On 21/11/2015 14:34, Dave Plowman (News) wrote:
In article ,
Brian-Gaff wrote:
With the proliferisation of mobile devices running on the mobile phone
network its getting increasingly a annoying to listen to things on a
good old fashioned or even new fangled radio, without the noise
occurring at some point. Even from next door one can get it getting into
the audio chain. Anyone know if there is an easy way to stop it. In the
old days a few capacitors got rid of Radio China or Vatican City, but
due to the high frequencies of the phones and the spiky nature of the
handshaking noise, this seems not to work much. What is the mechanism.
they cannot be tuned to the r frequencies, so is it just straight diode
type detection due to the huge signal level?

Low level circuits like turntables, microphone inputs etc, seem to be
the worst, but I've also proved my Denon is picking it up from its
speaker cables.

You seem to be very unlucky or live in an odd area or have odd equipment
if you're picking up interference on a pickup or mic?

My laptop reports some 20 Wi-Fi signals at usable level round here, but no
problems on the Hi-Fi here. Or with mobile phones which I'd guess are as
common as the above.

Obviously, roaming the radio waves for distant and obscure stuff might be
a different matter.


FWIW, my iPhone's 'polling' (not sure how, what or why) can be heard on
my hifi, FM radios, and work's PA systems in lecture halls. It's a sort
of chirping, and lasts about 10s.

--
Cheers, Rob

In article ,
RJH wrote:
You seem to be very unlucky or live in an odd area or have odd
equipment if you're picking up interference on a pickup or mic?

My laptop reports some 20 Wi-Fi signals at usable level round here,
but no problems on the Hi-Fi here. Or with mobile phones which I'd
guess are as common as the above.

Obviously, roaming the radio waves for distant and obscure stuff might
be a different matter.


FWIW, my iPhone's 'polling' (not sure how, what or why) can be heard on
my hifi, FM radios, and work's PA systems in lecture halls. It's a sort
of chirping, and lasts about 10s.

Yes - that does happen, but moving the phone away a few feet should sort
it.

It used to happen frequently on live radio etc broadcasts despite those in
the studio being told to turn off any phones. Rather than go to silent.
It's far less common these days, so something has changed.

--
*Reality is a crutch for people who can't handle drugs.

Dave Plowman London SW
To e-mail, change noise into sound.

On 22/11/2015 10:41, Dave Plowman (News) wrote:
In article ,
RJH wrote:
You seem to be very unlucky or live in an odd area or have odd
equipment if you're picking up interference on a pickup or mic?

My laptop reports some 20 Wi-Fi signals at usable level round here,
but no problems on the Hi-Fi here. Or with mobile phones which I'd
guess are as common as the above.

Obviously, roaming the radio waves for distant and obscure stuff might
be a different matter.


FWIW, my iPhone's 'polling' (not sure how, what or why) can be heard on
my hifi, FM radios, and work's PA systems in lecture halls. It's a sort
of chirping, and lasts about 10s.

Yes - that does happen, but moving the phone away a few feet should sort
it.

It used to happen frequently on live radio etc broadcasts despite those in
the studio being told to turn off any phones. Rather than go to silent.
It's far less common these days, so something has changed.


It was worse with analogue phones IIRC. Used to get it a lot on RTB
feeds on OBs

--
Graeme Wall
This account not read, substitute trains for rail.

In article ,
Graeme Wall wrote:
Yes - that does happen, but moving the phone away a few feet should
sort it.

It used to happen frequently on live radio etc broadcasts despite
those in the studio being told to turn off any phones. Rather than go
to silent. It's far less common these days, so something has changed.


It was worse with analogue phones IIRC. Used to get it a lot on RTB
feeds on OBs

You've got me confused now. ;-) My first phone - 1992 - was a Technophone
analogue, and that didn't induce the chirping noise. It was replaced (when
the service stopped) with a Nokia, and that did. I still have it, and it
still works, so I assume was on the current digital system?

I do remember it causing a problem on a Calrec analogue sound desk while
clipped to my waistband. Moving it a few feet away sorted it.

--
*Seen it all, done it all, can't remember most of it*

Dave Plowman London SW
To e-mail, change noise into sound.

In article , RJH wrote:

FWIW, my iPhone's 'polling' (not sure how, what or why) can be heard on
my hifi, FM radios, and work's PA systems in lecture halls. It's a sort
of chirping, and lasts about 10s.

We don't get any problems from phones, etc, even when using one in the same
room. This is despite a lot of the kit I use being pretty old - i.e. like
me!

I always fitted an RC at the input to amps and a full Zobel (series
inductor/resistor as well as shunt cap/resistor) to help block crap getting
in. I also put caps across all four mains bridge diodes and across the
mains input.

On 22 Nov in uk.rec.audio, Woody wrote:
In many cases putting a loop or two the speaker cable through a ferrite
ring will kill the interference dead, but have you tried buying ferrite
rings these days? At one time they were easily obtained and in many
varieties but now - lets us say rocking horse manure comes to mind.

FWIW I buy rings from CPC. I'd echo that they often deal with garbage
picked up from the speaker leads. As you only have to wind the lead though
them they are an easy fix for people to try.

The Armstrong 626 I had refurbished recently was an early version. These
were prone to clicks, etc. The first impression might be that they were
getting in via the mains. They also have a wooden lid and plastic base, so
are exposed to external fields. (Unless you line them with ali foil or
mu-metal!) But experiment showed me that it was via speaker leads. Solved
with ferrite clip-on blocks/rings.

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
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