Monday, November 21, 2011

Elecraft K2 - Serial Number 007239 Build. Day 17

Hours 0:44:00    Total Build Time:   37:45:00     Nov 21, 2011



Spent the evening installing ICs on the RF board.  Ran into another set of NE602 ICs (Double balance Mixer/Oscillators) that were replaced by SA612AN chips.  The replacement chips were not mentioned in the manual or Errata sheet for the manual.  This was not a problem since the replacement could be confirmed by searching the internet.

One of the steps included mounting the MC1350 Surface Mount IF amplifier IC.  The Surface Mount IC came already soldered to the PC board as shown.  Connector pins were supplied to mount the Surface mount PC board to the main RF board.

Surface Mount MC1350 IF amplifier

Adding ICs to RF board

Saturday, November 19, 2011

Elecraft K2 - Serial Number 007239 Build. Day 16

Hours 2:12:00    Total Build Time:   37:01:00     Nov 19, 2011


Finally finished the step installing the capacitors.  67 Capacitors in just on step on the RF board.  Man thats a lot.....


Lots of capacitors to install on the RF board.  This is just one step!



RF Board

RF Board

RF Board

   

Tuesday, November 15, 2011

Elecraft K2 - Serial Number 007239 Build. Day 15

Hours 0:45:00    Total Build Time:   34:49:00     Nov 15, 2011


It is slow going installing the capacitors. I think it is progressing slow because first I have to sift through all the capacitors looking for the one I need.  Next the capacitor is stuffed into the board in the correct position, and finally it is soldered.  I was able to install 10 capacitors tonight.


Capacitors installed on the RF board

Sorted capacitors
There are 57 remaining capacitors to install before I can move on to the next step.... This could take a while.

Monday, November 14, 2011

Elecraft K2 - Serial Number 007239 Build. Day 14

Hours 2:24:00    Total Build Time:   34:04:00     Nov 14, 2011


Well, it had to be done some time....   I came to the step in the construction of the RF board where the capacitors are loaded on the board and soldered.  The first thing that I realized was  it was going to take forever sorting through the capacitors trying to find them.  I think I remember the step right before the installation of the first capacitor saying that all the capacitors should be sorted but who wants to do that..... :)  


The capacitors are not like the resistors.  The resistors come loaded on a tape in the order that they are used on the board.  Its a matter of verifying the color code, cutting the resistor off of the strip, and loading and soldering onto the board.


The capacitors came all mixed together.  The only capacitors that were not mixed together were the .01 uf and .001 uf .


Lots of really small capacitors!

Yes I spent 2 hours and 24 minutes tonight just sorting and taping the capacitors together.  First I was going to put the capacitors in zip loc bags.  After thinking about that I was going to use envelops.  Finally I decided that scotch tape would work and I would write the id number used in the manual on the tape.

Capacitors taped together


I am finally finished sorting them.  The biggest problem was with the small blue colored capacitors.  The ID number on them was in silver.   I had a hard time trying to identify them even under the lighted magnifying glass.  I would have to shade the capacitor just right to see the numbers on them.

Sunday, November 13, 2011

Elecraft K2 - Serial Number 007239 Build. Day 13

Hours 3:03:00    Total Build Time:   31:40:00     Nov 13, 2011


Started working on page 50 of the manual today.  The first item to build was the PLL (phased lock loop) upgrade.  The upgrade includes a thermistor that will keep the frequency more stable on the K2.

PLL Upgrade Kit


The PLL upgrade kit consisted of some wire, several resistors, a thermistor, and the circuit board.

Parts for the PLL Upgrade kit


Man these parts are small.  Most of the components of the PLL upgrade kit were 1/8 watt resistors.


View of the PLL upgrade kit


The PLL upgrade kit replaces on of the resistor packs RP3 on the RF board.  Wires were soldered onto the board so it could be soldered into place as RP3.

Completed PLL upgrade board


Once the PLL upgrade board was assembled, it was soldered into position at RP3.

PLL upgrade board soldered into position

PLL Upgrade board soldered into position


One of the many transistors soldered onto the RF board

View of the RF board

Varactor diodes added to RF board

Today I finished up on the second to the last step on page 51 of the manual.  Next time I start working on the project, I will be installing capacitors on the RF board.

Saturday, November 12, 2011

Elecraft K2 - Serial Number 007239 Build. Day 12

Hours 2:43:00    Total Build Time:   28:37:00     Nov 12, 2011


Work continued on the RF board.  All of the time was spent stuffing and soldering 1/4 watt resistors.


Soldering 1/4 watt resistors on the RF board

The lighted magnifying glass really helps when soldering the components onto the board.

Checking off components as they are installed on the RF board

I found the 'Annotate' mode in "Preview" when viewing a .pdf file.  I downloaded the K2 manual and errata sheet, made notes in the manual where there were changes from the errata sheet.  I check off each step in the manual after installing the part.   I like having the ability to also highlight, and add book marks.

Installing resistors on the RF board
Dang those parts are small.  The resistors in this case are not to hard to see.  There are some capacitors where the writing is so small that I even have a hard time identifying the part using the magnifying glass.


Installing resistors on the RF board


Resistor packs added to the RF board

Friday, November 11, 2011

Elecraft K2 - Serial Number 007239 Build. Day 11

Hours 3:15:00    Total Build Time:   25:54:00     Nov 11, 2011



Its been over 24 hours now on the build time and I have finally reached the step to turn on the K2 transceiver for the first initial power up test. This test will check the front panel, Control board, and the control chip and relays on the RF board. 



Well I was glad that the radio powered up with no problems the first time.  As I thought about it for a while, all it would take is one component in the wrong place or with the wrong polarity, or a cold solder joint or bridge somewhere....   Well, I just have to pay attention to each step and hope that the components are ok.


Its working!
After the initial power up, there where several other checks that needed to be completed.  First was the optical encoder test.  This test checked to see if the display was working correctly.  By pushing the rate button, I could verify that the display frequency changed correctly depending on the rate setting.

Next I tested to see if the 'band +' and 'band -' switches would cycle through all of the amateur radio bands.  As the band switches were pushed, the frequency display would change to the correct band and you could hear the relays clicking to accommodate the frequency.

I skipped over the section of the manual to construct an RF probe.  I decided that I would build that later when I needed it.

The next step was the construction of the 'Frequency Counter Probe'.  I found the parts and began construction.

Frequency Counter Probe
To test the probe, I had to enter the 'calibration' menu.  One of the menu items under the calibration section is the frequency counter.  With the Frequency counter activated, I tested the trimmer capacitor C22 which is just below U1.  It read 3999.98 hz which was within specs.

Next was the test of the CW keyed.  I connected my keyer to the radio and it worked correctly.  After that test the next test was setting the AGC threshold followed by the S-Meter alignment and 'Bargraph Current Test'.  No problems at all.  Each step was completed with no problems.  I ended the evening by dis-assembling the chassis back down to the bare RF board.   At that point, I started installing more resistors.  

Adding more components to the RF board


Currently I am on page 49 of the manual.  The next time that power is applied to the radio is on page 63 for the "Alignment and Test, Part II".  That will be at least another week worth of work.

Thursday, November 10, 2011

Elecraft K2 - Serial Number 007239 Build. Day 10

Hours 1:54:00    Total Build Time:   22:39:00    Nov 10, 2011


The missing part P1 for the RF board finally arrived today.  I was pleased with how quick Elecraft responded to my email about the missing part.  I sent the email first thing Monday morning, and the part was on its way First Class USPS that afternoon.
P1 RF board "Missing Part"

I finally received the part Thursday, 10 November, 2011 after ordering it on Monday.  Additionally I received a tracking number so I could follow the package.  Since I live in Hinckley, Utah, it was painful watching the part first arrive in Salt Lake City, Utah, then spend another day in Provo, Utah before finally arriving in Hinckley.


All required parts installed for initial power up test
Today I finished installing the rest of the components on the RF board that are required for the Initial power up test of the K2.  The components were "P1" and 4 ground jumper wires that are used for test points.


Case sides attached to RF board
Next the sides of the chassis were connected to the RF board.  After that the Face to the radio was plugged into the RF board and secured.

Sides, bottom, and face attached to RF board

RF board from rear of transceiver 

 The "Tilt Stand" was a pain to install.  What made it hard was installing the tilt bail while trying to install the screws for the second foot.  I didn't think that the tilt bail could be installed if the second foot was already secured to the bottom panel.

K2 assembled and ready for Initial Power up test
Finally the Control Board was plugged into the RF board, and then secured to the Front Panel board with 2 screws.

Control board installed
Well thats all for today.  Tomorrow is the "Alignment and Test, Part 1" starting on page 43 of the manual.  It is the initial power up (smoke test) of the K2 Transceiver.  Most of the circuits on the Control board and Front panel will be tested.

Hopefully the initial power up test will go ok.  All of the Inspections and Resistance checks on each circuit board looked ok.

Sunday, November 6, 2011

Elecraft K2 - Serial Number 007239 Build. Day 9

Hours 3:18:00    Total Build Time:   20:45:00    Nov 6, 2011


Continued working on the RF board.  I was able to get a lot of the parts installed leading up to the installation of P1.  looked all over the place and could not find this part.  P1 is used to connect the front panel board to the RF board.  


At this point I wondered if I could continue on.  Once P1 is installed, the next step is to install some ground jumpers, and U1 (PIC16F872 or 16F872A) which is the I/O controller.  After the I/O controller is inserted into its socket, several resistance checks can be performed.


I think that I will continue past the installation of P1, and add the ground jumpers,  Install U1, and also do the resistance checks.  I can then proceed with pages 39 up to page 42 where power is first applied to the unit.  After the resistance checks are made, the next couple of pages deals with the assembly of the case, etc.


When I receive P1, I can solder it onto the RF board and then perform the resistance checks again making sure that I didn't create any solder bridges.


RF board with all parts installed up to the step where P1 is soldered in

Audio headphone jack

RF Board

Power switch on the RF board

BNC connector for Antenna

CW key jack

Saturday, November 5, 2011

Elecraft K2 - Serial Number 007239 Build. Day 8 - Cont

Hours 1:28:00    Total Build Time:   17:27:00    Nov 5, 2011


Later in the afternoon I spent some more time working on the K2 Elecraft Receiver.  This afternoon I started out working on the RF board.  This is the main board of the Elecraft K2 transceiver.  The first steps in the manual was adding standoffs and 3 d attachment points for mounting the circuit board to the chassis.

RF board and parts

Below is a photo of the switching relays added to the board.  The switching relays were added to the board and 2 pins were soldered on each relay.  Each relay was then checked to see if it was inserted in the socket correctly and that it was sitting flush on the circuit board.


RF board with Band switching relays

Here is a closeup of the band switching relays.  There won't be to many more steps before the radio has enough circuitry installed that initial power on tests can be conducted.


Close up of band switching relays

Elecraft K2 - Serial Number 007239 Build. Day 8

Hours 1:08:00    Total Build Time:   15:59:00    Nov 5, 2011


Its a cold Saturday outside so its time to have fun inside working on the K2 Transceiver.

Shaft Encoder used for main tuning
 Assembly started today with soldering the 4 wires to connect the main tuning shaft encoder up to the Front Panel circuit board.  I am glad that I have a lighted magnifying glass to work under.

Installing control knobs
 Installed the control knobs on all of the potentiometers working left to right and top to bottom.


Installing main tuning control knob
 Next the Main Tuning control knob was installed, and that completes the assembly of the radio for this section.

The next section of the manual starts with the assembly of the RF board.

All knobs installed on front panel


Friday, November 4, 2011

Elecraft K2 - Serial Number 007239 Build. Day 7

Hours 2:00:00    Total Build Time:   14:51:00    Nov 4, 2011



Day 7 of building the Elecraft K2 transceiver.  The build today started on page 27 of the manual with the positioning and installation of the backlight assembly.   The first problem that I ran into is that I could not remember which polarity the Cathode and Anode were.  Sure I had electronics 30 years ago, but I have been working with computers (not with the hardware) for the last 20 years.  The manual did not mention the polarity of D2 and D3, and the PC board just had a + by one of the holes on each side.  Well its off to the internet to figure this one out.....


LCD Display backlight

Ok time to use the spacers to position the LCD backlight assembly.  The manual said to use some spacers.  Where were they?  I looked all over the place to find them.  I looked through all of the bags trying to find them.  I finally figured out that the LED backlight spacers were part of the Switch spacing tool.  On the third step on page 23 it talked about breaking the material away only at the four indicated points.  I missed that step.  Mystery was solved.

Spacers used to position LCD Display backlight

Front Panel board with LCD Display installed
 I ordered the SSB voice option with the radio.  At this point in the assembly of the Font Panel circuit board, the instructions called for adding the additional parts for the SSB option.  These parts consisted of 5 capacitors, a resistor, a resistor pack, transistor, and a plug which are all visible below in-between the 4 potentiometers.
SSB Option parts installed

LCD Display
 Dang it!  I melted part of one of the pushbuttons while soldering in one of the corners of the LCD display.  I soldered the for corners of the display and then went back and re-heated each of the corners pressing down on the LCD display.  This was done to make sure that the display laid flat against the backlight.

Melted corner of button cap with soldering iron

Top view of LCD display pins
Next was a visual inspection of the parts (polarity) and IC orientation to make sure they were installed correctly.  The solder joints on the bottom side of the board were checked for cold solder joints and bridges.  Everything looks good at this point. 


Well we are finally looking like we are getting somewhere.  Below is a shot of the front panel with the green filter for the S meter and the clear LCD bezel.

Elecraft K2 Front panel
Again at this point in the assembly process, there were 60 different resistance checks to perform.  The checks passed with no shorts or un-usual readings.   Good!