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| SVTrackR SMD TNC |
In my learning process of making my own DIY PCB and after ordering some common SMD components ( capacitors, LEDs &, resistors ), I decided to design a small and functional TNC that only need 4 connections to handy and a few jumper wires to Arduino.
*** This is the first time I ever successfully made a DIY PCB.
Let's start with the design on EagleCAD ..
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| EagleCAD SVTrackR SMD |
I designed this small 28x23mm board for fun and to learn on how to solder SMD parts on DIY PCB. I made everything on a single layer. The only drawback is the two red and green LEDs are at the bottom where the copper traces are located.
Generate gerber and do a 3D view of the board. This method is easier to spot any errors.
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| 3D Gerber view |
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| Printed out for UV transfer to UV PCB |
This is the tracing paper before the UV treatment. Thanks to Uncle Chow, 9M2CF made me a nice photo frame to hold the UV sensitive PCB and tracing circuit in place.
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| PCB holder / cover |
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| UV lightbox |
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| UV lightbox UV LED turned on |
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| UV lightbox and photoframe cover |
After like 15mins ( long duration was due to the diffused and evenly distributed UV light ), I drop the PCB into sodium hydroxide 0.7%. This is removed whatever parts exposed to the UV light and leaving the green part for second steps.
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| Exposed copper after Sodium Hydroxide bath |
Once the Sodium Hydroxide bath was done, I wash it and dump into the second solution - Ferric Chloride to eat away all those exposed copper.
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| Ferric Chloride bath |
After a few shakes and turns, all the copper were wash away leaving the green portion of the copper traces.
I use thinner to clean away the green stuff and leave you with a shiny copper traces. Not bad for a first timer doing SMD PCB.
Now for the drilling and soldering part. A tip from 9M2CF, always solder before drilling as the solder will guide the drill bit into the holes to be drilled.
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| Drilling holes |
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| Soldering SMD resistors |
With too much solder at the pads, those SMD 1206 resistors are uneven on top ... or I was using a really fat tip.
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| SMD SVTrackR TNC back |
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| SMD SVTrackR TNC front |
After a while, got all the SMD and through-hole parts soldered. Need to find the SMD parts for the 100K POT. This is the one I currently have in my part inventory.
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| Add caption |
Comparing sizes between the old MicroModem with Mini Pro and the new SMD TNC that will run from either Arduino Mini Pro or Arduino Nano.
