Topband: RFI - and lots of it

[Keith Jillings (G3OIT)]

On 30/10/2015 19:22, Guy Olinger K2AV wrote:

 > Electrical advice via a 160 meter ham radio reflector from individuals
 > scattered all over the globe? Even individuals qualified in their
 > particular location. What could possibly go wrong  :>)

Exactly so!

Where I am, ALL the copper pipes in the cupboard where the water main 
enters the house, and via which the hot and cold water and heating pipes 
head into the boiler and off in their various directions, are bonded 
together.

It's not thin stuff - it's thick multistrand cable, clamped to each pipe 
with a large red and silver metal label saying "Safety Electrical Earth 
- Do Not Remove".   That's mandatory in the UK and (I suspect) in the 
rest of the EU.

The incoming water main is in the regulation blue plastic pipe (blue = 
potable), but there is a mains earth which I think is a cluster of 
copper rods hammered into the ground.   The house is 500 years old and 
the earth connection is under the cupboard floor, so I don't mess with it.
We don't get a lot of RFI noise coming in that way.

There is similar bonding between the hot and cold pipes at the bathroom 
sink, the bath, the kitchen sink, the utility room sink, and so on.   My 
ohmmeter reads zero between any pair of copper pipes I can get to.

There are, of course, no power sockets in the bathroom or toilet within 
reach of the sink.  That's been banned here for a very long time:  fused 
transformers are supplied for shavers.   Light switches are the "drop 
cord" type, although conventional switches are allowed if they meet the 
latest safety regulations or are more than some distance from the sink.


73

Keith
G3OIT