Elecraft

Re: K3 VFO tuning noise

Classic

List

Threaded

7 messages Options

WO0W

Re: K3 VFO tuning noise

I notice noise when tuning near 28.004 when on a dummy load. When on an
antenna, the background noise at S1 level masks it.

73, Red
______________________________________________________________
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

Phil Hystad-3

Re: K3 VFO tuning noise

I am pretty sure that I would never be bothered by a noise that is easily masked by an S1 noise level.

On Dec 18, 2012, at 10:59 AM, WO0W <[hidden email]> wrote:

> I notice noise when tuning near 28.004 when on a dummy load. When on an antenna, the background noise at S1 level masks it.
>
> 73, Red
> ______________________________________________________________
> 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

______________________________________________________________
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

Bill Clarke

Re: K3 VFO tuning noise

So - I got curious and tested my rig for the "noise" on ten meters. It
is so faint that I had to use phones to be sure it was actually there. I
agree with Phil, this will never bother me. Perhaps this varies from one
rig to another?
______________________________________________________________
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

Jussi Eloranta

Re: K3 VFO tuning noise

On 12/18/2012 12:11 PM, Bill Clarke wrote:
> So - I got curious and tested my rig for the "noise" on ten meters. It
> is so faint that I had to use phones to be sure it was actually there.
> I agree with Phil, this will never bother me. Perhaps this varies from
> one rig to another?
On mine I can definitely hear it even with the band noise present (I
always use phones and work with fairly weak signals lurking in the noise).
When browsing the band quickly, it is possible to miss a weak station
because of this. I have a "decent" antenna hooked up to it - an inverted
V, which
is abt 50 feet up from the center, so there is significant band noise
present. I have the preamp on pretty much at all times on 10m.

I wonder if there are some factors in the assembly process that could
affect this (routing of cables etc.) ?
I think I have also noticed that the amplitude of the tuning noise
varies (not related to the noise level of the band) but
I still have to verify this observation (this could still be my
imagination).

As for the question about the RF gain - I probably need to calibrate RF
gain again. It would be great to know
how it got messed up - it could have been from the very beginning - I
might have just missed it.

Jussi (AA6KJ)

______________________________________________________________
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

Peter Lambert

Re: K3 VFO tuning noise

I've had the KX3 for a couple of months now and have heard the noise for the
first time just recently.
At the time I had no antenna connected to the unit whilst charging the
batteries and turned the knob and there it was. It was barely above the
noise level of the rig itself (which is awful quiet). Later that evening
the noise was gone - I simply could not hear it no matter what I did, 10m
through LF. Next day I could hear it again.
The noise came and went with temperature. We're into summer here and during
the middle of the day when it's stinking hot it's there, morning and evening
when it's cooler it's gone. Kind of "feels" like a bit of DC shift in the
direct conversion mixers with temperature that results in a low frequency
artefact when the digital VFO makes a step change in frequency.
In normal use, with an antenna, I can't hear it under any circumstances.
It's of no consequence (to me).
Regards, Peter VK4JD.

______________________________________________________________
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

Pete Smith N4ZR

Re: K3 VFO tuning noise

In reply to this post by Jussi Eloranta

What about hearing tuning noise in the main RX when the sub-RX is
tuned? In my case it is not discrete signals, rather an increase in the
noise, and is clearly audible over band noise on 10.

73, Pete N4ZR
Check out the Reverse Beacon Network at
http://reversebeacon.net,
blog at reversebeacon.blogspot.com.
For spots, please go to your favorite
ARC V6 or VE7CC DX cluster node.

On 12/18/2012 3:53 PM, Jussi Eloranta wrote:

> On 12/18/2012 12:11 PM, Bill Clarke wrote:
>> So - I got curious and tested my rig for the "noise" on ten meters.
>> It is so faint that I had to use phones to be sure it was actually
>> there. I agree with Phil, this will never bother me. Perhaps this
>> varies from one rig to another?
> On mine I can definitely hear it even with the band noise present (I
> always use phones and work with fairly weak signals lurking in the
> noise).
> When browsing the band quickly, it is possible to miss a weak station
> because of this. I have a "decent" antenna hooked up to it - an
> inverted V, which
> is abt 50 feet up from the center, so there is significant band noise
> present. I have the preamp on pretty much at all times on 10m.
>
> I wonder if there are some factors in the assembly process that could
> affect this (routing of cables etc.) ?
> I think I have also noticed that the amplitude of the tuning noise
> varies (not related to the noise level of the band) but
> I still have to verify this observation (this could still be my
> imagination).
>
> As for the question about the RF gain - I probably need to calibrate
> RF gain again. It would be great to know
> how it got messed up - it could have been from the very beginning - I
> might have just missed it.
>
> Jussi (AA6KJ)
>
> ______________________________________________________________
> 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
>

Edward R Cole

Re: K3 VFO tuning noise

In reply to this post by WO0W

Made a test tonight on my KX3 on 28-MHz:

First I tuned my triband yagi to SWR 1.5 using my Drake MN2000
antenna tuner and then ran the KX3 auto-tuner to get a perfect
match. With preamp off I have to run AF gain up to 30 to hear
background noise and when I tune the VFO there is a mild popping
noise as the digital encoder it stepped up or down in frequency,.

Next I turned on PRE (set for 20 dB in the menu) and I can barely
hear the VFO over the white band noise as I tune. If I turn the AF
gain down (to 18) to hear the same level of background noise as with
the PRE off, then I am not able to hear any noise from the VFO.

Since I would normally use the preamp turned-on 10m, this says VFO
tuning noise is a "non-issue".

If I disconnect the antenna then VFO tuning noise is present
(background noise is down about 20-dB).

I use 28-MHz as my IF with a 2m transverter and never noted any noise
from the VFO. Conversion noise is higher than the VFO noise.

73, Ed - KL7UW
KX3-S/N 0475

______________________________________________________________
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