HF interference from speedo fix?

I think you will find it is the oil pressure sender, that was what it was on all my cruisers.
Stays quiet till the oil pressure changes and then starts making a whirring whining noise. Can be cured by putting a capacitor between the centre terminal and the case of the sender. It is on the side of the block towards the rear of the engine on passengers side, tin shaped thing about 30mm dia.
you can prove what it is by unplugging the suspect unit and going for a drive.
you will also find the wiper motor, GPS cpu and even the UHF CB will cause noise.

Tony,

Can you describe what the noise sounds like and on what frequencies on the HF,

I have a 105 series and a Codan HF and I get a 'beeping' noise which varies only with the speed of the vehicle, irrespective of engine revs, so it's not engine, alternator or anything else causing it. The beeping noise is faster than wheel rotation so I figure it is something like tailshaft rotation (not too sure if there is anything electronic attached to tailshaft). I can stop the car and get a long continuous beeeeeep or move forward a couple of inches and it goes away completely, in between beeps (if that all makes sense!?!).

I still haven't found what's causing it yet, but I'm guessing it is something like the sensor for the speedo as well. Mine only happens on one frequency 7999 kHz, which is why I haven't sorted it yet.

Interested to hear more about yours and any fix that may be suggested here....C'mon Footy, I know you're onto it...!

Cheers,


Mark