The problem with the K2 headphone jack has nothing to do with neither
mono or stereo nor with the contacts. There is a built-in independent
switch at the back of the jack body whose activating arm breaks and the
the path to the speaker remains open after the headphone plug is
Take a look at the use of the Yaesu FT-900 knob on my K2 - see my website
www.qsl.net/w3fpr for details.
I recently updated with Yaesu's new phone number for the US - you might want
to look at www.yaesu.com to see where you contact for the UK.
If you want the FT100 knob
(smaller but with
you are making other plans
(John Lennon wrote it in a book, Mike Cross used it in a song - I don't know
who was first)
- Original Message -
From: Vic Rosenthal [EMAIL PROTECTED]
To: Don Wilhelm [EMAIL PROTECTED]; Elecraft firstname.lastname@example.org
Sent: Wednesday, June 09, 2004 3:50 PM
I suggest you build the RF Probe provided with the K2 kit. Use the probe
and your DMM to determine where the RF is being lost.
In transmit mode (TUNE), you should find RF in ever increasing levels at the
Xmit Mixer - U10 pin 4
Xmit Buffer - U9 pin 6 (and input to
There is not much on the Control Board that connects to pins 29 and 30 -
these are the DOT/PTT and DASH lines and they connect directly to pins 17
and 18 of P3 (they also connect to 2 resistors of RP4).
Check carefully for any solder bridges at the pins of P3, the U6 socket and
I would guess that the Yaesu speaker is 8 ohms impedance (that is a quite
common impedance) - a 4 ohm speaker like that used for the K2 internal
speaker will allow more power than an 8 ohm speaker.
The efficiency of the speaker has a lot to do with how loud it sounds too.
The 1/8 watt 1 meg resistor does two things - it provides leads to which one
can solder the very fine toroid wires, and it provides mechanical 'holding
power' for the toroid core. The resistance itself is not critical because
it is almost an insulator compared to the other impedances at
There IS one reason to generate the SSB signal as LSB - many crystal lattice
filters (including the one in the KSB2) have a steeper slope on the low
frequency side, so the LSB generation is better than USB generation. Yes,
the sideband CAN be inverted by the proper mixing scheme - the current
Do check the capacitor values to be certain they are correct in the BFO area
(C173 and C174 in particular as well as the correct varactors at D37 and
D38 - 1SV149, the smaller ones with the flattened 'rounded' side)!!!
You are less than 300 Hz deficient on the low end, and that is not
I just looked at my old copy of the NEW Sideband Handbook by Don Stoner
W6TNS, copyright 1958 - I have 6th printing dated June 1966.
Page 94 shows the schematic of the Central Electronics 10B phasing exciter -
and it DOES generate SSB at a fixed 9 MHz (unchanged from the 10A). The
addition of a
Jim and all,
I have worked on about 5 K2s since I acquired my XG1, and I can state that
the gain of a properly aligned K2 from the antenna through the IF amplifier
is very close from one K2 to another. Filter alignment will account for
Also, since I have been experimenting with
While I can't think of any definite reasons, but it sounds like you are
hearing a carrier somewhere near where the K2 input is tuned (28 mHz band).
One question - have you updated your KPA100 with the recent changes or do
you have a recent KPA100? If not, an artifact from the crystal
Eric and all,
That 50 ohm power resistor you are using will be highly inductive - it is a
wirewound type, meaning it is a coil of resistive wire. Yes, it measures 50
ohms at DC, but for AC, the resistive (and reactive) value depend on the
frequency of operation.
For those wishing to save a buck
Brian and all,
If the resistance reading should be 500 and one measures something LOWER
than 500 ohms it SHOULD be something to check carefully - it is the reading
that are higher than 500 that are 'no big deal'.
The more commonly asked question is from folks who measure something
If you have the post 3000 circuit boards, the proper answer is - yes, you
can build from the Rev F manual - BUT there is one cut trace on the RF board
that is not cut on yours (that cut is mentioned in the first column of page
52 of the Revision F manual as having been cut at the factory). The
Yes, I too would believe D36 is broken - it is quite fragile and will crack
if the leads are bent too close to the glass body - HANDLE WITH CARE.
You can temporarily substitute a 1N4007 diode until you can obtain a
replacement (the 1N4007 was used in the D36 location until the keying
I would say to save your money - unless you want to accumulate some parts
for other homebrew projects.
Parts in the K2 rarely fail (almost never) unless they are abused in some
The design point for the components is conservative and little stress is
placed on them in normal
Steve and all,
I don't usually disagree with you Steve, but I looked at my APP cables that
DO work FB with my KPA100 and they look just like the pictures in all your
Yes, if one looks at the the KPA100 input, it may look like it is reversed,
but it DOES mate properly with the cables
My observation with D36 is that attempting to bend the leads close to the
glass body (like most of the other diodes) can cause the glass to fracture.
The holes for D36 require the leads to be bent approximately 1/8 inch from
the body, and if the leads are bent right up to the glass, there will be
I have just posted an article detailing how to add a fixed audio output to
the K2 to my website www.qsl.net/w3fpr
This small PC board will provide up to 3 volt p-p (1 volt rms) out with a 50
microvolt signal at the antenna of the K2 and should serve the needs of
anyone wanting an output
Ron and all,
I bend component leads just like Joe - hold my thumbnail where I want the
bend, grasping the component between the thumb and forefinger.
That method has not broken any so far. I have only broken a part when I
approach them with something hard like pliers. Each to his own!
Elecraft continually improves things - we all know that. So now you will
find R50 and R58 on the strip of resistors - at least they were that way for
SN4192 when I assembled it. Yes, it has not always been that way - those
resistors were previously shipped loose in the RFb bag, so your
I have had many asking if I can take PayPal payments - and the answer is
yes, IF and only if those payment come from your PayPal funds or a bank
account. I have only a personal PayPal account and I don't want to upgrade
to a business account just for this project and pay the resulting
The initial re-tightening seems to be all that is required.
I believe the thermal pads will slightly thinner after an initial period of
being exposed to the pressure from the initial tightening and that normal
'squeezing' process may be shortened by the thermal cycling. I have not
been able to
From my observations, if the lower order digits on the frequency display are
different than .00 when you switch to 1kHz tuning steps, those
undisplayed digits will stay the same as they were. - in other words, if you
were tuned to 7070.35 and go to the 1 kHz tuning the steps will be to
Joe and all,
That is my favorite portable antenna too. In a pinch you don't need 3
supports, 1 will do to hold up the center. The 2 antenna wires and the
feedline CAN also be used as part of the guys to hold the center pole
upright and you have an inverted VEE - OR with one half of the antenna
Michael and all,
Yes, because the K2 has independent BFO adjustments for USB and LSB you must
know that both BFOs have been properly set before you can do 'tone matching'
to determine the correct dial setting. It IS a good method to verify that
one has achieved correct calibration, but if the
To: Linden, Mike (BRC-Hes) [EMAIL PROTECTED]; Don
Wilhelm [EMAIL PROTECTED]; email@example.com
Sent: Wednesday, July 07, 2004 6:11 PM
Subject: Re: [Elecraft] K2 Frequency Calibration
Isn't the tone alternation of WWV between 400 and 600 Hz? It used to be.
This IS the N6KR method that I have become so fond of (add an 'l' to the
link below). Wayne was the originator of this method and Tom has done a
good job of documenting it.
I will still stick with my favored method of observing zero beat (looking at
the tone frequencies with Spectrogram)
Mike has spotted a mounting problem with my Fixed Audio Output board in the
K2/100 with the new speaker shield. I am sorry I didn't realize the
problem - I tried it with my KPA100 without the speaker shield and it did
Mike has found a realistic mounting location, although it may not
From your description, the inverter you described is almost correct BUT it
won't work because there is no voltage available to it.
The output from the KPA100 is a HEXFET open 'collector' - which means it
makes a path to ground when active (transmit state) and is open during
Something is wrong - 1/4 inch screws should be plenty long - dumb question,
are you really using the 1/4 inch screws? - they are NOT the black ones.
The only thing the screw should pass through is the lockwasher and the
transistor (yes the thermal pad too) before it hits the heatsink.
For those wanting to build a post 3000 SN K2 to the latest level without
going through the interim steps of building as instructed FIRST and THEN
adding the changes to bring it up to level...
You already have a Rev E manual - go to the Elecraft website and download
the REV F manual and print pages
You are hearing the PLL reference transitions (Sverre explained it nicely),
but they should be at a low level and not very noticable unless you listen
If you happened to run CAL PLL without the bottom cover in place, those
clicks will be louder than normal - so re-run it with the
It is not abnormal - the amount of out-of-hamband range may be slightly
different from one K2 to another.
You may be running out of VFO tuning even though the numbers change. If you
want to verify, check the voltage at the left end of R30 on the RF board.
If it is less than 0.5 volts or
Actually there is no real connection between hearing the same pitch when
switching between LSB and USB and proper filter alignment like there is with
CW and CWr.
The SSB passband will pass a wide range of tones even if the passband is
severely mis-aligned. The only observation one can
Adding options to the base K2 is relatively easy, and the option upgrades do
not occur as often as changes to the base K2 (the firmware upgrades related
to the K60XV are the one major exception I can think of).
My recommendation is for you to start with the base K2, the K60XV, the
Does anyone know where I can find detailed alignment instructions for a
I bought some Vishay precision non-inductive power resistors - 25 ohm, 50
ohm and 100 ohms 100 watt rating to use as dummy loads. I assembled them to
a proper heat sink and connected to an SO-239 with zero length
If your K2 'rocks' with the bail extended, the most likely cause is either
the bail mounting feet are not the same distance from the edge of the panel
or that the rear feet are not mounted an equal distance from the edge of the
heat sink. It only takes a small bit of misalignment to
I have not yet seen a reply on the reflector to your questions, so I will
try to give you some information.
The voltage at U5 pin 1 will depend on the reflected voltage sensed by D17
and the setting of R27 - if you are measuring the voltage under transmit
conditions, do you have a good
I can't speak for anyone else, but I just don't like the sound of any audio
DSP processor, particularly for CW use. They are good for digging signals
out very close to the noise level, but my ears find the KAF2 far less
irritating for extended operating periods.
It is more a matter of
You can't get much better or more simple than a dipole. Get it up as high
as possible and feed it with parallel line. 44 feet is a great length for
40 thru 10 meters and will do 80 meters in a pinch. Can you get one end to
the peak of the roof? That may give you the extra distance
I now have batch 2 of my fixed audio kits ready to ship.
If you are wondering what they are, check out my webpage www.qsl.net/w3fpr
The price for the full kit is $17.50 shipped USPS Priority mail,
$15.00 shipped 1st class mail. International Air Mail shipment - $17.50
This is the
You may want to look at my website article www.qsl.net/w3fpr dealing with
adding a CW PTT to the K2. The added PTT input will work both in CW and SSB
mode and will mute the receiver, but no RF will be produced - this will be
positively true in CW unless one also activates the paddle
I would not say that there is any 'magic' length for the feedline. Try what
you can do and see what works. If it ends up that the tuner has difficulty
matching the shack end on one or two bands, add some extra feedline and try
Depending on the matching range of your tuner, you may
The normal meaning of INFO 080 is that one of the firmware chips is not
talking properly with the MCU.
The first thing I would do is remove all options from the K2. If the Info
080 remains, take a look at the voltage supplied to the MCU and IOC as first
order of business (and check for 0
The 'RF Gain' in the K2 is actually an IF gain control and it only controls
the gain after the selective elements. All the stages ahead of the IF
amplifier operate at fixed gain levels.
In many receivers where the RF stage is gain controlled, my experience is
that the gain can be made
I would suggest looking carefully in the IF filter area. You found one bad
solder joint, so another one is quite likely. The last one I worked on with
similar problems had a bad solder joint on the SSB board at one of the 3 pin
headers - which reduced the signal getting to the IF
The most common failure point is a solder joint.
So first check soldering, then re-check the soldering, and finally check all
We will need more details of what works and what doesn't (what do you see on
the display, what do you hear in the headphones, and under what conditions,
Yes, it certainly seems like your AGC threshold could stand to be
re-adjusted. The recommended 3.8 volts will be close, but is not any magic
number - the proper setting will vary from one K2 to another. I have seen
good results with voltages as low as 3.6 volts, but none higher than 3.8
You will likely find the problem associated with the VRFDET signal
Also, if you recently did the keyclick mod, look at that work carefully for
proper components, good soldering, and parts added in the correct spots on
the back of the control board.
Recall that the RF voltage at one end of D9 will be only 1/8 of the voltage
at the other end - this is a resistive voltage divider. You really didn't
say how much RF voltage you had, so go on and check things out as follows:
First unplug the KPA100 and KAT100 and re-check. When the
I will agree with you wholeheartedly, except for the RF Ground part ---
In reality, RF ground has only to do with a zero impedance reference for RF
at the frequency of operation. It can actually be up in the air (example -
at the midpoint of a dipole, normally the dipole feedpoint), or at
I don't know why the ratio was changed in the first place, but I really
don't think it will make much difference in the signal level. You can try
re-winding it and see what happens. The biggest difference should be in the
termination impedance of the filter.
The 20/5 transformer has a
Is the frequency actually different in LSB or USB mode, or only for CW? CW
should offset the frequency by the sidetone pitch value.
If your K2 filters and BFOs are aligned properly, you should receive on the
same frequency as the carrier transmit frequency in SSB mode, for CW mode,
I too agree - Ordering parts from Elecraft is not only easy, but you do
receive personalized service too - Scott and Richard do a fantastic job,
part numbers help a lot to avoid ambiguities, but they are available and
receptive with information about a particular part should the part
I really can't speak for the folks at Elecraft, but ...
I take the fact that Elecraft has provided an Elecraft part number in the
manuals as 'living proof' that they DO understand they have a need to be in
the REPLACEMENT parts business. That assures continuing quality and
uniformity of the
SMT work requires some parts handling techniques and a few pieces of extra
equipment if one is to be successful. If you are going to be building
electronic equipment, it is something you may want to persue.
The first thing needed is to develop a gentle hand with the tweezers to
I like my FT 900 knob (see my website www.qsl.net/w3fpr), but this is the
one that needs the added 'drag' pad thickness, and has no depression for a
I have seen the rubber tire from the Yaesu FT-900 knob placed aroung the
stock K2 knob - it takes a wee bit of stretch, but it
Let me restate your symptoms first so you can ignore my answer if no
1). You have over 10 watts of actual power generated into your dummy load.
2). The K2 display shows only a small amount of power output
3). You are getting excessive current draw (HI CUR).
If ALL that is
Be certain the frequency counter probe is still working by plugging it into
TP3 again, then --
Check T5 to be certain you have well tinned leads and good solder joints.
Then check the orientation of D13. Check soldering on all components shown
in the schematic VFO section (RF board sheet
If you simply set the BFO as indicated in the manual, the answer is YES you
should crank up Spectrogram and adjust the transmit BFOs (FL1) for SSB - and
CW too if you have not done so.
Take a look at my website (www.qsl.net/w3fpr) article on K2 Dial Calibration
for detailed information.
Mouser has them - the designation is '78L05' for the low power package and
'7805' for the 1 amp version. Similar numbering is used for the low
power/high power versions of most all the 78xx 3 terminal voltage
With that generalization out of the way, Mouser's part number is
I am using the 2.2 kHz filter on my KSB2 with the KAF2 and have noticed no
problems with the low pass filter. There is a very slight difference in the
upper end of the audio when I measure the filters with Spectrogram (KAF2 in
vs. KAF2 removed), but it is not enough to cause me any
The important thing about the transformers is the turns ratio (assuming the
primary and secondary are adequately coupled - not a problem with toroids).
So there is no reason to re-wind them other than asthetics and other
- Original Message
8 volts on R30 usually means the VCO is not oscillating. Try your counter
probe on TP1 to see if there is any frequency indicated - if so, check that
the frequency is correct for the band you are on (likely 40 meters at this
stage of construction) - the low band edge frequencies are
Tom and all,
This method is good technically, BUT...
Since most digital mode software also has provision for PTT (yes, it
requires building a simple interface), I would never advocate the use of VOX
for digital modes except perhaps in an emergency - it is too easy to forget
to turn off the
I would suggest that you review the A to B mod on the Elecraft website
www.elecraft.com (Builders Resource area) before doing anything. Download
the A to B instruction manual and make a decision of which 'optional' mods
to install (I recommend all of them), and if you are not certain
The 4 band board will not work well with 80 meters (it becomes a '3 band
board' due to the low pass filter sharing), but may I suggest that you build
the 4 band board and then add a 2 band board with 80 meters as one band -
the other band can be 17 or 15 meters (the one that is missing
You will probably have to find the correct value by trial and error. I
would recommend setting CAL CUR to 4.0 (which conforms to the 'at least 3.5'
instruction) - or even more and then lower it one step at a time until the
message re-appears - more likely on 10, 12 or 15 meters. The actual
Bob, Earl and folks,
Earl's comments are correct, but CAL FIL must also be run before calibration
is complete. Each BFO must be changed by at least one 'notch' and moved
back to the same frequency (aqssuming the filters were properly set before).
The K2 must detect that each BFO has been changed
I have returned home and all is as good as expected for 6 days after
major abdominal surgery. Initial reports from my surgeon indicate that
he was able to remove the cancer tissue while disturbing only a small
area of the surrounding tissue. I still have a lot of recovery to do,
but I am
What stage are you in the assembly? And what is the error message?
I am certainly not in the Boston area, but perhaps I can help via email.
Bob Freedman wrote:
I continue to have problems with the assembly of a K2, and I am stuck
at an early step in the kit. All voltages,
My fixed audio output is just what it says - it provides a level of
audio OUTPUT from the K2 independent of the setting of the AF gain control.
It does nothing for the audio INPUT. The input (to the mic jack) is
what is depicted on the Tigertronics website. Note that the mic wiring
What you say is true, but the conditions expected for Mil-Spec equipment
are not typical for the average hamshack - the wires are not subject to
excessive vibration and flexing and are not handled on a daily basis.
As a result, I regard soldering APP connectors for ham station use a
Use the real serial port if you can. They are always more reliable than
If you must use the adapter, make certain you have the latest drivers.
I am wondering which way to plan for K3 updates -- USB port or serial port on
If that PC is a desktop, purchase a real serial port card and install
it. Much more reliable than any adapter.
I know that does not answer the Vista driver situation - someone else
will have to answer that question, but if that is the true situation, I
would guess that drivers will
Examine your operating desires for the correct answer for you. If most
of your operation is casual, the 5 pole filters will do just fine -
remember that the DSP provides the ultimate selectivity.
If you are heavy into serious contesting or DX chasing and other
situations where you will
I suggest that you review the K2 Dial Calibration article on my website
http://w3fpr.qrpradio.com and then do a full calibration run including
the SSB filters using Spectrogram.
If that does not correct it, then re-do the calibration. The VFO and
the BFO are about the only thing that
Perhaps the statement in the manual is a bit terse for the full meaning.
If the external counter and the internal counter read the same, then
there is no problem with the K2 internal counter.
With a frequency display significantly lower than 12090 kHz when the
(known good) counter probe
Tom and all,
That is quite contrary to my experience. The APP housings that I have
purchased (from both PowerWerks and West Mountain Radio) have dovetail
matings that need quite a bit of force to slide completely together, and
I lock them with a drop of SuperGlue. I never had one come
The K3 uses open collector outputs on the band data lines. If the
amplifier does not provide pullup resistors, the band selection will not
work because the amplifier never sees a logic high level.
That the K3 uses open collector outputs has the advantage of allowing
the Band Data
The frequency at TP1 (did you mistype? the PLL reference frequency is
read at TP1) does not seem to be a problem. 12090 +/- 30 kHz can be
anywhere between 12060 and 12120 kHz, so your value of 12099.73
certainly fits within that range - it is correct.
As for your receive problem, if
Check Lyle's answer yesterday to similar questions. It is a known
problem and the fix is being field tested right now. You can expect the
firmware release to fix it in about a week according to Lyle.
Joe Subich, W4TV wrote:
With the K3, the messages play fine, but
Sorry, I mistyped - Scott was correct, the PLL reference is measured at
TP3 while the VFO is measured at TP1.
It was too late in the morning to offer the 'morning coffee' excuse, and
I have no other.
Don Wilhelm wrote:
The frequency at TP1 (did you mistype? the PLL
The K2 looks for a frequency reading near 12,100 kHz when it starts the
CAL PLL sequence.
If yours is only going up to 11,959.64 kHz, that is not high enough.
Info 232 is a usual result if the initial frequency is too low.
Check your PLL reference oscillator range again (check at TP3).
Since you already have the KRC2 set up to switch your antennas, I would
suggest you use that with the K3. Connect the K3 ACC pin 2 (AUXBUS)
signal to KRC2 pin 6, connect the K3 Keyout signal (ACC pin 10) to KRC2
pin 9, and Ground (ACC pin 5 or 12) to KRC2 pin 1.
The KRC2 needs 12 volt
Just walk through the authorization steps - if you don't have an
internet connection, use the phone.
I have done it many times. The only thing they want to know is how many
machines your copy is running on - if the answer is 1, they will
authorize it. It sometimes takes a bit of effort,
Put the K2 into CW test mode (in CW, press and hold the MODE button),
set the power level to something above 11 watts - press TUNE and measure
the voltage at KPA100 U1 pin 5. The voltage will normally be close to
If the above measurement is correct and you still cannot
Check out this application note at the Elecraft website -
Each K2 is a bit different in the overall transmit gain, so for most
stable operation, the value of R98 must be determined experimentally.
Be aware that increasing R98 too
After 'RTC' appears in the menu, he must press the EDIT button until
OFF is displayed. Then he can rotate the VFO knob (or tap the BAND+
and BAND- buttons) to change it.
If the indication is -- instead of ON or OFF, then there is a problem
on the KAF2 board that must be corrected.
Sorry, but that does not help a lot - the operation in TUNE that you
describe in normal. TUNE (with the KPA100) normally controls power at
20 watts. If you enter TUNE and then turn the power control, it will
try to produce the power that is set on the power control knob.
The gain of
The most likely thing is that the sidetone source has been accidently
toggled to U6 - 25.
Enter the menu for ST-L and edit the parameter (press EDIT) - then tap
DISPLAY to toggle between the two sources. Stop when you hear sidetone.
MARY HAYS CARNEY wrote:
What does the K2 internal voltage (tap DISPLAY) read? How about during
If it is substantially lower than the voltage at the power supply, look
for a problem with the power cord or the connections to the supply or
even with the supply itself - substitute a charged
You should be able to use the 60/40 solder with no problem - I
understand that it is allowable for repair work in most countries.
Raymond METZGER wrote:
I am building my K3 kit and currently installing the KBPF3 module.
Unfortunately, one lead of
It all depends on your entire NVIS antenna system. A quarterwave
radiating element needs another quarter wave wire as a 'radial' or
'counterpoise' (the quotes are intentional). So, you end up with a
total of 1/2 wavelength in any case.
Why are you concerned about a reflector for an
If you have transmit power problems in CW mode or TUNE, then the only
part of the SSB opyion board that could cause that condition is Q1, Q2,
Q3 and the associated components.
Look at the KSB2 board schematic near the bottom and you will see which
components need to be checked.
T1 and T2 are not in the path for CW or TUNE, so they are not high on
the list of suspects for Lernart's situation.
OTOH, if the low power is on SSB (but CW and TUNE are good), then T1 and
T2 would be the prime suspects.
I had a similar problem
At low power settings, does the actual power output go up to over 12 watts?
If so, the diodes in the KPA100 wattmeter have been damaged (likely by a
lightning induced static).
Replace D16 and D17 in the KPA100 and you should regain power control
for both high and lo ranges. To
The E42 error means there is something wrong with the VFO - most likely
a bad solder joint or an improperly tinned toroid lead. Check the
schematic to determine the components in the VFO and examine them
carefully, resoldering where necessary.
Once you find the problem source, I
1 - 100 of 13051 matches
Mail list logo