Elecraft

K3: 30M signal

Classic

List

Threaded

7 messages Options

Ken Kopp-3

K3: 30M signal

I have a strong carrier on 10.106.20 (zero-beat) signal that's
been present since I built K3 (S/N 56). It's significantly weaker
when I remove the antenna. I realize this signal may well be
originating in my immediate area, but I'd like to know if it's "out
there" somewhere. (:-) Does anyone else hear it?

The "fast-tuning" birdie utility has no impact on the signal.

Ken Kopp - K0PP
[hidden email]

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Don Wilhelm-4

Re: K3: 30M signal

Ken,

Not heard here, but I find a very weak signal on 10106.75. Since it
gets very weak when I remove the antenna - and is very strong if I just
use a wire to the antenna jack center conductor, it is something in the
shack (my antennas are more than 100 feet away). I suspect something
associated with the Ethernet cabling in the house, but I am not going to
shut it down to check.

The 'fast-tuning birdie removal tool' will not work on real signals
(those do not 'fast-tune').

73,
Don W3FPR

Ken Kopp wrote:

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

N5GE

Re: K3: 30M signal

In reply to this post by Ken Kopp-3

On Tue, 24 Mar 2009 20:18:05 -0000, "Ken Kopp" <[hidden email]>
wrote:

Yes, I hear it here in TX also, and as I recall I've heard it on many
RX's, not just the K3's. Mine is not so strong but it is aggravating
when trying to work someone there.

It might be a spur from something in both of our locations.

73,

>I have a strong carrier on 10.106.20 (zero-beat) signal that's
>been present since I built K3 (S/N 56). It's significantly weaker
>when I remove the antenna. I realize this signal may well be
>originating in my immediate area, but I'd like to know if it's "out
>there" somewhere. (:-) Does anyone else hear it?
>
>The "fast-tuning" birdie utility has no impact on the signal.
>
>Ken Kopp - K0PP
>[hidden email]
>
>______________________________________________________________
>Elecraft mailing list
>Home: http://mailman.qth.net/mailman/listinfo/elecraft
>Help: http://mailman.qth.net/mmfaq.htm
>Post: mailto:[hidden email]
>
>This list hosted by: http://www.qsl.net
>Please help support this email list: http://www.qsl.net/donate.html

Tom, N5GE
K3 #806, K3 #1055
XV144, XV432
W1 and other small kits.
http://www.n5ge.com

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Amateur Radio Operator N5GE

ab2tc

Re: K3: 30M signal

Hi,

Absolutely no carrier here in CNY on either of those two frequencies with or without antenna. *With* antenna lots of CW signals nearby though.

Radio Amateur N5GE wrote

On Tue, 24 Mar 2009 20:18:05 -0000, "Ken Kopp" <k0pp@rfwave.net>
wrote:

Yes, I hear it here in TX also, and as I recall I've heard it on many
RX's, not just the K3's. Mine is not so strong but it is aggravating
when trying to work someone there.

It might be a spur from something in both of our locations.

73,

>I have a strong carrier on 10.106.20 (zero-beat) signal that's
<snip>

WILLIS COOKE

Re: K3: 30M signal

In reply to this post by Ken Kopp-3

Ken, I hear it weakly on my Carolina Windom that runs right over my computer. I do not hear it on my SteppIR that is about 200 feet away and 67 feet up. From that I would suspect that it originates in my computer or possibly router.

Willis 'Cookie' Cooke
K5EWJ

--- On Tue, 3/24/09, Ken Kopp <[hidden email]> wrote:

> From: Ken Kopp <[hidden email]>
> Subject: [Elecraft] K3: 30M signal
> To: [hidden email]
> Date: Tuesday, March 24, 2009, 1:18 PM
> I have a strong carrier on 10.106.20 (zero-beat) signal
> that's
> been present since I built K3 (S/N 56). It's
> significantly weaker
> when I remove the antenna. I realize this signal may well
> be
> originating in my immediate area, but I'd like to know
> if it's "out
> there" somewhere. (:-) Does anyone else hear it?
>
> The "fast-tuning" birdie utility has no impact on
> the signal.
>
> Ken Kopp - K0PP
> [hidden email]
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list:
> http://www.qsl.net/donate.html

Jim Brown-10

Re: K3: 30M signal

On Tue, 24 Mar 2009 14:42:02 -0700 (PDT), WILLIS COOKE wrote:

>From that I would suspect that it originates in my computer or
>possibly router.

Ethernet terminals (computers, routers, switches, hubs) are well
known to generate interfering carriers on 30M, 20M, 15M, 10M, and
6M. The clocks are local to each system, so if you have neighbors,
it's common to hear a cluster of them around 14,029, 21,052, and
the low end of both 10M CW and 6M. Most, but not all, of the
signal is radiated common mode by the Ethernet cable. Some of it
is also radiated by wiring internal to the Ethernet terminal due
to lousy shielding.

The common mode part (nearly always a lot stronger than the
internal wiring) can be attenuated a LOT by winding 4-7 turns of
the Ethernet cable around a 2.4-inch toroid of Fair-Rite #43 or #
31 material. For long cables (more than about 1/4 wavelength), you
will need a choke at each end of the cable. Each cable attached to
the Ethernet hardware is capable of radiating the signal, so it
may need a choke. Linksys products are well known to produce a lot
of this trash.

If you hear more than one of these carriers, kill power to your
Ethernet router, switch, or hub to see which of those carriers
goes away. That's the only one that you'll be able to choke
(unless you are on really good terms with your neighbors). Now,
restore power to it and apply the chokes while you listen to the
strength of that carrier.

More info on this in http://audiosystemsgroup.com/RFI-Ham.pdf

73,

Jim Brown K9YC

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

k6dgw

Re: K3: 30M signal

Jim Brown wrote:

> Ethernet terminals (computers, routers, switches, hubs) are well
> known to generate interfering carriers on 30M, 20M, 15M, 10M, and
> 6M. The clocks are local to each system, so if you have neighbors,
> it's common to hear a cluster of them around 14,029, 21,052, and
> the low end of both 10M CW and 6M.

I host the wireless company's RAP on my tower and power it in exchange
for free HS Internet. It has two transceivers ... one for the backbone
[flat panel directional antenna, and an omni stick for all the
neighbors. It is about 2m below my beam, and I hear a close spaced pair
of signals on all the frequencies Jim mentioned. They are very weak and
only audible on my K2 and K3. They're in the noise on my TS-850 and
FT-847. The Cat5 cable comes down the messenger cable along with my
coax runs.

Strangely, 1KW into the beam or my low band antenna, the apex of which
is about 2m from the RAP, on any band, has no effect on the wireless.

73,

Fred K6DGW
- Northern California Contest Club
- CU in the 2009 Cal QSO Party 3-4 Oct 2009
- www.cqp.org
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html