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David Heinsohn

XV144

Hello All

I use a K2 and have XV50 and 144. The XV50 seems to be working just
fine. However the 144 seems to have a problem. I live far enough away
from other operators and had a poor enough antenna that I've not been
able to find a test horse to talk to on two ssb or cw. finally made
that happen last week. What I found was that the transverter seemed to
be working. Receive performance is not as good as I think it should be
(I changed out the loop antenna for an eleven element beam fix pointed
at the metro area about 100 miles away). I need to run with the preamp
on, rf and af gains all the way up to hear BIG stations at 100 miles in
good conditions. And even more worrying is that, based on several
stations reports my dial reads 12.4 khz high.

From what I can see in the manual there is no alignment for frequency
readout as such and the adjustment available from the TRN menu is only
10 khz.

In checking the K2 against WWV it seems to be within well less than
100 hz.

Suggestions?

TNX
de
David

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Jim Wiley-2

Re: XV144

David -

How high is your antenna? If your antenna is 20 feet or less above the
ground, it is well below the radio horizon for stations 100 miles away.

In fact, not allowing for various forward scatter propagation modes, an
antenna 20 feet above average terrain will "talk" about 6 miles. 100
feet = 15 miles, and for 100 miles, 5000 feet above average terrain.
Keep in mind that tropospheric scatter or other modes can extend these
distances quite a bit, and the numbers assume the distant antenna is at
zero elevation.

Obviously, if the distant antenna is elevated the required height at the
"near" end becomes less, or the range the two stations can communicate
becomes greater. This is the obvious reason that repeater sites are
often located on mountain tops. One of our local repeaters is located
on a mountain at about 4400 feet elevation, and it covers out to about
75 miles, using a 10 watt transmitter.

Absent the frequency readout problem, your transverter may be working
just fine.

- Jim, KL7CC

David Heinsohn wrote:

> Hello All
>
> I use a K2 and have XV50 and 144. The XV50 seems to be working just
> fine. However the 144 seems to have a problem. I live far enough away
> from other operators and had a poor enough antenna that I've not been
> able to find a test horse to talk to on two ssb or cw. finally made
> that happen last week. What I found was that the transverter seemed to
> be working. Receive performance is not as good as I think it should be
> (I changed out the loop antenna for an eleven element beam fix pointed
> at the metro area about 100 miles away). I need to run with the preamp
> on, rf and af gains all the way up to hear BIG stations at 100 miles in
> good conditions. And even more worrying is that, based on several
> stations reports my dial reads 12.4 khz high.
>
> From what I can see in the manual there is no alignment for frequency
> readout as such and the adjustment available from the TRN menu is only
> 10 khz.
>
> In checking the K2 against WWV it seems to be within well less than
> 100 hz.
>
> Suggestions?
>
> TNX
> de
> David
>
>
> -----
> No virus found in this message.
> Checked by AVG - www.avg.com
> Version: 10.0.1392 / Virus Database: 1520/3862 - Release Date: 08/27/11
>
> ______________________________________________________________
> 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
>
>

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Colin VE3MSC

Re: XV144

In reply to this post by David Heinsohn

You might want to contact Elecraft for a different variable inductor
or crystal for the XV144. I had the same problem months back, and
they discovered that they were shipping the wrong xtal for the 144.
73 Colin VE3MSC

At 08:21 AM 2011-08-28, David Heinsohn wrote:

>Hello All
>
> I use a K2 and have XV50 and 144. The XV50 seems to be working just
>fine. However the 144 seems to have a problem. I live far enough away
>from other operators and had a poor enough antenna that I've not been
>able to find a test horse to talk to on two ssb or cw. finally made
>that happen last week. What I found was that the transverter seemed to
>be working. Receive performance is not as good as I think it should be
>(I changed out the loop antenna for an eleven element beam fix pointed
>at the metro area about 100 miles away). I need to run with the preamp
>on, rf and af gains all the way up to hear BIG stations at 100 miles in
>good conditions. And even more worrying is that, based on several
>stations reports my dial reads 12.4 khz high.
>
> From what I can see in the manual there is no alignment for frequency
>readout as such and the adjustment available from the TRN menu is only
>10 khz.
>
> In checking the K2 against WWV it seems to be within well less than
>100 hz.
>
> Suggestions?
>
>TNX
>de
>David
>
>
>-----
>No virus found in this message.
>Checked by AVG - www.avg.com
>Version: 10.0.1392 / Virus Database: 1520/3862 - Release Date: 08/27/11
>
>______________________________________________________________
>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

John Ragle

Re: XV144

In reply to this post by David Heinsohn

Hello, David...

You raise two issues. Let me mention the dial reading issue first.
Elecraft has a mod that allows the LO in the XV144 to be pulled a bit.
In the K3 there is also an internal (to the K3) adjustment to correct
for the offset, but it was not sufficient to bring my XV144 anywhere
near the proper frequency. I am not sure about the situation for the K2.
Someone (e.g. Don) will chime in with that info.

The Elecraft mod is a slug-tuned inductor that installs in place of the
strap over near the LO crystal. Consult with Elecraft about this
problem; they are equipped to deal with it immediately and simply. My
XV144 was very far off frequency when assembled without this mod,
despite the fact that the LO crystal was marked to be of the proper
frequency, and the mod fixed things properly.

With respect to range, I see you are in Kansas. Around Elmdale, things
are pretty flat, so you should have no problems working out to 100 miles
with the 11 element beam -- your ERP will be of the order of several
hundred watts in the main lobe, assuming you are running the XV144 wide
open. Here in *(quite hilly*!) western New England I have no trouble
working out 100 miles with the XV144 running barefoot, as long as
conditions are normal. Usually to go any further than that, I have to
turn on the heat...350 watts to an 11 element beam at 38 feet does
wonders for a range increase. Of course, trying to use ssb in marginal
conditions only makes matters worse*;* CW is a marvelous communications
enhancer...

My conclusion from your observations is that you are correct...there is
a problem on the receive side of your set-up. Just where to look, I am
not sure. I assume you have checked the alignment on the receive side of
the transverter. Mine is plenty sensitive, working into a K3...it
compares equally to an ICOM 910H with a GaAsFET preamp on the same
antenna. Questions you might ask, are "is it poor sensitivity you are
dealing with?" or "is it that the signal level to the K2 IF that is low?"

I am sure that as the day wears on, someone else will chime in with a
constructive suggestion...

John Ragle -- W1ZI

=====

On 8/28/2011 8:21 AM, David Heinsohn wrote:

David Heinsohn

Re: XV144

To all who have replied so far, thank you. It looks like I'll be
making a call to Elecraft in the morning for the mod kit. That will
certainly help.

After I get the mod kit installed I will go thorough the entire
alignment procedure again paying particular attention to the sensitivity
portion.

Using the range nomograms from several sources, like the ARRL VHF
book, and the indicated performance of the stations in the Kansas City
area, this setup should be able to work that path with no enhancement.
It won't be strong but should be reliable. Thus KC seems to be a good
location for the other end of my test path. I may find I just need to
add another preamp. (The transmit power won't hurt either.)

I was concerned that I had a problem with coax or connectors as well,
so after I got the eleven element up, I got out the MFJ-269 and did a
sweep. I had a good solid dip at the expected frequency so the coax is
not acting like a dummy load.

Thanks again for the help,
David

-----
No virus found in this message.
Checked by AVG - www.avg.com
Version: 10.0.1392 / Virus Database: 1520/3863 - Release Date: 08/28/11

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Don Wilhelm-4

Re: XV144

In reply to this post by David Heinsohn

David,

On the frequency problem, order the no charge mod kit XV144MDKT from
Elecraft and install it. That will install a variable inductor in the
oscillator to allow you to pull the crystal into range (if not right on
frequency).

100 miles is a long distance on 2 meters.
You really need something to compare the receive with, the XV144 may be
working OK. It is really hard to tell whether it is working adequately
or not without doing some sort of measurement or comparison with a 2
meter receiver known to be working normally.
You should not normally have to turn the preamp in the K2 on, nor should
you need to turn the AF Gain up all the way. How high is that 11
element beam?

73,
Don W3FPR

On 8/28/2011 8:21 AM, David Heinsohn wrote: