Thursday, October 1, 2015

SNA jr Re-build Updated 11/9/2015

There is a upcoming 'Makers Fair' in Atlanta, and several of the local Ham Radio clubs are going to have a display there.  They will demo some equipment and modes of operation. There will also be  several hand's on activities for the attendees. 
I decided to rebuild the SNA Jr. as part of the exhibit. I redesigned the circuit board, making it a little larger to make it easier to build.  Being larger it will no longer fit in the Altoids tin, but I found a metal Crayola Crayon box that was the right size.
 
I also found a nice small 12 V battery pack with charger on e-bay, they are available in several amp hour ratings.  It is just the right size to fit under the circuit board.  It has a built in On/Off switch and  a separate cable with the charging connector, which makes it very easy to build into projects that are battery powered.

Since this will be a show and tell event, I needed to make it "pretty".  Cutting the required holes in the lid of the tin, caused the metal to deform around the cuts. To make it smooth and sturdier, I glued a piece of .020" circuit board material on top of the lid, and filled in around the edges with some auto body filler. After a paint job, I applied some laser printed decals for labels. I also printed a fake bezel to put around the LCD display.

Along with the new circuit board, I also made a new RLB board that will connect directly to the SNA instead of having to use cables.


Here is a picture of the finished unit with the attached RLB.
It shows a normalized scan of my 80-40 meter  dual band dipole antenna.  Using a RL-SWR table lookup, the  SWR values are the same as when I scan the antenna with my FoxDelta Antenna Analyzer.


I have placed all files  necessary for building
including Eagle files and toner transfer image 
 in the following dropbox 
https://www.dropbox.com/sh/16bxycnl2xg7vqi/AADcMnY9LNpBBfRuFJkzlVD-a?dl=0 
 






4 comments:

  1. That looks really nice DuWayne. Well done indeed.
    72/3
    Tony G4WIF

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  2. Beautiful job DuWayne. Professional!!

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  3. This comment has been removed by the author.

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  4. Beautiful project.
    Can you please post the updated schematics (higher resolution display) and firmware?
    What is the part number of the display?
    Thanks,
    Victor - 4Z4ME

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