PMR446 walkie-talkie receiving noise from Surf - help!

[joecuba]

Running some PMR446 walkie talkies in the Surf recently, and noticed that the Surf puts out interference that seems to start above ch8, then ch8 and falling through 7 6 etc to ch 2 and then stays there.

There is no specific signal, it just opens the squelch when I am scanning.

I noticed the interference starts when the ignition is on, without the engine running.

Can anyone help me silence it so I can scan on PMR frequencies?

[Vultch]

Is she a diesel or petrol

[joecuba]

3.0 Diesel SSR-G

[Vultch]

more questions are you powering the scanner of the Surfs 12v system or is it on batteries, trying to see if interference is carried by pwr lead

[Apache]

Possibly a harmonic of a processor clock in the ECU. Pull the plug on it, then turn ign on, see if it goes away.

Not many other sources of noise on a Surf. I ran a scanner on my truck for a long time with no issues, but was using a whip antenna fitted on the spare carrier so well away from the Surf's minor amount of electronics.

Incidentally, it wont be easy to sort out! If it does turn out to be the ECU, would be worth attaching a bit of braid from the case to the body, and if you're feeling really nerdy, wrap the ECU loom with copper tape, earthing it near the ECU. Even clipping a few ferrite cubes over the loom near the ECU end might help if the noise is being radiated from the ECU cables.

[joecuba]

Thanks guys.

I am powering it on its own batteries. Tried two types of PMR446 radio, both pick it up. Interestingly, the more advanced PMR radio I have also picks up something on ch 16 (other radio only goes to 8), which turned out to be the CD player!

I had a h/h scanner a few weeks ago in the truck, and I don't remember a problem with this, but then I think a scanner is less sensitive at these particular frequencies. Yes I did have the PMR frequencies programmed in!

Apache - where is the ECU? I am reasonably versed in grounding / electronics, so trying the things you mention shouldn't be a problem once I know where the ECU is :-)

Thanks!

[Albannach]

[Apache]

If its the same as a 2nd gen, its in the passenger side kick panel.

Yesh, CD player will do it too! Lots of nasty little sharp edged clock pulses whizzing around!