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: Issues with SRS and other computer controlled equi  (Read 647 times)
AB2MH
Member

Posts: 263


WWW

Ignore
« on: January 09, 2004, 03:38:18 PM »

My '04 Accord has quite a few computer controlled items as standard equipment, including the engine, climate control, SRS with side curtain airbags, Navigation system and climate control.  

I'm ordering the rig (Either Icom 746MKIIg or Yaesu FT-857), HF and VHF antennas very soon for the car and will be installing them, but I don't want to endanger myself or cause my car to malfunction while operating mobile.  I was thinking of mounting the radio in the trunk and mounting the control head up front.  That way the coax going to the antenna could be short to possibly reduce any problems.

Does anyone have any experiences or advice they'd like to share?  The antenna will most likely be going on a trunk lip mount.

Oh, another question while I'm at it - does the 746 have a bracket so that the rig's control head can be mounted on a DIN slot like a standard car stereo?  What about the cable leading to the rig?  In all the ads, brochures and pictures I've seen, the separation kit cable comes out of the side of the control head.  Can it come out of the back of the control head so that it can be hidden away?

Ryan (AB2MH)
Logged
AB2MH
Member

Posts: 263


WWW

Ignore
« Reply #1 on: January 09, 2004, 03:40:44 PM »

Just a minor correction,

It's the Icom 706 not the 746.  I already have the 746 in my shack, and it's too big for the car!
Logged
AA4PB
Member

Posts: 12892




Ignore
« Reply #2 on: January 09, 2004, 05:26:15 PM »

Provided the antenna is properly installed and grounded you shouldn't have any problem with running the coax up front to the radio. I've had both a TS-50 and a IC-706MkIIg mounted up front, not 12-inches from the air bag computer and have not had any problems.

There is also no problem with mounting the radio in the trunk if that's what you prefer. The issue there will be getting the power from the battery back to the radio. Voltage drop in the cable can be an issue when the radio is drawing nearly 20A peak current. You'll need to use some heavy cable, probably #6.

Another problem I read about some having with the 706 remote is the remote cable picking up RF and causing problems with the radio. You may need some ferrite beads over the cable.
Logged
K0BG
Member

Posts: 9878


WWW

Ignore
« Reply #3 on: January 09, 2004, 07:50:37 PM »

I do not dispute Bob's scenario, however....

I have an Acura coupe with basically the same equipment, and I have a few suggestions with respect to your installation.

First, strap the trunk and hood on both sides, strap the doors, strap the exhaust and tail pipes, and buy yourself a bunch of split beads (mix 43). the beads should be installed on the nav system leads in the trunk, on the COP units, cooling fans, fuel pump (you'll need about 4 here), and put two or three on the AM/FM radio  lead which runs in the right hand wiring (kick) channel.

Even with all of this, you're still going to have a problem with the nav system (it'll flicker when you're talking), and the AM/FM radio should be turned off while you operate.

If you need to bring cables into the passinger compartment, there is an unused grommet 2" toward the passenger side and about 2" above the accelerator pedal. You can see it from both sides of the firewall. Just make sure you tie the wires back so they do not interfere with the accelerator pedal and cable.

If yours has a TCS (traction control system), you'll need to bypass its computer as well. On the Acura (and I believe the Honda as well), it is above the glovebox and you'll need to remove the door and box to get to it.

Have fun....


Alan, KØBG
Logged

AA4PB
Member

Posts: 12892




Ignore
« Reply #4 on: January 09, 2004, 10:09:56 PM »

Wow! I have not experienced that much RFI problem, Alan but I don't have a Honda either. Do you think that it is related to the location of the radio or is it picking up the RF from the antenna - or perhaps RF currents in the body. I figured that with a proper antenna installation there should not be much RF radiated from the coax shield or the radio case so there wouldn't be any benefit in terms of RFI to mounting the radio in the trunk. What is your experience?

Logged
K0BG
Member

Posts: 9878


WWW

Ignore
« Reply #5 on: January 10, 2004, 09:18:38 AM »

Bob, I do have a little RF inside the trunk as the lead from the auto-coupler to the back of the ballmount is about 5 inches long. The trunk lid is DC grounded, but it presents a poor RF ground, and one strap wasn't enough. I added two more to the engine as well which lessened the ignition noise by about one S unit.

Once I strapped the doors and the hood, most of the RF problems went away. The Nav system is still a problem as the antenna is in the back glass along with the AM/FM radio antenna. Funny thing. If you turn on the back defroster, the RF to the Nav system goes away.

I haven't been under the car yet, so I only have the one strap on the tail pipe which didn't do much.

The biggest problem I'm having is the arcing around the ballmount which I'm in the process of fixing once and for all with a slab of Delrin which cost me nearly $100. I think this is the source of some of the problem.

Alan, KØBG
Logged

AA4PB
Member

Posts: 12892




Ignore
« Reply #6 on: January 10, 2004, 11:16:52 AM »

Alan,

How about an RF bypass capacitor from the defroster power lead to ground? Perhaps when you turn it on it is seeing a low impedance to ground back thru the power source but when its off the lead is "floating" and picking up and distibuting the RF.
Logged
AB2MH
Member

Posts: 263


WWW

Ignore
« Reply #7 on: January 10, 2004, 09:34:36 PM »

Thanks for all the suggestions.

A few more things:

Thick wire to the trunk is definitely a possibility if I decide to install the radio in the trunk.

The passenger compartment is also a possibility, but does the 706 fit in a DIN slot?

If it does that will be great because I can just get the audio attach and replace the CD storage compartment with that, and mount the rig in there.

You said the nav display will flicker, do you mean the nav display will be unusable when I transmit?

By strap, I assume you mean using braids to electrically connect the components to the chassis to reduce noise?

Thanks in advance for all of your help guys.
Logged
AB0RE
Member

Posts: 293




Ignore
« Reply #8 on: January 11, 2004, 03:02:09 AM »

On my 02 Accord the airbag/SRS computer sits underneath the cubby-hole beneath the radio.  I used to have a ground strap connect very close to the airbag computer and at one point tranmitting with 75W on VHF caused the airbag computer to malfunction.  It had to be replaced by the dealer.

I haven't installed HF in the mobile yet so I can't comment on noise, etc.

The power supplied by my 02 Accord is pathetic (noisy).  I tried some ferrite chokes under the hood and a huge noise filter.  I suspect the noise filter is doing all the work as I all but gave up on the ferrite chokes under the hood.

73,
Dan / ab0re
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!