Elecraft

K144XV Strange Readings

Classic

List

Threaded

8 messages Options

Michael Eberle

K144XV Strange Readings

I've noticed strange behavior on both the W2 watt meter and a
cross-needle meter when using my K3 on 2 meters. Just curious if anyone
has had problems like this? In SSB mode, keying the mic without any
audio causes the watt meter to show about 3 watts output power and 3:1
SWR. However If I hold the TUNE button and put out a carrier It shows
the expected 7-10 Watts forward with normal low SWR. It also appears to
show normal readings while speaking into the mic, but goes to the
unusual readings with in between audio peaks.

Thanks
Mike KI0HA
______________________________________________________________
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

Chad Wasinger

Re: K144XV Strange Readings

Mike - yes, I've seen the same thing. I can't put my finger on it either but when using the k144xv with my wattmeter, I have high SWR always. Normally I can still run the 5-7 watts into an amp without issues but there are times this high SWR trips things off.
Elecraft - it would be nice to finally understand what needs to be done to correct this issues. Very common among the users that are on SSB/CW, not so much FM.

> Date: Fri, 17 May 2013 05:26:24 -0500
> From: [hidden email]
> To: [hidden email]
> Subject: [Elecraft] K144XV Strange Readings
>
> I've noticed strange behavior on both the W2 watt meter and a
> cross-needle meter when using my K3 on 2 meters. Just curious if anyone
> has had problems like this? In SSB mode, keying the mic without any
> audio causes the watt meter to show about 3 watts output power and 3:1
> SWR. However If I hold the TUNE button and put out a carrier It shows
> the expected 7-10 Watts forward with normal low SWR. It also appears to
> show normal readings while speaking into the mic, but goes to the
> unusual readings with in between audio peaks.
>
> Thanks
> Mike KI0HA
> ______________________________________________________________
> 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

Michael Eberle

Re: K144XV Strange Readings

In reply to this post by Michael Eberle

I have the same problem even running it with an amp. I wondered if maybe somehow some of the 10M IF was coming through causing the meter to show SWR. But during modulation, the higher power 2 meter signal caused the meter to display correctly.

Sent from my U.S. Cellular® Smartphone

-------- Original message --------
From: Chad Wasinger <[hidden email]>
Date: 05/17/2013 7:12 AM (GMT-06:00)
To: [hidden email],[hidden email]
Subject: RE: [Elecraft] K144XV Strange Readings

Mike - yes, I've seen the same thing. I can't put my finger on it either but when using the k144xv with my wattmeter, I have high SWR always. Normally I can still run the 5-7 watts into an amp without issues but there are times this high SWR trips things off.

Elecraft - it would be nice to finally understand what needs to be done to correct this issues. Very common among the users that are on SSB/CW, not so much FM.

John Lemay

Re: K144XV Strange Readings

In reply to this post by Chad Wasinger

I'm sure this issue was raised only a week or two ago - worth checking back
?

John G4ZTR

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of Chad Wasinger
Sent: 17 May 2013 13:12
To: [hidden email]; [hidden email]
Subject: Re: [Elecraft] K144XV Strange Readings

Mike - yes, I've seen the same thing. I can't put my finger on it either but
when using the k144xv with my wattmeter, I have high SWR always. Normally I
can still run the 5-7 watts into an amp without issues but there are times
this high SWR trips things off.
Elecraft - it would be nice to finally understand what needs to be done to
correct this issues. Very common among the users that are on SSB/CW, not so
much FM.

______________________________________________________________
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

AD6XY

Re: K144XV Strange Readings

This post was updated on .

In reply to this post by Michael Eberle

Its oscillating. Please stop using it as you are transmitting outside the band - hence the high VSWR.

You need to speak to Elecraft Tech. There is a simple mod that works in some cases. I have seen several of these now. Something causes the transverter to oscillate and produce a signal close to but outside the amateur band. It is easy to spot with a spectrum analyser. Sometimes the oscillation depends on the loading of the antenna. The high VSWR you see is because the antenna is a poor match outside its intended range. The settling with modulation is because when the 10m drive signal appears, it will often kill the oscillation and the transverter will appear to be working as intended.

Transmitting out of band is a bad thing to do as you could interfere with all sorts of important services, so it is best to not use the transverter if it is showing these symptoms. If you are using an amplifier you may be amplifying the problem. Even on FM, there may be a short burst of oscillation at the start of transmission before the drive signal appears.

Mike

Dave-3

Re: K144XV Strange Readings

In reply to this post by Michael Eberle

Both my early edition K144XV were not unconditionally stable and were swr
intolerant

I think you will find that the 3:1 swr is because it is oscillating "out of
band". Try listening on a scanner. I have experienced this on my two k144xv
and g4ddk had the same issue with his. One example produced 162MHz, one
168MHz one around 158MHz. When you tune or speak it stabilizes and generates
on 2m My k144xv were fine if I operated at the bottom end of 2m where the
swr was 1.1:1 but my antenna swr rose to 1.6:1 at around 144.8MHz and above
this point it showed the instability you mentioned

Mine were replaced with the later production run k144xv (the one without the
centre spacer, but that could just be coincidence!) and the issue has not
arisen since

Dave

G4FRE

Message: 19
Date: Fri, 17 May 2013 05:26:24 -0500
From: Michael Eberle <[hidden email]>
To: [hidden email]
Subject: [Elecraft] K144XV Strange Readings
Message-ID: <[hidden email]>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

I've noticed strange behavior on both the W2 watt meter and a
cross-needle meter when using my K3 on 2 meters. Just curious if anyone
has had problems like this? In SSB mode, keying the mic without any
audio causes the watt meter to show about 3 watts output power and 3:1
SWR. However If I hold the TUNE button and put out a carrier It shows
the expected 7-10 Watts forward with normal low SWR. It also appears to
show normal readings while speaking into the mic, but goes to the
unusual readings with in between audio peaks.

Thanks
Mike KI0HA

______________________________________________________________
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

Michael Eberle

Re: K144XV Strange Readings

Dave,

Yes that is exactly what it appears to be doing. My frequency counter
is showing RF at 153.600 MHz regardless of what part of the band it is
tuned to. I removed the K144XV Reference Lock Board and there was no
change. Is there anything that can be done to correct this, or do I
need to send it back to Elecraft? I just bought it 2 months ago so it
shouldn't be an early production run board.

Thanks,
Mike KI0HA

On 5/17/2013 6:50 PM, WW2R Elecraft wrote:

> Both my early edition K144XV were not unconditionally stable and were swr
> intolerant
>
> I think you will find that the 3:1 swr is because it is oscillating "out of
> band". Try listening on a scanner. I have experienced this on my two k144xv
> and g4ddk had the same issue with his. One example produced 162MHz, one
> 168MHz one around 158MHz. When you tune or speak it stabilizes and generates
> on 2m My k144xv were fine if I operated at the bottom end of 2m where the
> swr was 1.1:1 but my antenna swr rose to 1.6:1 at around 144.8MHz and above
> this point it showed the instability you mentioned
>
>
> Mine were replaced with the later production run k144xv (the one without the
> centre spacer, but that could just be coincidence!) and the issue has not
> arisen since
>
> Dave
>
> G4FRE
>
>
>
>
>
> Message: 19
> Date: Fri, 17 May 2013 05:26:24 -0500
> From: Michael Eberle <[hidden email]>
> To: [hidden email]
> Subject: [Elecraft] K144XV Strange Readings
> Message-ID: <[hidden email]>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> I've noticed strange behavior on both the W2 watt meter and a
> cross-needle meter when using my K3 on 2 meters. Just curious if anyone
> has had problems like this? In SSB mode, keying the mic without any
> audio causes the watt meter to show about 3 watts output power and 3:1
> SWR. However If I hold the TUNE button and put out a carrier It shows
> the expected 7-10 Watts forward with normal low SWR. It also appears to
> show normal readings while speaking into the mic, but goes to the
> unusual readings with in between audio peaks.
>
> Thanks
> Mike KI0HA
>
> ______________________________________________________________
> 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
>

hf4me

Re: K144XV Strange Readings

Will someone please describe this "center spacer" so I can verify whether it
is in mine or not?

Was it an active part of the circuitry? If I have it in mine can I just
remove it without any other modifications? Why does removing an inactive
part have any effect?

73, Jim KG0KP

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of Ron D'Eau Claire
Sent: Friday, May 17, 2013 10:20 PM
To: [hidden email]; [hidden email]
Subject: Re: [Elecraft] K144XV Strange Readings

Mike: First e-mail [hidden email] or call them (831-763-4211) for
further guidance.

As Dave says the center spacer was removed very early on when some stability
issues arose. I have an early pre-production board, but it was stable with
and now without that spacer. This sounds like something new but may be
something that you can tackle yourself.

73, Ron AC7AC

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of Michael Eberle
Sent: Friday, May 17, 2013 7:57 PM
To: [hidden email]
Subject: Re: [Elecraft] K144XV Strange Readings

Dave,

Yes that is exactly what it appears to be doing. My frequency counter is
showing RF at 153.600 MHz regardless of what part of the band it is tuned
to. I removed the K144XV Reference Lock Board and there was no change. Is
there anything that can be done to correct this, or do I need to send it
back to Elecraft? I just bought it 2 months ago so it shouldn't be an early
production run board.

Thanks,
Mike KI0HA

On 5/17/2013 6:50 PM, WW2R Elecraft wrote:
> Both my early edition K144XV were not unconditionally stable and were
> swr intolerant
>
> I think you will find that the 3:1 swr is because it is oscillating
> "out of band". Try listening on a scanner. I have experienced this on
> my two k144xv and g4ddk had the same issue with his. One example
> produced 162MHz, one 168MHz one around 158MHz. When you tune or speak
> it
stabilizes and generates
> on 2m My k144xv were fine if I operated at the bottom end of 2m where
the

> swr was 1.1:1 but my antenna swr rose to 1.6:1 at around 144.8MHz and
> above this point it showed the instability you mentioned
>
>
> Mine were replaced with the later production run k144xv (the one
> without the centre spacer, but that could just be coincidence!) and
> the issue has not arisen since
>
> Dave
>
> G4FRE