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Ham Radio

SS-40 enclosed

[yesterday: 3.5 miles]

This past weekend I tackled the enclosure part of my SS-40 kit (SS-40HT receiver plus SS-40TX transmitter) from 4-State QRP Group.  I have had the completed radio sitting here for quite awhile, building up my courage to cut the aluminum extrusion case to the proper length.

On Sunday I dug out the table saw and ran a piece of aluminum scrap through it.  It cut pretty good with the regular blade.  So I carefully set the fence to the right position and cut the upper and lower parts of the clam shell extrusion.  Using a cardboard dummy faceplate to help me locate the pass-throughs on the front panel, I layed out and drilled it.  I had a little bit of fudging to do but nothing extravagant.   Then I had to do similarly to the back plate and use the mounting screws to carefully “tap” the aluminum screw holes.

There are two general ways of wiring the controls of a thing like this.  One way is to use control elements that are separate from the circuit board and put wires from the board to each control element.  This kit uses “board mount” controls which are soldered straight to the board.  The board mount controls mean that the locations of the holes in the face plate need to match with the fixed position of the control elements.  Since my equipment/experience/ability are weaker in the mechanical parts of the project, like drilling holes in an accurate position, I find the board mount controls to be harder to manage.  But I think it turned out OK this time, more or less.

I had these rub on letters (T – tuning; V – volume; P – headPhones; K – morse code key).  I think I would like some smaller letters better for style, but these will work for now.

And I had these blue knobs saved from an old project.  I really like the blue knobs.

A couple of things I don’t like.  I don’t like the antenna jack on the front.  With the headphones and key attached, and the BNC antenna feedline, it gets a bit difficult to use the knobs; things are just a bit crowded.   A 90 degree BNC connector would help.  I think I have one of those around here someplace.

And I find the volume gain a little strange.  I don’t  hear much of anything on the lower half of the V knob but only on the upper half.  That may be a legitimate result of a low noise design; maybe I’m turning it up too far just to hear the background noise.

I don’t have any kind of a tuning indicator yet.  I may get some smaller stick-on letters/numbers and put a few around the ‘T’ knob for rough indication.