Construction of the MKARS80 Transceiver continues with the installation of the bag #4 components.  This bag contained all of the active devices, as well as the crystals for the BFO and filter.

As these were just dropped into the holes, I didn’t take a lot of pictures during this phase.  Here is the board after all of bag #4 has been populated:

Board with Bag 4 parts installed

Bag #5 contained the PIC chip, LCD display, controls and variable capacitor.  I could not get the polyvaricon leads to fit into the holes on the board, and ended up trimming them thinner.  At first I tried my side cutters, but they are getting a little dull.  In the end, I used some toenail clippers!  After trimming, the leads fit through the holes OK.

Polyvaricon variable cap with leads being trimmed.

Here is the component side with all of the bag #5 components installed (except the display and PIC chip).

Bag 5 components installed

And here is the back of the board, with the controls poking through…

Trace side of board after bag #5

At this point, it was time to do the preliminary checks.  The initial resistance check (12 volt input to ground) measured 1.9 K.  Both 5 volt and 8 volt supplies were within a tenth of a volt of specifications.  Next, I plugged in the pic chip and installed the LCD display. Application of 12 volts showed no smoke, and a faint hiss was heard in the speaker.  Upon attaching an antenna, I heard and noise, and the normal interference I hear on 80 meters from the Plasma TV in the next room.

It’s important that the LCD does not stick up too high, so I installed a couple of the standoffs, and ran a straightedge across them and the LCD display.  This way I could make sure that it didn’t stick up above the standoffs.

Mechancal alignment of LCD display

Pins were soldered into place, and everything was set.  I turned the set back on, and two bars of blocks appeared where characters should be on the display.  A simple tweak of R29 (contrast control) made normal characters appear.

LCD Display working

It was a little out of band, so I adjusted C38 to bring it down some.  In the end, I couldn’t get quite the whole 500 khz of range, but I’m thinking I would like to install the 10-turn pot/varicap modification anyway later.  But I want to see how it works first.

It was still daytime, so no activity on 80 meters at this point.  I’ll hook it up to a frequency counter to adjust the BFO tomorrow, and see how it sounds.