Softrock Lite 6.2
Adventures in Electronics and Radio
Elecraft K2 and K3 Transceivers
December 2008 Archive
31 December 2008
Thanks to Dave, G3TJP, for letting me know that my new
page Inductor Choice for
Band Reject Filter was mangled.
I use Microsoft's Front Page to prepare and publish my web
site and for a reason that remains unknown to me, it decided to swallow several
paragraphs of text. I've rescued the page, which required copying the mangled
material into Notepad and then pasting it back into Front Page, followed by
reformatting to the way it should have been, upon which it became visible. Of
course, the original test displayed perfectly in Front Page's "design" mode
which leads me to suspect a bug in the way Front Page creates HTML from the
design mode entries.
I also can't say that I care much for how my equations are
rendered in Firefox. I create them in Microsoft Word with Equation Editor
and then copy/paste into Front Page. Instead of being rendered in nice fonts,
they are converted into bit-mapped images with the usual jagged blocky
appearance. Internet Explorer, in contrast, has fewer jaggies and a less blocky
appearance. I'm sure there's a way to do all of this more elegantly, but
there's a limit on my time and interest in learning yet another piece of
I understand that Microsoft has dropped Front Page and is
pushing another HTML editor, so perhaps my problems are not unique.
30 December 2008
As the year 2008 draws to a close, I've been working more
on several new kits. One is an AM broadcast band rejection filter. I've added a
new page discussing (at great length) why I picked the particular inductor cores
that I did for the filter. You may read the page by clicking
here or via the page
links at the left.
If you are interested in purchasing one of these filters,
drop me an E-mail at
Jack.Smith@cliftonlaboratories.com. I'll have more details in the spring as
the other kits are finalized. At the moment, I believe the AM band reject filter
kit will require the builder to have a method of accurately measuring
inductance, such as a Q-meter or AADE's LC meter. I plan on providing a set of
wound and measured inductors as an option for kit builders without this
test gear, as well as assembled and swept filters.
The filters will include a painted die-cast enclosure,
which is not shown in at the linked page. I'll have full details including price
and availability in the next month or two.
21 December 2008
I've added a new page
K3 Power Setting Accuracy with the
results of measurements I've made of my Elecraft K3's output power versus
commanded power level. Updating the K3's firmware to the most recent version and
recalibrating the power associated parameters improved the agreement
between commanded and measured power levels, but there remains a consistent
error trend associated with power level and frequency.
16 December 2008
JFETs are notorious for having wide parameter spreads.
It's not uncommon to see a 3:1 or even 5:1 ratio between the maximum and minimum
parameter values. I've spent the day measuring a collection of JFETs to
see how much variation in transfer characteristics might be found. The details
are at JFET Variation.
08 December 2008
I've added a new page
WWV Short Term Jitter looking at changes in time of arrival of WWV at 10 and
5 MHz. Why look at this? It can tell us a bit about how signals arrive in terms
of how many reflection points exist and also how much technology has changed
since the 1959 HP Journal suggested the method I implemented. I've also used the
measured data to calculate the distance between Ft. Collins CO and Clifton VA.
05 December 2008
I've corrected and expanded the discussion in using
LTspice to simulate non-linear capacitance at
Capacitor Voltage Change..
05 December 2008
I've added a significant section to my earlier page on
capacitance change with voltage Capacitor
Voltage Change to provide distortion data for Y5U ceramic, ceramic monokap
and polyester parts (0.1uF) with and without DC bias. The new data and
discussion is at the bottom of the page.
04 December 2008
I have an answer to the E-mail problem covered in
yesterday's comments�when updating my storage space quota, XO turned off the
"forward to main account" option for un-identified E-mail messages. I've now
re-enabled the function. This option is not located in the normal E-mail setup
and management page in XO's account access, explaining why I couldn't find the
option selection yesterday. A helpful E-mail from XO support pointed me in the
Since re-enabling the option yesterday evening, about 14
hours ago, I've received 114 junk messages sent mostly to random names at
cliftonlaboratories.com. There's a delicate balance between the annoyance at
having to scan all these junk messages after they are filtered versus missing a
legitimate message mis-directed due to an error by the sender.
03 December 2008
This web site and my cliftonlaboratories E-mail are hosted
by XO Communications and I've never had a problem with either the site pages or
E-mail until a couple days ago. When setting up the Clifton Laboratories
account, I had opted for all E-mail messages, regardless of the name, to be
forwarded to me. This meant that messages that, for example, omitted the "dot"
and were sent to jacksmith instead of jack.smith made it through. This also
meant that hundreds of junk messages a day addressed to random names, such as
accounting or accountspayable at clifton laboratories also made it through.
However, Thunderbird, the E-mail client I use (and recommend), did a pretty good
job at sorting through these messages and filtering the crud into a separate
folder that I could quickly scan for legitimate messages.
However, beginning around the first of December, I noticed
a major drop in these unwanted messages going to cliftonlaboratories addresses.
I didn't think too much of this until I realized today that receiving almost no
junk messages after typically seeing 100-200 per day meant that something
It seems that XO changed my account to block all messages
except those addressed to names that I have specifically identified as valid.
I've asked XO whether this is a new system-wide policy and if not how I might
return to receiving all messages, regardless of name, but have not yet
received a response.
This is a long way of saying that anyone who has sent a
message to me in the last three or four days and failed to receive an answer
should check the address and re-send it to jack.smith.
I've also had XO update my account to increase the storage
from 250 MB to 2 GB. This will allow me to post higher resolution images and the
like. (Believe it or not, I had used nearly 90% of the 250 MB limit at this site
as of the end of November.)
I hope to have a new page with updated non-linear
capacitance measurements completed tonight or tomorrow.
03 December 2008
As usual, I've moved the November 2008 Updates page to
archives, reachable by clicking here or via the
table at the top of this page.