TV interference from model railways

Came across this on the DigitalSpy DTT forum.

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Someone out there is possibly causing TV interference, and it got me thinking just how model railway layouts can be suppressed to prevent it. After all this guy is going to get a neighbour knocking on his door soon! What can be done?

I ask because I am thinking of flooring over my loft and putting a layout up there, and I'm dreading the thought of causing my neighbours upset.

Reply to
Dickie Mint
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I'm trying to think of a nice way of saying "load of bollocks", but I can't.

You listen to all the hoo-ha about the two rails being a giant dipole antenna and causing interference with passing spacecraft (now we know why Beagle2 lost itself) etc etc etc. If someone tries that on you, immediately roll on the floor in front of them laughing fit to bust. Call their bluff. Demand they prove it.

A friend of mine was an electronics engineer on our local TV station, a model railroader and a radio ham as well. He received 2 complaints from neighbours, in both cases their aerials were either wired incorrectly or not even connected. He billed them for the services of another engineer who he had investigate it on his behalf. The bill was correctly calculated, and came to several hundred dollars (Aust). He assured me (with his televison engineers hat on) that it would require a very, very, very (etc etc) sensitive receiver to pick up any signal generated by a model railway. And we're talking quite a few orders of magnitude for the receiver sensitivity.

So don't worry about it, fix up the loft then go play trains!

Steve Newcastle NSW Aust

Reply to
Steve Magee

Yes, I have this problem myself at the moment but as it is a coffee table fiddle yard and the DTT receiver is in the same room, either one is on or the other. There isn't a problem with ordinary TV. It would be distress for the neighbour if I was continuously running in the loft. It would be interesting to know if certain controllers or motors are better or if using 12volts dc from a car battery is better than the mains. Up to now I have had no need to use any suppressors. Mike.

Reply to
Mike Laine

"Dickie Mint" wrote

Model railway stuff has to be suppressed by law, which is why you'll find little suppressors or capacitors inside of modern model trains.

However dirty track or train wheels can cause arcing, which in itself can cause TV interference. Obviously clean track and wheels are less of a problem.


Reply to
John Turner

As I recall, there is a Curing TV Interference booklet in the peco "shows you how series", somtimes given away with Railway Modeller.

I think they cost about 50p........


Reply to
Craig Douglas

Thanks Guys.

Guess there is a problem possible, which someone in Swaffham is causing! Though from the string of postings there it looks more like the village is straining to get any sort of TV reception.

Being in the loft and upstream of local TV aerials obviously makes it worse. I think the 1,000pF across the track at intervals looks the best way to prevent it.

Now what I can't get my head around is why arcing at 16V (max?) can cause it compared to the normal causes of TV interference such as badly surpressed (old?) car ignition running at kVs.

Or, in this case in Swaffham, it's made worse because the TV aerials are high gain and head amps are also being used.

I'd also be interested to know if it is a problem because the guy has maybe removed the loco suppression as is generally suggested for use with DCC. A recent thread on the DCC UK Yahoo group is suggesting this advice is now wrong, because of interference likely to be caused.

I guess no-one out there in this newsgroup has had any complaints?

Here I'm lucky in that it'll only be the new estate currently being built behind my house that might suffer from my loft installation. And we didn't want it anyway ;-)


Reply to
Dickie Mint

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