AM Radio =-interference- Is there a plug-in or easy filter

[michael....@gmail.com]

I have a 1970's GE clock transistor radio. On AM stations, (1060) there is a lot of buzz/hum. However when I turn ON various CFL light fixtures around the house, the hum disappears. Is there a filter commercially available to put on the AC line? Or can I make one? I've tried reversing the plug (that used to work years ago). Any suggestions? TIA- vze2m645 at verayzon dot nat, you know what I mean.

[Phil Allison]

<michael....@gmail.com>

> I have a 1970's GE clock transistor radio.

** Still working ??

> On AM stations, (1060) there is a lot of buzz/hum.

** The usual cause is AC supply frequency modulation of AM radio signals
arriving on power wiring in the premises.

> However when I turn ON various CFL light fixtures around the house, the
> hum disappears.

** CFLs nearly all have a 100nF or 220nF capacitor that connects directly
across the incoming AC wires. These reduce any AM band signals to a much
lower level and so avoid the aforementioned supply frequency modulation.

> Is there a filter commercially available to put on the AC line?

** Doubt it.

> Or can I make one?

** A 1uF, 275VAC cap is all you need.

Wired into the back of a regular AC plug.



... Phil

[michaelm]

Thnks Phil. does that cap go in series with one lead of an ACPlug, or across thepower line.

[Phil Allison]

"michaelm"


** Fix you fucking settings !!!!!!!!!!!!!!

And learn how to read.



.... Phil

[Nightcrawler®]

"Phil Allison" <phi...@tpg.com.au> wrote in message news:berstk...@mid.individual.net...

Learn how to spell !!!!!!!!!!!!!

And, get OE Fix, too. :-)

In all fairness to Phil, after he had his grumpy juice for
breakfast, he did state to put the capacitor across the
incoming AC line i.e. parallel. With a molded plug you would
have to be quite clever, but you may buy a replacement, two
piece plug and wire the capacitor into the circuit, minding
to heat shrink the capacitor leads.

[jurb...@gmail.com]

Forget it, none of this shit is going to work. The simple fact is that there is so much shit putting out interference in that band that nothing is going to eliminate it.

You can't shield it from the power line because it is conming in from THE ANTENNA ! You would have to filter the frequencies you want to recieve.

It's different when you are out in a truck on the highway in bumfuct Kansas somewhere. Then AM can work.

Think about it, AM is about one megacycle. Yup, not even Hertz. It's that old. I hate to say it, but AM is just about dead. I used to like CKLW. In fact CKLW used to be one of the most popular stations in the whole country. The problem now is that even your fucking clothes apparently enamate RF in that low band.

Shortwave is just as bad.

There is a damn good reason that the technology has tended toward higher frequencies. In fact, like OVER ten years ago I advocated the elimnination of the VHF band for television. On channel 3 (US, about 60 Mhz) if a car was driving down the road and had a bad spark plug wire it would cause interference.

Fuck that.

[Nightcrawler®]

<jurb...@gmail.com> wrote in message news:3d87ceed-3334-4bf2...@googlegroups.com...

You seem to be retarded. The OP already stated that the noise was eliminated by
turning on a CFL.

If the OP could kill the power to the receptacle, solder some extension wire to the
cap leads, and then wire the cap across the back of the receptacle. Minding to heat
shrink the leads of the cap, and using a larger heat shrink, encapsulate the cap and
all of the smaller heat shrink. Make the extension leads 6" long.

[mike]

Wouldn't it be easier to put the cap inside the radio?

Be careful with your choice of cap.
I put a quality 600V cap across 220VAC inside the dryer to
bridge the phases to make X10 work. Worked great for two
years before it exploded spectacularly. Good thing it was
inside a metal box.

[Phil Allison]

"Nightcrawler�"

> "Phil Allison" <

>>
>> "michaelm"
>>
>>
>> ** Fix you fucking settings !!!!!!!!!!!!!!
>>
>> And learn how to read.
>>
>>
>

> Learn how to spell


** Get a life - you fucking IDIOT !!!!!!

[Phil Allison]

<jurb...@gmail.com

Forget it, none of this shit is going to work.

** So you do not understand the issue.

AM radio often signals "piggy back" into premises on the AC power and are
then re- radiated with supply frequency related modulation - mainly 100
or 120Hz and harmonics.

They also arrive by penetrating walls and windows without such modulation.

The loopstick antenna in the OP's radio picks up either or both.

It may even have a small cap connecting to the incoming AC to enhance the
effect.

Get it now?


.... Phil

[Phil Allison]

"mike"

> Wouldn't it be easier to put the cap inside the radio?

** Worth a try - if it will fit.

> Be careful with your choice of cap.
> I put a quality 600V cap across 220VAC inside the dryer to
> bridge the phases to make X10 work. Worked great for two
> years before it exploded spectacularly.

** My post specified a 275VAC cap ( aka class X1 or X2 suppression caps) .

These are specially would to avoid internal corona that destroys ordinary
film caps wired across the AC line.

If you cannot get any, try two 600V film caps in series - that ought to
work OK too.



.... Phil

[jurb...@gmail.com]

>

What the fuck.

>"You seem to be retarded. "

Yeah well my shit that I design and build works.

What say you ?

[jurb...@gmail.com]

Zanother thing. You think you can prevent a reciever from recieving that which to it is tuned ? All that fucking noise is right there in the passband.

who the fuck here is so damn good that they cn selectively reject the noise wehn it is in the same bandw, and frequency, as the desired signsl ?

I don't know what kind of schoopkls they got down under, b ut in between buxting your heads and shit, they must be pretty fucking good.

Look up Lewin A.R.W. Edwards if you want to see a REAL resume'. In fact he toned his resume' down a bit. Maybe it wss embarrassing too many people.

Know what I say when this shit happens ?


Fukum.

[jurb...@gmail.com]

God damn am I toast right now.

[Allodoxaphobia]

On Mon, 18 Nov 2013 11:51:46 +1100, Phil Allison wrote:
>
> They also arrive by penetrating walls and windows without such modulation.

Not if the window glass is "Low-E" and the walls are stucco.
Such dwellings are almost a Faraday cage.
I live in one. Most of my AM reception is of RF trash
generated _inside_ the house.

[Geoffrey S. Mendelson]

Allodoxaphobia wrote:
> Not if the window glass is "Low-E" and the walls are stucco.
> Such dwellings are almost a Faraday cage.
> I live in one. Most of my AM reception is of RF trash
> generated _inside_ the house.

I found this idea on a web page from a company that makes small high gain
antennas for shortwave listening.

Take a portable radio and find the end of the "noise cloud" around your
home an put an antenna there. Of course if you are in a tight urban
area, or an apartment, you may never find it. :-(

Geoff.


--
Geoffrey S. Mendelson, N3OWJ/4X1GM/KBUH7245/KBUW5379

[William Sommerwerck]

wrote in message news:3664a0c1-9b7a-4686...@googlegroups.com...

> Another thing. You think you can prevent a reciever from receiving
> that to which it is tuned? All that fucking noise is right there in the
> passband.

> Who the fuck here is so damn good that they can selectively reject

> the noise wehn it is in the same bandw, and frequency, as the desired

> signal?

If RFI is coming down the power line, it can be choked before it reaches the
receiver.

I've done this with FM tuners. It reduces multipath that gets in through the
power line and the antenna cable's shield.

[amdx]

On 11/17/2013 5:36 AM, michael....@gmail.com wrote:
> I have a 1970's GE clock transistor radio. On AM stations, (1060) there is a lot of buzz/hum.

However when I turn ON various CFL light fixtures around the house, the
hum disappears.

Leave the light on!
Put a shade on it?
Paint it black?

[Michael Black]

On Mon, 18 Nov 2013, Geoffrey S. Mendelson wrote:

> Allodoxaphobia wrote:
>> Not if the window glass is "Low-E" and the walls are stucco.
>> Such dwellings are almost a Faraday cage.
>> I live in one. Most of my AM reception is of RF trash
>> generated _inside_ the house.
>
> I found this idea on a web page from a company that makes small high gain
> antennas for shortwave listening.
>
> Take a portable radio and find the end of the "noise cloud" around your
> home an put an antenna there. Of course if you are in a tight urban
> area, or an apartment, you may never find it. :-(
>

I remember forty years ago I could just stick a few feet of wire on the
SP-600 and reception was fine. Now, there is so much noise from all the
electronic junk that didn't exist back then, that you really need the
antenna outside, or at the very least, next to the window. The signals
suddenly leap out, but it's a combination of stronger signals from
outside, and weaker signals from inside.

Michael

[jurb...@gmail.com]

>"Now, there is so much noise from all the

electronic junk that didn't exist back then..."

That's what I'm talking about. These days if it ain't Ghz there is all kind of noise all over the place. Sure there is some on the power lines etc., but it is also in the air.

Just for a test, if anyone is so inclined, just take a scope probe and connect it to a big piece of metal. You are going to see more shit there than... well, I lack a proper metaphor at this moment. Sorry. But there is alot. Sometimes I'm surprised anything works.

[amdx]

Back many years ago, I had a shop scope that picked up a 1430 khz
modulated signal clean as could be.
Mikek

[Phil Allison]

"Allodoxaphobia"

Phil Allison wrote:
>>
>> They also arrive by penetrating walls and windows without such
>> modulation.
>
> Not if the window glass is "Low-E" and the walls are stucco.
> Such dwellings are almost a Faraday cage.
> I live in one. Most of my AM reception is of RF trash
> generated _inside_ the house.
>

** Folk living in mobile or re-locatable homes with * metal * walls have a
bit of a problem with AM radio too...



.... Phil

[dave]

On 11/18/2013 02:59 AM, jurb...@gmail.com wrote:
> Zanother thing. You think you can prevent a reciever from recieving
> that which to it is tuned ? All that fucking noise is right there in
> the passband.
>

I have a device called the MFJ-1026 that does that. It requires a
safecracker's touch and 2 antennas.

[Paul Drahn]

I have such a triple-wide home. Aluminum siding all around. Fortunately,
the roof is not metal, so the little RF'ies can get in there! My pole
shop/garage is worse. Has 4 metal walls, plus metal roof.

Paul

[Peter Jason]

Does this apply to TV interference too? My TV
works only on some channels and the rest show "no
signal" or severe pixellation. Also, the trouble
is intermittent. What can I do? Is there some
sort of filter to fix it?

[Look165]

I thought AM was released on the prehistoric era !

Anyway, perturbations might come from AC mains, solar eruption,
neighborhood electric signals, HV lines, AC generator...

To be sure, try to move this AM receiver somewhere else (a friend ?)

Don't forget to check the antenna and/or the orientation of the receiver.

Sometimes, a single 1m wire hanging downward is a good antenna.

Another experiment is to move the receiver near the TV cable
disconnected fromthe TV set.

Since it is an old apparatus, it might be a misalignment of the
receiving part and/or IF section.

A simple cause can also be the loudspeaker (visual check is generally
enough).

If you are lucky, there can be the electric diagram inside.

Peter Jason a écrit :

[John-Del]

You don't need a "filter", you need to improve your signal to noise ratio. You need a larger antenna, raise the elevation of the antenna, amplification, or moving nearer to the TV transmitter..

[Look165]

No, no relation between AM and TV

For TV check the antenna.

As I said, try it somewhere else.

For the AM receiver, it must be a failure of the AM set (Receiver and
IF section) ; with time (48 years) some inductanes change their value
and condensators too.

John-Del a écrit :

[Terry Schwartz]

Once again, replying to a 5+ year old post.

[Dave Platt]

In article <6kepvd5m3sf4ijcd8...@4ax.com>,

Peter Jason <mmmm> wrote:

>Does this apply to TV interference too? My TV
>works only on some channels and the rest show "no
>signal" or severe pixellation. Also, the trouble
>is intermittent. What can I do? Is there some
>sort of filter to fix it?

The first question I would ask is, "What's your antenna setup?"

For TV, and for FM radio, the most important aspect to getting good
signal quality is having a good antenna arrangement - a proper antenna
mounted where it can "see" the transmitters with a minimum of
interfering solid matter between the two.

Indoor antennas - "rabbit ears", floppy dipoles, and small wall-mount
panel antennas - are usually suitable only for "strong signal" areas
fairly close to the transmitters. Modern buildings are often quite
effective shields against RF transmission - they contain materials
which either absorb or reflect RF - steel beams, wire mesh in stucco
walls, metallized plastic insulation and vapor barriers, and so
forth. Signals from distant stations don't stand a chance... they're
weakened, and also degraded by multipath (multiple RF paths of
different lengths, caused by signal reflections, which result in
frequency-selective signal reinforcement and cancellation).

The results of all of this are bad signals. Analog TV suffers from
noise and "ghosts". FM suffers from noise and distortion. Digital TV
suffers from pixellation, freezing, and "no signal found" problems.

These problems can all be made worse by local interference, radiated
or conducted. They're also made worse by short-term multipath -
e.g. signal reflections from airplanes flying within the
line-of-sight, or even trucks driving by on the road outside. On FM
you can hear a "picket fencing" effect when this happens, on analog TV
you see moving "ghosts", and on digital TV you see pixellation and
freezing. Digital TV receivers do have the ability to detect and
cancel out some multipath reflections, but dealing with rapidly
changing reflections is a "hard problem" for them and they often don't
adapt fast enough.

Filters at the receiving end (TV, FM radio) won't help, except in the
case where the TV is picking up _conducted_ RF interference through
the power line. Can't hurt to try, but don't expect miracles.

Filters at the sources of interference (noisy motors, PC power
supplies, LED lights, light dimmers) may help somewhat. However, even
if you completely filter all local noise sources, there can still be
plenty of noise from outside the house/apartment - neighbors'
equipment, etc.

The real "fix" is to improve the quality of the incoming RF
signal... you want a strong signal with minimal multipath. This often
requires an outdoor antenna - one mounted up "in the clear" (e.g. on a
roof mast). If possible, install a directional antenna which is aimed
in the direction of the desired transmitter - this both boosts the
amount of "good" signal (thanks to the antenna's gain) and also
reduces the amount of "bad" signal (multipath reflections coming in
from other directions, and random interference from sources in the
area). If necessary, install a remote-controlled antenna rotator, or
an electronically-rotatable antenna (if your TV has the ability to
control one of these - most do not, I believe).

If you're getting your over-the-air TV signal via a cable-TV feed, and
the quality is still poor, then check your coax connections, and/or
complain to the cable company.