Ham radio Interference
 

In message , Graham.
writes


"Bill Wright" wrote in message
...

"Terry Casey" wrote in message
...
Dave H wrote:
"where's that bleedin' 'usband of yours? I know it's 'im - 'im and 'is
bloody 'am radio. Our telly's bloody awful tonight - we can't watch a
bleedin' thing! I wannit off, and I wannit off right now!!"

Tom's wife would then patiently explain that he was in Birmingham or
Bristol or somewhere equally distant and wouldn't be back to the
following day...

When a radio amateur moves house or intends to start a station, he should
install a big aerial at least six months before he buys and radio
equipment. Then, when the complaints come in, he can show the complainer
the end of the cable, with no equipment attached.

Very true, I got more than one knock on my door before I was
licensed when all I had connected to my aerial was an R107
WWII ships receiver.

Mind you, the home-built valve super-regenerative sets I built
while I was still at school *did* have the potential to cause
interference.

Putting up aerials - but not using them for some time - is indeed a
useful bit of advice often given to radio amateurs. There are two
advantages:

1. As already stated, if any interference problems arise, it should be
possible to convince the neighbours that amateur transmissions are not
responsible.

2. The neighbours don't immediately associate the onset of any
interference problems with the erection of the aerials, and then
complain to the local council that they are an eyesore. [They might be,
of course, but interference - or the threat of it - cannot legally be
used to challenge the granting of planning permission.]

[BTW, I'm sure that the R107 was an army receiver. I have one right
here, 3 feet away from me. I've had it since 1958.]
--
Ian

Ham radio Interference
 

"Ian Jackson" wrote in message
...
In message , Steve Terry
writes
"James R" wrote in message
...
"Dave H" wrote in message
...
snip
It would be in his own interest to solve the interference as OFCOM will
be
on your side on this one.

What an assumption!
It's possible Ofcom officals wouldn't understand cause and effect
as much as you?
But it's their job to do so
Steve Terry

In the good olde days, there was at least one Post Office interference
inspector who seemed to be convinced that all interference was caused by
harmonics - even if the affected equipment was audio-only.
Ian


He obviously had too much faith in the hymn sheet he'd learnt off by heart

Unless they were very low frequency sub harmonics? ;-)

Steve Terry

Ham radio Interference
 

Dave H wrote:
"where's that bleedin' 'usband of yours? I know it's 'im - 'im and 'is
bloody 'am radio. Our telly's bloody awful tonight - we can't watch a
bleedin' thing! I wannit off, and I wannit off right now!!"

Tom's wife would then patiently explain that he was in Birmingham or
Bristol or somewhere equally distant and wouldn't be back to the
following day...

When a radio amateur moves house or intends to start a station, he
should
install a big aerial at least six months before he buys and radio
equipment. Then, when the complaints come in, he can show the complainer
the end of the cable, with no equipment attached.

Very true, I got more than one knock on my door before I was
licensed when all I had connected to my aerial was an R107
WWII ships receiver.

Mind you, the home-built valve super-regenerative sets I built
while I was still at school *did* have the potential to cause
interference.

Putting up aerials - but not using them for some time - is indeed a useful
bit of advice often given to radio amateurs. There are two advantages:

1. As already stated, if any interference problems arise, it should be
possible to convince the neighbours that amateur transmissions are not
responsible.

2. The neighbours don't immediately associate the onset of any
interference problems with the erection of the aerials, and then complain
to the local council that they are an eyesore. [They might be, of course,
but interference - or the threat of it - cannot legally be used to
challenge the granting of planning permission.]

[BTW, I'm sure that the R107 was an army receiver. I have one right here,
3 feet away from me. I've had it since 1958.]

I'm sure you are right, I got mine about 11 years later, it cost
£15 from G3MAXs place in Manchester; I really wanted
an AR88D but they were too expensive.

--
Graham.

%Profound_observation%

Ham radio Interference
 

"Steve Terry" wrote in message
...

"Roderick Stewart" wrote in
message .myzen.co.uk...
In article , Steve Terry wrote:
Ducks float so does wood, therefore ducks are made of wood,
No? Then why do you believe RF interferes with Audio?

RF can interfere with audio, video, servo controls, telemetry, or the
fillings in people's teeth.
Rod.


Nope, audio, video, servo controls, telemetry, or the fillings
in people's teeth. can receive RF when they are not designed to

RF can warm the cockles of your heart.

Bill

Ham radio Interference
 

Bill Wright wrote...

RF can warm the cockles of your heart.

And also makes a handy emergency fag lighter.


--
Ken
Digital switchover advice
http://www.paras.org.uk/01-intro.shtml

My feeble audio links site
http://unsteadyken.sitegoz.com/

Ham radio Interference
 

The message
from "Bill Wright" contains these words:

====snip====

RF can warm the cockles of your heart.

It can certainly warm the cockles, just put some in a microwave oven
and you'll soon see the truth of that statement. ;-)

--
Regards, John.

Please remove the "ohggcyht" before replying.
The address has been munged to reject Spam-bots.

Ham radio Interference
 

A homebrewed (and designed) 50W per channel amplifier was likewise
immune (probably the result of it being a bridged output design and the
speaker leads being a balanced circuit, rather than the more susceptable
unbalanced one typical of the more common single ended design).

FWIW ... most all interference is caused by unwanted demodulation
normally done in a semi conductor junction and usually the base emitter
one of yer average transistor. By pass that with a few pf of capacity
will see off most all RFI problems..a series RF choke sometimes does the
same thing..

Problem is that you have to identify which one and then get inside the
offending item.. Not straightforward..

In the case of TV reception, a simple 'braid breaker' will often
decouple the 'Long Wire' effect of the TV antenna feeder from the
chassis (the usual route for such MF breakthrough problems).

Such a simple braid breaker can be made from a 2 metre 'flylead' wound
onto a 2 or 3 inch diameter form made from plastic or cardboard.
Alternatively, a set of ferrite sleeves or small rings can be slipped
over the co-ax or an in-line filter can be made from a short length of
thin 75 ohm co-ax wound onto a larger ferrite ring (2 or 3 inches
outside diameter with 4 or 5 spaced turns occupying no more than 3
quarters of the ring's circumference) with a male and female belling lee
plug fitted to the cable ends.

This type of remedy is a non-invasive one that can be tried without
risk to warranty or equipment safety. Indeed, the amateur in question
may offer to supply a braid breaker filter FoC by way of good will (it's
a cheap way to maintain a 'Quiet Life' ;-)


A braid breaker is a simple form of high pass filter .. fine if he's
operating on the HF channels but not quite so useful on 144 MHz (2
meters or 70 cms around 430 odd)..

However a TETRA filter might be worth a go for those..


If the OP uses his noggin, he can engage the amateur in an amicable two
way conversation that turns the 'complaint' into a form of flattery (as
in "Hey, that beam antenna of yours must be good, 'cos it's only when
you point it my way that my TV set succumbs to breakthrough; you don't
happen to know how to cure the problem by any chance?" sort of thing.
;-)


He might even join the fraternity .. people collect train numbers don't
they;)...
BTW, the problem might even be down to nearby metalwork with corroded
joints acting as a rectifier, distorting the resulting amateur band
transmission current flow that would otherwise be totally harmless and
produce harmonics extending into the UHF band, directly interfering with
the TV signal.


Another form of semi conductor ;)

More found on radio comms sites...

At the end of the day, you don't want to involve OFCon unless you
really have no further recourse.

If they've got anyone left in the enforcement side;!..


HTH


--
Tony Sayer

Ham radio Interference
 

[snip]
BTW, the problem might even be down to nearby metalwork with corroded
joints acting as a rectifier, distorting the resulting amateur band
transmission current flow that would otherwise be totally harmless and
produce harmonics extending into the UHF band, directly interfering
with
the TV signal.


Another form of semi conductor ;)

More found on radio comms sites...



I've long thought this to be an urban myth. I'm in my 40th year in the
mobile radio business and 31st as a field tech for a large part of which
I covered the whole of the north of England and north Wales and I have
never come across this problem.

Now a woman near Scarborough that could hear the local council depot
(which did not have a Tx on site) on her radio, cassette recorder,
microwave, toaster...........



--
Woody

harrogate three at ntlworld dot com

Ham radio Interference
 

"Woody" wrote in message
...
[snip]
BTW, the problem might even be down to nearby metalwork with corroded
joints acting as a rectifier, distorting the resulting amateur band
transmission current flow that would otherwise be totally harmless and
produce harmonics extending into the UHF band, directly interfering with
the TV signal.


Another form of semi conductor ;)

More found on radio comms sites...



I've long thought this to be an urban myth. I'm in my 40th year in the
mobile radio business and 31st as a field tech for a large part of which I
covered the whole of the north of England and north Wales and I have never
come across this problem.

Now a woman near Scarborough that could hear the local council depot
(which did not have a Tx on site) on her radio, cassette recorder,
microwave, toaster...........

Well the manufactures of NLJDs for the counter-surveillance industry
don't think it's a myth.

Is the Scarborough woman on-going? Don't discount the possibility
that she "hears voices".

--
Graham.

%Profound_observation%

Ham radio Interference
 

In message , Graham.
writes

Is the Scarborough woman on-going? Don't discount the possibility
that she "hears voices".


The voices may not be real, BUT, they do talk a lot of sense.


--
Bill