Monday, October 31, 2016

BITX 40 v 3

I have been gone for a while visiting family, and have not had a chance to work on the projects I have on the bench.  One of these is a SMD version of the BITX 40, that was only available in India.  Just before I left, I saw that a newer SMD version was available for sale world wide.  And, at only $45.00 including shipping I decided to order one.  A couple of days after I returned home, I received a little box from India.  Inside was a very nice assembled SMD BITX board, and a bag of components needed to build a working transceiver.  Since the local QRP club was going to have a table at a hamfest next week, I decided to quickly build this up for something to display.
I want to make a few minor changes to the kit, first I wanted to use a 10 turn pot instead of the one included in the kit.  Along with that I will add one of the re-packaged DL4YHF counters I designed a couple years ago. I also will use an external hand microphone with PTT instead of the electroet mic. that came with the kit. 

 Next was to come with a case to put it in.  This is exactly what I bought the 3D printer for.  I printed some 6" corner pieces I had designed right after I got the printer, and cut up some double sided circuit board material to use for the sides of the case. I have switched to using .032" PCB material for chassis panels. It is very easy to cut accurate size pieces with a simple paper cutter. The back panel is very simple just two mounting holes for the power and RF connector, and 4 screw holes for mounting the panel.

The front was a little more difficult.  I needed mounting holes for the tuning pot, volume control,a separate power switch, along with a hole for the display. I also decided to add a grill opening for a small speaker to mount behind the front panel.  I went with a panel .2" thick to give room to build in a bezel for the display, and allow enough depth to add a recess to hold the 7 segment display for the counter.
After a couple hours to lay out the design and a few more to do the printing I came up with a very nice looking case for the project. I cleaned up the printed parts, assembled the top and bottom of the case, and gave everything a coat of paint.

 Now to put everything together tomorrow, and see how it works.


  1. Would you like to make up an extra case for sale ? What would you charge ?
    Tks and 73 Ralph K1KOB

    1. I do not want to get into the cabinet business. when everything is done I will post the 3D print .stl files so others can get them printed if they have a printer or use one of the companies that will do prints.

  2. Could I please have the .stl files?


  3. Still making some changes to the front panel, but I put the rear panel and corner pieces .stl files for cabinet in
    Will add Front panel when everything is finalized.

  4. Have you gotten the front panel tweaked in yet?

    de KC8MWG

      has what I ended up building. It is specific to the VFO board with display I built. An easy front and rear panel for the case built from pcb material and printed corner pieces can be made from .060" PCB material. Fairy easy to work with. If you want i can send the .stl files and you can take a look at them