would start.
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!