With 3D printing some old bugaboos are soon dispelled with delivering a high quality finished looking project. I don't have a 3D printer, but some blog readers do. Just like I have a CNC, but most hams do not.
So where is this going -- well sometimes all you have is an old shoe and how do you turn what looks like crap into a nice-looking rig suitable for display on your operating desk. That is our journey for today. Lots of photos so you don't have to read much.
The Simple SSB Transceiver came about when I asked myself about how I would design a new rig that was not a warmed over Bitx. Not that there is anything wrong with a Bitx -- it is just I wanted my imprint on the design and the challenge to do it using only 10 devices. I was successful and later on that same challenge to myself was to do it with only 7 devices. That challenge was successful and resulted in the P3ST.
The Simple SSB Transceiver
At this point I should note that the Simple SSB Transceiver was taken up as a Club Project by The Vienna Wireless Society where some 15 units were fabricated. [Now for a bit of irony and a twist of fate. One of the VWS Club members who built this project initially started by building a prototype set of boards. Recently he took those boards and replaced the 9MHz Filter with a homebrew 45MHz, 28kHz wide filter. Then using those prototype boards, he successfully homebrewed a copy of the SBitx, a SDR version of the Bitx. Indeed, a twist of fate.]
But what was not previously divulged was that the actual rig was built from a bunch of "old shoes" (a metaphor). Basically, I used what I had in the junk box and from the scrap pile. This also presented some technical challenges beyond the circuits.
My opinion, but I think the front panel looks pretty cool with the 16X4 Green LCD and the yellow background panel. The ergonomics of my Fat Fingers have been addressed in that the main knob is easily gripped without bumping into other controls.
I could lead you into thinking this was all by design that required many hours of noodling. Well, the truth is that the front panel was formerly the front panel (cut down) of the 30M CW transceiver previously shown on this blog. (I hated that project.)
The move to the 16X4 LCD was to cover over (by cutting out) some former holes. While I was at it, I added a 2nd VFO to the sketch as I needed something to fill the LCD Screen.
Above is the bare front panel and two of the former holes in the panel needed a fill. In the lower right-hand corner, one hole became the home for audio phone jack and the hole to the right of the Microphone jack was filled with a 4-40 bolt and nut --it serves no purpose other than to fill a hole.
An attempt to conserve valuable space behind the panel resulted in mounting the digital electronics behind the LCD. 6-32 aluminum spacers fitted to the LCD mounting holes provided 4 mounting points for a sub-panel to contain the Arduino Uno and Si5351. This conserved a huge amount of horizontal space behind the front panel.
The Plessy Module with ADE-1's
Several Small Assemblies vertically mounted on Angle Stock
Unknown at the time, the above three circuits represented a technical challenge and later I will describe the simple fix. Note the BPF on the right.
The Back Panel ~ Scrap metal from a former rig!
The sides were made from galvanized flashing ~ Home Depot.
To provide a rigid mounting for the front panel I made triangular shaped side panels and the hypotenuse side was "hemmed over" to add stiffness. This galvanized metal about the size of a sheet of paper cost about $1 a sheet at Home Depot and is easily cut with Tin Snips and bent in a vise.
Now to the resolution of the technical problem. If you look in the photo above, you will see a remnant of a price sticker (small piece of sticky paper) on the galvanized metal. Right behind that is the band pass filter seen in an earlier photo with the small three circuit boards.
When you put the left side panel on the assembly the BPF coils were so close to the galvanized steel that they became de-tuned. Since the board was vertical -- no way to tune the trimmers. About a minute of thought and a return to a "tool of old". I have a set of Greenlee Chassis punches including one that is 1.25 inches in diameter. Boom I cut a perfect round hole in the side panel and now with that hole could have access to the trimmers. Simple solution!
The Driver and Final Boards Fill the Back Panel.
Just to round things out, the Microphone amp and the Audio amp were small circuit boards vertically mounted on a piece of angle stock along the right side of the main Plessey board.
I can say with certainty there were a lot of old shoes used in the project but if you look at the front panel you would never know that much of the physical construction aside from the electronics was nothing but recycled and repurposed stuff.
Hopefully there was some tribal knowledge tips of use to the blog readers.
73's
Pete N6QW