Power bar noise filter???
 

On Tue, 8 May 2012 20:05:18 -0400, " Tuuk"
wrote:

Anyone have any cheap comments regarding any power bar or surge protector
that have the best RFI EMI noice filtering?

A power bar isn't going to help much:
http://www.powerbarstore.com

As others have suggested, find the source of the noise, and then think
about solutions. In my house, it's the multitude of wall warts and
switching power supplies that generates the bulk of the noise. These
switchers turn off when not charging or powering anything. So, no
noise when they're plugged in, but not being used. Consider using
clamp-on split ferrite filters if you suspect that the noise is being
conducted down the power line.

Light reading:
http://audiosystemsgroup.com/SAC0305Ferrites.pdf
Although the article is on audio noise suppression, it applies equally
well to RF noise suppression.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Power bar noise filter???
 

Thanks for the great advice, I never thought about unhooking the coax to
eliminate that but I know there is also noise coming from the plazma tv,
when it is on, I hear the static, and it immediately stops the static when
the TV is shut off. Now I have read that the screen can transmit through air
the interferrence. I will try the coax unhook today to see isoloate more.
That just makes so much sense. Thanks again and I will try this today.




"Jeff Liebermann" wrote in message
...
On Tue, 8 May 2012 20:05:18 -0400, " Tuuk"
wrote:

Anyone have any cheap comments regarding any power bar or surge protector
that have the best RFI EMI noice filtering?

A power bar isn't going to help much:
http://www.powerbarstore.com

As others have suggested, find the source of the noise, and then think
about solutions. In my house, it's the multitude of wall warts and
switching power supplies that generates the bulk of the noise. These
switchers turn off when not charging or powering anything. So, no
noise when they're plugged in, but not being used. Consider using
clamp-on split ferrite filters if you suspect that the noise is being
conducted down the power line.

Light reading:
http://audiosystemsgroup.com/SAC0305Ferrites.pdf
Although the article is on audio noise suppression, it applies equally
well to RF noise suppression.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Power bar noise filter???
 

" Tuuk" wrote in message
...
Sorry for the delay, work kicked me for a while.

I finally got back to checking and the noise is louder and when unhooking
the tuner (which is attached to the dipole) the noice immediately goes
away. Yesterday was about S9 or S10 of constant noice coming over all the
bands on the HF.

Is there any good Intermod filter for older style solid state rigs? There
must be a cell phone tower or plazma tvs all over my neighborhood. Only
way if that is the case to eliminate this is a intermodulation filter of
some type on my end.

Any good comments I am appreciative, cheap comments welcome as well.

Some things:

CHARACTERIZATION: See if the noise is truly on all the bands. Check every
band for which you have a suitable antenna. Tell us what bands are bad and
how bad. Is the problem the same at 2:00 AM as at 8:00 PM? Do you have
access to a spectrum analyzer?

LOCALIZATION: Get yourself a lot of coaxial cable, perhaps 100 feet and
relocate a portable antenna to places around outside your shack while
another ham calls out the S-meter reading every time you stop someplace and
ask for it. You don't have to have a particularly good match so I'd suggest
you DON'T need ground radials -- just a hamstick on the end of the cable.
Don't hold onto it while your buddy takes the reading; hold it upright with
a plastic or wooden stick a few feet long. Consider buying or borrowing a
portable radio that covers the frequencies affected.

ISOLATION: If you can localize the source, begin powering down. You may be
able to switch off breakers, pending other persons in the house having their
TV go off, or the kitchen go dark at dinnertime, etc. Run your rig off a
battery so you can power down your entire shack. The source could be in a
neighbor's house.

WILD GUESS: Does the tuner have any active circuitry in it? It would be a
real b*tch if the noise were being generated inside the tuner. When you
mentioned "unhooking the tuner," you didn't say which side you were
unhooking.

SNEAK FACTOR (1): A battery-backed-up device, like a smoke detector, CO
detector or burglar alarm could be the problem, but I doubt it.

SNEAK FACTOR (2): If you have more than one problem, you may not know
about Number 2 until after you fix Number 1.

Good luck. I worked interference problems for the Navy and sometimes you
need luck to back up your skill.

"Sal"
(KD6VKW)

Power bar noise filter???
 

On 6/5/2012 10:37 AM, Jeff Liebermann wrote:
On Tue, 5 Jun 2012 09:00:11 -0400, "
wrote:

I finally got back to checking and the noise is louder and when unhooking
the tuner (which is attached to the dipole) the noice immediately goes away.

Does "unhooking the tuner" mean that you've unplugged the antenna lead
from the plasma TV, or that you turned off the plasma TV? If the RFI
is really coming from the antenna connection of the TV, a simple 54MHz
high pass filter should be sufficient to reduce the RF emissions at HF
frequencies to tolerable levels. However, I think turning off the TV
would be better.

Yesterday was about S9 or S10 of constant noice coming over all the bands on
the HF.

I was playing with a Heathkit GC-1000 WWV clock a few nights ago.
Reception was horrible and there seemed to be a rather high noise
level. I turned off everything I could think might be the culprit and
the noise was still there. I gave up for the evening. When I turned
off the room lights, the noise went away. One LED lamp turned out to
be the culprit:
http://www.homedepot.com/webapp/wcs/stores/servlet/ProductDisplay?productId=203088292
I have 3 of these running, but only one of them generates RFI.


So far the best light (warm white), best efficiency and relatively low
noise seems to be from Philips LED bulbs. The ones that have the orange
top are the best. Nothing else comes close. In Minnesota I think there
is a deal going on with Home Depot and the power company because the 60W
Philips bulbs that are normally $40 online everywhere have been $15 at
Home Depot (here) for months.

They are much better than any other LED Edison style bulb I have
purchased, and I've bought quite a few trying to figure out what's good.

The best price/performance is at the 60W level where the $15 bulb
produces 810 lumens for 12W with color rendering at something like 80.
The better version of the bulb does 1100 lumens (or so, can't remember
the number exactly) for only 10W and has about a 99 color rendering
rating. And is $50, only available online. I'd love having that one,
but the math doesn't work out even if I have it for 30 years. I'll wait
for the price to go down.

tom
K0TAR
tom
K0TAR
tom
K0TAR

Power bar noise filter???
 

On 6/5/2012 9:48 PM, tom wrote:
snip


tom
K0TAR
tom
K0TAR
tom
K0TAR

I wonder how I managed to do that.

tom
K0TAR

Power bar noise filter???
 

On Tue, 05 Jun 2012 08:37:59 -0700, Jeff Liebermann
wrote:

You can't "eliminate" EMI/RFI on your operating frequency with any
type of filter. You have to eliminate it at the source.

I lied. If the noise source is coherent, you can get rid of the trash
with a noise canceller:

http://www.timewave.com/support/ANC-4/anc4.html
http://www.youtube.com/watch?v=AzgmH6Zsohg

http://www.mfjenterprises.com/Product.php?productid=MFJ-1026
http://www.youtube.com/watch?v=nPE5vp_3b4A

--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
# http://802.11junk.com
# http://www.LearnByDestroying.com AE6KS

Power bar noise filter???
 

On Tue, 05 Jun 2012 21:48:33 -0500, tom wrote:

In Minnesota I think there
is a deal going on with Home Depot and the power company because the 60W
Philips bulbs that are normally $40 online everywhere have been $15 at
Home Depot (here) for months.

They're about $40 at Home Despot. I was there yesterday to check. I
would probably have bought them except that the cheapo 8 watt Ecosmart
LED lights were on sale for $10/ea. I don't know if you caught my
comment, but I have 3 of them (now 4) but only one generates RFI. I
was going to exchange it for another, but forgot to bring it to the
store. Maybe next time.

The best price/performance is at the 60W level where the $15 bulb
produces 810 lumens for 12W with color rendering at something like 80.
The better version of the bulb does 1100 lumens (or so, can't remember
the number exactly) for only 10W and has about a 99 color rendering
rating. And is $50, only available online. I'd love having that one,
but the math doesn't work out even if I have it for 30 years. I'll wait
for the price to go down.

By comparison, the 8 watt EcoSmart 40w bulb produces and insipid 430
lumens and a 3000K color temperature. Like all the blue+yellow=white
bulbs, they tend to favor the yellow. My eyes can be easily fooled,
but my camera and spectroscope shows the obvious:
http://802.11junk.com/jeffl/crud/EcoSmart%209%20Watt%20LED.jpg
Argh... I can't find the spectra photo. These look like fun:
http://www.scientificsonline.com/diffraction-grating-glasses.html

tom
K0TAR
tom
K0TAR
tom
K0TAR

Pleas turn your echo suppressor back on.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Power bar noise filter???
 

On 6/6/2012 10:07 AM, Jeff Liebermann wrote:

By comparison, the 8 watt EcoSmart 40w bulb produces and insipid 430
lumens and a 3000K color temperature. Like all the blue+yellow=white
bulbs, they tend to favor the yellow. My eyes can be easily fooled,

Yes, they are horrid, but I'd say they favor blue. Regardless, they can
inhale vacuum.

but my camera and spectroscope shows the obvious:
http://802.11junk.com/jeffl/crud/EcoSmart%209%20Watt%20LED.jpg
Argh... I can't find the spectra photo. These look like fun:
http://www.scientificsonline.com/diffraction-grating-glasses.html

I need that. Ordered 12, they're cheap. I'll give the extras to friends.

tom
K0TAR

Power bar noise filter???
 

Thanks guys, lots of good tips.

73s





"Jeff Liebermann" wrote in message
...
On Tue, 05 Jun 2012 08:37:59 -0700, Jeff Liebermann
wrote:

You can't "eliminate" EMI/RFI on your operating frequency with any
type of filter. You have to eliminate it at the source.

I lied. If the noise source is coherent, you can get rid of the trash
with a noise canceller:

http://www.timewave.com/support/ANC-4/anc4.html
http://www.youtube.com/watch?v=AzgmH6Zsohg

http://www.mfjenterprises.com/Product.php?productid=MFJ-1026
http://www.youtube.com/watch?v=nPE5vp_3b4A

--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
# http://802.11junk.com
# http://www.LearnByDestroying.com AE6KS

Power bar noise filter???
 

On Thu, 07 Jun 2012 20:28:21 -0500, tom wrote:

On 6/6/2012 10:07 AM, Jeff Liebermann wrote:

By comparison, the 8 watt EcoSmart 40w bulb produces and insipid 430
lumens and a 3000K color temperature. Like all the blue+yellow=white
bulbs, they tend to favor the yellow. My eyes can be easily fooled,

Yes, they are horrid, but I'd say they favor blue. Regardless, they can
inhale vacuum.

Your eyes are suppose to more sensitive in the yellow area than blue.
Getting the ratio between the blue LED and the yellow phosphor right
is a major headache. Among my 4ea Ecosmart bulbs, I can't really see
much variation. However, my camera certainly sees differences. One
is rather blueish, while the others are varying shades of yellowish.
I'll try to take a phone of all 4 of them at the same time. That's a
problem right now because they're installed all over the house.

Also, another advantage of LED light bulbs is that they can be dropped
without breaking.

Argh... I can't find the spectra photo. These look like fun:
http://www.scientificsonline.com/diffraction-grating-glasses.html

I need that. Ordered 12, they're cheap. I'll give the extras to friends.

It's made for "raves" but works equally well for a fast spectrographic
analysis. There are other diffraction grating type spectrometers
available, but it's difficult to beat the price.


--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
# http://802.11junk.com
# http://www.LearnByDestroying.com AE6KS