Thanks Allison:

I also have the White Mountain 20 and WM-40
so I can check out those circuits. Will look for a new
rock for the PSK-40.
TNX AGN ES 73, Ken  AD6KA

Well at least that's better than the "Oh! Do you have
a "handle" and talk to truckers?" that I got when I
mentioned ham radio to a coworker...
Ken  AD6KA

Boy is that ever true!

During the ARRL DX SSB Contest my 756PROII went out.
I switched over to my backup, a TS-940S/AT.
It's an excellent radio with great sensitivity, but
I sure did miss the IF DSP filters of the PROII, especially
with the crowded bands. What a difference. Still, the 940
was my first ever "bought brand new in the box" rig and
I love it and will never sell it.
73, Ken  AD6KA

After an email with Malcolm, I think that I am going to
send it in and not try to fix it myself. According to Malcom:

"Troubleshooting is the hardest part.  The boards are 4 layers of traces,
only top and bottom are documented."

and:

"The sublogic is behind the front panel, the dc/dc converters
are on that board as part of it's circuitry, unidentified as such
.  They all convert a positive voltage to a negative
voltage.  Usually the Dc/Dc converter run ALC and s-meter circuits."

Looking for a fault in an unidentified circuit in a four layer
trace board is WAY beyond my capability. I can replace
a driver or PA transistor and tweak the proper bias and current
using the Service Manual, but the above I cannot do.
Discretion is the better part of valor.
I am going to let a pro do it.
Many thanks for the advice by all..
73, Ken  AD6KA

Many thanks for the advice, Clark and Vinnie.

Yeah, at least opening it up and looking for something
obvious, cleaning & tightening connectors and boards sounds like
a great idea. Nothing to lose there. I was just getting ready
to box this puppy up, glad I read these posts.
Will let you know if I find anything obvious amiss.

I will look at the schematic and see if I can find that
5v regulator.

TNX AGN ES 73, Ken  AD6KA

Hello To All:

I was operating in the ARRL DX SSB Contest this weekend.
Antenna is a roof mounted HF6V with good SWR's.
After about 100 successful contacts (barefoot) my PROII
began suddenly and quickly turning itself off during transmissions.
I thought perhaps RF was getting into the radio, but I have
operated this radio and antenna with an AL80A before and
never had this problem. After rig turning off, I turned off the power
supply (Astron SS-30M), turned it back on, and the radio would
boot back up again. (The PROI->III series takes about 10 seconds).
This happened about three more times. So I decided there
was a problem or intermittent in the power cord or PS. It checked out
OK on the DVM. Nevertheless, I didn't want to mess with it during
the contest, so I used another, almost new power cord and switched
to my backup PS, a Samlex SEC-1223. This worked fine for
a while then the problem happened yet again. This time however
the radio will not turn back on at all.

I have gone through the new power cord with the DVM and all
connections are solid and not corroded, fuses intact and in place.
I have tried the new power cord with the Astron too and the output
reads the proper voltage but the radio still won't turn on at all.

It may be my imagination, but when this problem first started
happening, when I turned on the PS power with the radio plugged
in, I THOUGHT I heard a slight relay type "click" from the PROII.
I admit I could be wrong about this.
Is there some sort of relay in the power switch rail?

So now the rig won't turn on at all no matter what I try.
Has this happened to you or anyone you knew?
And do you know what the problem turned out to be?
I am hoping and praying that it is something simple
and cheap like a resettable fuse that blew or maybe a
switch or diode.

I don't have the skills to hop on and troubleshoot this
rig, but something like a resetable fuse or diode I could check
and replace. I am very handy with a soldering iron, including
SMT.

Or perhaps it's best just to bite the bullet and send it
to Icom Service in Bellevue and have them go all the way
through it. $84 per hour service plus shipping and
insurance both ways.

Any and all thoughts and experiences appreciated.
TNX ES 73, Ken  AD6KA
PS: Finished the contest with my TS-940S/AT. Sweet
rig but boy did I miss the digital IF filters of the PROII.

Maybe try a master CPU reset?
Page 63 of the manual:
[HOME] + POWER on:
CPU master reset for all memories and default menu settings.

GL ES 73, Ken  AD6KA

Next time don't buy these components at Radio Shack.
Yes, they are very convenient but you can save a lot
of money shopping around.

Radio Shack charges $20.99 for a 4" 12vdc fan.
At All Electronics you can get a 12vdc 120mm fan (4.7")
for $4.25. And the metal fan guard you will need so you
don't whack your fingers is $1.60. (Not available at RS).
http://www.allelectronics.com/index.php?page=seek&id%5Bm%5D=pattern&id%5Bq%5D=120mm+fan&x=0&y=0
They also carry LED's, switches, project boxes, and
all sorts of components and spiffy stuff. At least get on
their catalog mailing list as their inventory changes.
If you plan to build more projects, you will always find
something you need at a great price at All Electronics.


So are you going to mount it under the dash in your Jeep?
With the fan blowing from the bottom up?
Some of these 2m rigs have a downward firing speaker,
I don't know how the fan would effect the sound.
you can always get an inexpensive small MFJ Extension Speaker.
They are about $13.99 and actually aren't bad.

Good luck with your installation!
73, Ken AD6KA

Then submit your log. Your logging program might be
able to export the log in Cabrillo Format, the default
contest logging format. However almost all logging programs are able to export a file in the Amateur Data Interchange Format (adif or adi). This page enables you to upload your adif format log file and convert it into the Cabrillo format required for submitting your log entry for the contest:
http://www.cqwpx.com/adif/
And there are other converson pages and programs.

With LogChecker you can edit, fill in the log, check Cabrillo Format and Header, convert files from the most popular logging software to Cabrillo and ADIF, print customizable files, calculate statistics, and export logs to RTF, PDF or HTML for publishing.
http://www.dxshell.com/logchecker.html

You can find where to submit your logs via email attachment
for a particular contest at most Contest Calendar sites like the
WA7BNM Contest Calendar. Don't wait too long after the contest.
Submission deadlines range from a week to a month after the contest,
http://www.hornucopia.com/contestcal/

All logs are always welcome. Even if you don't want to
enter the contest proper, your log is appreciated as a
"check log".

GL ES 73, Ken  AD6KA/5R8GQ

Perhaps you should also post this question on
the BITX20A Yahoo User Group?
http://groups.yahoo.com/group/ba_radio_builders/message/235
I built the BITX20A and the factory counter and it worked OK.
But I hooked up and now use an older AADE DFD1 LCD
counter instead, with the "Biggy" LCD option.
http://aade.com/biglcd.html
Just personal preference.
(Not sure if the current DFD1 model will work with the BITX)
73, Ken  AD6KA

Greets!

I have an older Small Wonder Labs PSK-40, the higher parts count version
with the DB-9 connector. (20m version was on the June 2000
cover of QST magazine) It is functionally a crystal controlled
SSB transceiver with slightly wider-than normal IF passband characteristics.
It covers the range of 7.070-7.074 MHz,
which was then the 40m PSK PSK calling area. Now
I notice that most, if not all, of the 40m PSK activity, especially
DX, is heard at or around 7.035.

What is the best way to change the frequency of this unit?
Switch out the LO crystal itself (11.981 MHz), or see if I can change
the LO or offset (4.915 MHz) frequency by changing the inductors in these
circuits? If I changed out the LO crystal would I have to change
anything else?

Any and all advice appreciated.
This is a terrific little unit and I don't want to butcher it.
73, Ken  AD6KA

Congratulations and welcome to HF!

While gear and antennas can always be upgraded,
now that you know you can make decent QSO's,
I would begin a program to work on improving your operating
and listening skills. Successful and satisfying ham
operating is not just about the gear, it's about your
skills, knowing your rig forward and backwards, and
applying certain techniques to certain situations.

Read, really read, the rig's manual from cover
to cover. Not just knowing what the controls
do but how that effects your real life operating.
I was fortunate to be an SWL for years before I
got into Ham Radio, so I had a lot of listening experience.
Still, I had to learn some more skills because of
receiver features on my ham rig that were not on
my SWL receiver.

Learning to LISTEN is a skill that will reward you with big payoffs.

Instead of tuning past signals that you
can't copy easily, stop on them and take it as a challenge
to try and dig them out, as an exercise. It's fun! (But don't call
them unless you can clearly hear them come back to you).

An exercise my Elmer had me do was to start at the bottom
of the band and tune across the band and ID as many calls
as I could, even if I had to stop and listen for 5-10 minutes to dig
them out. It is natural for us to gravitate towards the "big signals"
or "easy to copy signals" when tuning around. But if you hear
signals "down  in the mud", try everything you can to dig them
out. It worked for me. YMMV.

Experiment with using your rig's passband tuning,
notch filter, noise reduction or noise blanker,
preamp, and receiver gain control. Remember that
the preamp also raises the noise floor so is sometimes
not the way to go on a weak signal. Often you can copy
a signal better by turning the receive gain down.
I know it sounds counter intuitive but it often works!

Practice reducing adjacent signals (as best you can) on one or
either (or both) sides of the target signal using the passband
tuning  control or the manual Notch Filter. (Works best on CW
signals).

Also, look up "Grayline Propagation" on the Net and
familiarize yourself with what that is and how you can
use it for your benefit. There are some very cool and helpful
free software you can download that will show you the
current grayline on a spiffy map at any given time.
Google "Real time grayline map software" or something like that.

I am not all that familiar with the 570 but have played with
it some at the ham stores and it seemed to have a nice
receiver, intuitive to operate. I know I sure found it's receiver
much easier to operate than the MUCH pricier TS-2000.

Good luck and hope to hear you on the air.
73, Ken  AD6KA

What is the advantage of using Litz wire in these
applications instead of regular wire? I'm not familiar
with Litz wire and want to learn why it is better.
Just curious. Sounds expensive!

Thanks.
You learn something new every day!
73, Ken  AD6KA

I had the same problem running QRO RTTY into my
roof mounted vertical, but it was OPENING both my
garage door AND my next door neighbor's! The
strange thing is, at that time I had been in operating
in this house, with QRO, for five years. Very bizarre.

Turns out my station ground was disconnected! DOH!
That fixed it!
73, Ken AD6KA
PS: I like to use FT-240-31 or 43 toroid chokes
for these types of problems. Yeah, they are a lot
more money but they work better also.

Wow, I just looked at that tuner, $500 at Universal Radio,
rated to only 120 watts, and no meter.

You can get a perfectly good auto tuner (if that is the way you
want to go) from MFJ or LDG , with a meter, rated to
200 watts, and a built in balun for half that price.

And I highly doubt that it is "the best". You are only paying for
the Icom name, and Icom accessories are notoriously expensive.
(ALL factory accessories are expensive, but Icom is the worst).

Have fun building up your new ham shack!
73, Ken  AD6KA