C. Crane's Twin Ferrite Antenna
 

K7JEB wrote:

On Wed, 30 Nov 2005 13:26:37 GMT, "W. Watson"
wrote:


W. Watson wrote:
I'll continue to experiment, but so far not
so good. Comments?


I would like to relate my experience. As you
did, I carefully selected a new computer case
and power supply from the stock at redacted,
paying careful attention to the FCC logo on the
power supply. After moving the mother board
over and turning it on, it completely wiped
out reception of the local 5kW station on 550 kHz.
Fortunately, I had picked up a couple of surplus
Corcom line filters (Model # 10ESK7)at a local
hamfest three years earlier (it pays to collect
junk). I spliced it into the computer power
cord and it cured the problem completely.

I don't have any experience with the Radio
Shack line filter (Catalog # 15-1111), but it
looks like it might do the job for you.

73, Jim, K7JEB


The RShk ferrite rectangles didn't help. Interesting about the Corcom
filters. I'm going down to a radio shop on Friday, HSC in Sacramento. Maybe
I can find something there.

I just checked Google with "Corcom line filters Model # 10ESK7" and found
some hits. Look like maybe they are $5.00.

Interesting finding about the width of the noise on a msg I just posted a
few minutes ago.

--
Wayne T. Watson (Watson Adventures, Prop., Nevada City, CA)
(121.015 Deg. W, 39.262 Deg. N) GMT-8 hr std. time)
Obz Site: 39° 15' 7" N, 121° 2' 32" W, 2700 feet

Traveling in remote places in the winter. What's the best
tool to carry with you? An axe.
-- Survivorman, Discovery (SCI) Channel

Web Page: home.earthlink.net/~mtnviews

C. Crane's Twin Ferrite Antenna
 

On Thu, 01 Dec 2005 00:20:41 GMT, "W. Watson"
wrote:

I don't have any experience with the Radio
Shack line filter (Catalog # 15-1111), but it
looks like it might do the job for you.

The RShk ferrite rectangles didn't help.
Interesting about the Corcom filters. I'm going
down to a radio shop on Friday, HSC in Sacramento.
Maybe I can find something there.

Take a look at the 15-1111 on www.radioshack.com.
It is NOT a clamp-on ferrite choke, but rather
a filter like the Corcom. I just thought it might
be a bit more accessible. But if you can find a
10-amp Corcom, go for it! (Actually, a 3-amp model
should work). Anyway, your problem is definitely
solvable, and for relatively little $$$.

Jim, K7JEB

C. Crane's Twin Ferrite Antenna
 

Computers and computer components are regulated by the FCC.
They MUST NOT cause interferance to licenced radio services.
(like the radio stations you are trying to tune in.)
Make that clear to the vendor you got the power supply from!

KD5RPO




W. Watson wrote:
Michael Coslo wrote:

W. Watson wrote:

I bought this antenna on a 30 day trial, and just got it about 12
hours ago. So far I'm not at all impressed. I live about 150 miles
from an AM station, at 810, in the SF/SJ Bay Area, which has a
marginal signal, but usually listenable. Putting a new PSU in a PC
about a month ago increased the noise in AM radios 70-100' from the
PC to an almost unacceptable level. I had hoped the antenna would
boost the signal enough to knock down the noise. There are times when
I can get a good signal from the station, but certainly less
frequently than before.



Any rf noise put out by the computer ps is going to be picked up
by your antenna as well as the radio station you are trying to hear.
So a better antenna (if your new one is indeed better) wil just pick
up stronger power supply noise. It's moslty a null situation.

What you need to do is get that power supply fixed or replaced

- 73 de Mike KB3EIA -

I think the only solutions to the PSU problem is to buy a much better
one. As I mention above, that's probably a losing proposition. I doubt
after 6 weeks they would take it back. It might be worth a try though.
Note my comment above to someone a few moments ago that this seems to be
a household circuit dependent problem. Another PC in the same room works
fine until I plug it into the socket that I first noticed the problem.

C. Crane's Twin Ferrite Antenna
 

BKR wrote:
Computers and computer components are regulated by the FCC.
They MUST NOT cause interferance to licenced radio services.
(like the radio stations you are trying to tune in.)
Make that clear to the vendor you got the power supply from!


Interesting thought but impractical. It could be the installation
(e.g., grounding) vs. the supply itself. Event if the PSU itself,
proving it would be a chore.

C. Crane's Twin Ferrite Antenna
 

"Phil Wheeler" bravely wrote to "All" (01 Dec 05 09:53:08)
--- on the heady topic of " C. Crane's Twin Ferrite Antenna"

PW From: Phil Wheeler
PW Xref: core-easynews rec.radio.amateur.antenna:220688

PW BKR wrote:
Computers and computer components are regulated by the FCC.
They MUST NOT cause interferance to licenced radio services.
(like the radio stations you are trying to tune in.)
Make that clear to the vendor you got the power supply from!


PW Interesting thought but impractical. It could be the installation
PW (e.g., grounding) vs. the supply itself. Event if the PSU itself,
PW proving it would be a chore.

Especially since most of the off-shore stuff may have all the right
stickers but be complete fakes of the real thing.

A*s*i*m*o*v

.... We're young, rich, and full of sugar, what do we do?

C. Crane's Twin Ferrite Antenna
 

K7JEB wrote:

On Thu, 01 Dec 2005 00:20:41 GMT, "W. Watson"
wrote:


I don't have any experience with the Radio
Shack line filter (Catalog # 15-1111), but it
looks like it might do the job for you.


The RShk ferrite rectangles didn't help.
Interesting about the Corcom filters. I'm going
down to a radio shop on Friday, HSC in Sacramento.
Maybe I can find something there.


Take a look at the 15-1111 on www.radioshack.com.
It is NOT a clamp-on ferrite choke, but rather
a filter like the Corcom. I just thought it might
be a bit more accessible. But if you can find a
10-amp Corcom, go for it! (Actually, a 3-amp model
should work). Anyway, your problem is definitely
solvable, and for relatively little $$$.

Jim, K7JEB



Good. Thanks. I'll try RS tomorrow. Sometimes they don't have to stock them.
I'll be going by Fry's Electronics tomorrow in Sacramento. They stock one
heck of a lot of electronics stuff. I think I'll call down first or try
there web site for the corcom.

--
Wayne T. Watson (Watson Adventures, Prop., Nevada City, CA)
(121.015 Deg. W, 39.262 Deg. N) GMT-8 hr std. time)
Obz Site: 39° 15' 7" N, 121° 2' 32" W, 2700 feet

Traveling in arid or desert country? Check your
boots well to see if you have a scorpion in them.
-- Survivorman, Discovery (SCI) Channel

Web Page: home.earthlink.net/~mtnviews

C. Crane's Twin Ferrite Antenna
 

On 1-Dec-2005, Phil Wheeler wrote:

Xref: number1.nntp.dca.giganews.com rec.radio.amateur.antenna:253561

BKR wrote:
Computers and computer components are regulated by the FCC.
They MUST NOT cause interferance to licenced radio services.
(like the radio stations you are trying to tune in.)
Make that clear to the vendor you got the power supply from!


Interesting thought but impractical. It could be the installation
(e.g., grounding) vs. the supply itself. Event if the PSU itself,
proving it would be a chore.

The noise from PC Power Supplies is usually radiated from the power cord and the house wiring. The
cause is often that the manufacturers cut cost by leaving out the L and C components of the line
filter. Usually you will find the place on the PSU circuit board to mount a bi-filar choke and two
or three capacitors. The capacitors are missing and the pads for the choke are jumpered. If you
can find an older junk PSU which has the components, just unsolder them from the junk board and
install them in your PSU. Sometimes the PSU's in Monitors have the filter components.

When I installed the filter in my old Pentium, the switch mode hash on broadcast band stations went
down by 30 db. Installing line filters outside the CPU Case had very little effect.

-ken-

C. Crane's Twin Ferrite Antenna
 

Ken Fowler wrote:

On 1-Dec-2005, Phil Wheeler wrote:


Xref: number1.nntp.dca.giganews.com rec.radio.amateur.antenna:253561

BKR wrote:

Computers and computer components are regulated by the FCC.
They MUST NOT cause interferance to licenced radio services.
(like the radio stations you are trying to tune in.)
Make that clear to the vendor you got the power supply from!


Interesting thought but impractical. It could be the installation
(e.g., grounding) vs. the supply itself. Event if the PSU itself,
proving it would be a chore.


The noise from PC Power Supplies is usually radiated from the power cord and the house wiring. The
cause is often that the manufacturers cut cost by leaving out the L and C components of the line
filter. Usually you will find the place on the PSU circuit board to mount a bi-filar choke and two
or three capacitors. The capacitors are missing and the pads for the choke are jumpered. If you
can find an older junk PSU which has the components, just unsolder them from the junk board and
install them in your PSU. Sometimes the PSU's in Monitors have the filter components.

When I installed the filter in my old Pentium, the switch mode hash on broadcast band stations went
down by 30 db. Installing line filters outside the CPU Case had very little effect.

-ken-
I was in the HSC store in Sacramento and discovered some filters that were
inside the AC switch. I decided against them, since I wasn't sure about the
amperage. I would think though the chassis builder might include such
devices, but haven't checked. Tomorrow I'll order the corcom filter 10ek7 10
amps that someone suggested from a place in San Jose, CA. $5.00. I'll give
that a whirl. Looks like I'll have to cut the cord to put it in the line.

--
Wayne T. Watson (Watson Adventures, Prop., Nevada City, CA)
(121.015 Deg. W, 39.262 Deg. N) GMT-8 hr std. time)
Obz Site: 39° 15' 7" N, 121° 2' 32" W, 2700 feet

Traveling in arid or desert country? Check your
boots well to see if you have a scorpion in them.
-- Survivorman, Discovery (SCI) Channel

Web Page: home.earthlink.net/~mtnviews

C. Crane's Twin Ferrite Antenna
 

This is really weird. The noise stopped! There's no question that when I
first noticed this some weeks ago that it was linked to turning the PC on,
and would disappear when I turned it off. I haven't changed anything.

--
Wayne T. Watson (Watson Adventures, Prop., Nevada City, CA)
(121.015 Deg. W, 39.262 Deg. N) GMT-8 hr std. time)
Obz Site: 39° 15' 7" N, 121° 2' 32" W, 2700 feet

Traveling in arid or desert country? Check your
boots well to see if you have a scorpion in them.
-- Survivorman, Discovery (SCI) Channel

Web Page: home.earthlink.net/~mtnviews

C. Crane's Twin Ferrite Antenna
 

This is really weird. The noise stopped! There's no question that when I
first noticed this some weeks ago that it was linked to turning the PC on,
and would disappear when I turned it off. I haven't changed anything.

Evil spirits on vacation ......???????

I presently have a severe noise problem on HF ...... every year at this
time .......

Chi-Com Christmas displays ?????? I hope your noise stays away for good
..

Merry Christmas all ..... 73 Tom KI3R Belle Vernon PA