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FTM-350 RF Interference Issue

depark

W9WDX Amateur Radio Club Member
Feb 17, 2010
222
16
28
Kelowna, BC
I have a question for the group. Can anyone tell me how I can I stop my radio from locking my van doors every time that I key the mike when transmitting on high power. It also does it when the APRS beacons:oops:. It is dam annoying but kind of funny at the same time:p. Any suggestions would be greatly appreciated.

73 Darryl VA7DTP
 

Do you have it hooked directly to your battery? What type of antenna mount are you using? Have you put and ferrites on the power leads and the transmission line?
 
The radio is connected to the battery. I made a custom 12 gauge Stainless steel antenna mount which is bolted and screwed to the fender. I haven't tried ferrites yet. Where would I put them, close to the radio or to the battery and antenna?

73 Darryl VA7DTP
 
Does it lock all the doors, or just one? You're probably going to have to find the door lock circuit board, or at least the power wires feeding the board. Try the typical fixes for problems like this: run some ground strap, wrap the power lines around some ferrite, and add a .01 ceramic disc cap from pos to neg. It will take some experimenting to find which wires are picking up the RF, but you should be able to get rid of the problem once you locate it.
 
Does it lock all the doors, or just one? You're probably going to have to find the door lock circuit board, or at least the power wires feeding the board. Try the typical fixes for problems like this: run some ground strap, wrap the power lines around some ferrite, and add a .01 ceramic disc cap from pos to neg. It will take some experimenting to find which wires are picking up the RF, but you should be able to get rid of the problem once you locate it.

It locks all the doors. What is a .01 ceramic disc cap? I have never heard of that and where do you put it?

Darryl VA7DTP
 
A disk capacitor is one of those capacitors that, well looks like a disk as opposed to the ones that look like little cans. You put it across the the positive and negative leads. I'd start by putting a couple ferrites at the antenna as close as possible, and a couple on the power leads as close to the unit as possible. Make sure the radio has a good ground, an rf ground 1-2" copper braid is the best.

Other areas that could be considered, ensure that the doors are actually grounded to the chassis or body (in a unibody) again rf ground 1-2" copper braid is best as opposed to DC grounds. I'd start at the drivers door which usually has the master switch which locks all the doors.
 
If you have remote entry, you might never be able to isolate the system well enough. The receiver antenna will still pick up the signal. Might be a tough one.
 
I do have a remote starter/entry with 3000 foot range. I hope that it's not that. I guess this means a lot of trial and error ahead of me.:( Thanks for all the suggestions.

73 Darryl VA7DTP
 
If it's an aftermarket definitely a possibility, but as it just locks the doors wouldn't be my first choice as the doors need a code to be activated not just a random radio signal.
 
I'm reviving this thread - been doing some searches for similar issues to mine. I installed my 350 in my new 2011 4runner. Here's the setup:

- power directly to battery (negative post is already grounded to chasis)
- radio sits under seat (not grounded)
- head near the dash/radio
- Antenna routed through back, mounted on a diamond mount, using thin coax cable

Symptoms:
- When I'm stationary (with or w/o engine running) everything seems fine.
- When I start moving, I get horrible static on all stations except those that are very close (within a few miles). It can be as slow as 5mph. No change in static with changes in speed, and no "whine" heard either. Just very bad static that I can't make out what anyone is saying.

Tried the following:
- Tried a whole new antenna cable, mount, and antenna (and location) - no change.
- Called Yaesu, and they suggested grounding the radio from one of the bracket mounts to the car. Also suggested I get an antenna analyzer to measure SWR and impedance. But with two different antennas with the exact same issue, I'm thinking this probably is not the issue.

Some of the ideas posted in this thread include capacitor across the +/- power leads (where would I do this - near the battery or where the power goes into the radio?

Ferrite cores - how big and it wasn't totally clear where to put this - on the power cables near the radio or does it matter? How many time would I wrap it around the core? For the antenna, would I wrap the cable around the core? How many times?

Thanks for any input!
Bill
 
Some of the ideas posted in this thread include capacitor across the +/- power leads (where would I do this - near the battery or where the power goes into the radio?

Ferrite cores - how big and it wasn't totally clear where to put this - on the power cables near the radio or does it matter? How many time would I wrap it around the core? For the antenna, would I wrap the cable around the core? How many times?

Thanks for any input!
Bill

I can answer some of these. Install a capacitor near the battery. Farrite cores go on the power leeds as close to the radio as possible. Cores also on the coax as close to the antenna as possible. For the cores I used the type that clamp around the wires. I used 3 at each location. Also ground the radio chassis. It is a place to start.
 
I can answer some of these. Install a capacitor near the battery. Farrite cores go on the power leeds as close to the radio as possible. Cores also on the coax as close to the antenna as possible. For the cores I used the type that clamp around the wires. I used 3 at each location. Also ground the radio chassis. It is a place to start.

Thanks, will try it out. Did you ever solve your interference issues?
 
Not yet, I still have grounding to do. It works well at medium power and with all the repeaters in the area I usually have it set to low anyway. I just haven't run into the problem of having to use high power yet. I'm sure that it will come back to haunt me when I want it and can't use it though.:D Maybe I should do it soon.(y)
 

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