I got so excited with this Tricorder Project all because of this very PCB. Mr. Douchette’s original design calls for direct driven LEDs. In other words, the LEDs just lights up and does not sequence. After poring over his original files, I added a 555/4017 circuit as the PCB has enough space.
I also designed the PCB to have only the LEDs at the component side (ie top side) of the board, which means. I can now have the PCB mounted flat. The LEDs will protrude out from the Main Body’s has windows. Also, the re-design allowed me to test out one feature which escaped me for years, which is to reverse solder have normal SMD LEDs.
Just for fun, I will include the option to select clock source either from the on-board 555 or, you can tap the pulse from the Front Array PCB. But you will have to be good with a soldering iron though.
However, while I was soldering the PCB, it needed some revisions and also, the board has a weird error which took me the whole night to troubleshoot. Details are in this Blog Post.
THE ARKYSLAB TOP PANEL DESIGN
The original PCB has the seven Amber SMD LEDs light up all the time. This is great because the board is very simple and you can make a quick job soldering all the components. When you mount the board inside the Main Body, the SMD resistors would create a slight gap. Add in the thickness of the main body, the gap is extended and so, when you put in the diffuser or Mylar, the lighting effect is nice.
THE RE-DESIGNED PCB
I still want the Tricorder to have the four sequencing LEDs at the top right panel. Using the Gerber information from Mr. Nicholas Duchette’s PCB files, I re-created an alternative version. I replaced the two LED Amber LEDs, with four yellow LEDs and put in the 555/4017 circuit to animate them. There is a design consideration not to add the 555 IC but to tap the signal from the Array Board. I let the User decide how this board can get its clock pulse for the four LEDs by using a soldering iron. So, if you need to tap from the Front Array PCB, you just solder the link at the jumper. I solder the link to the 555 IC by default.
Another modification is that I wanted the power indicator to be a full solid green. If you use a diffuser, you will still be able to see the hotspots of the two SMD LEDs. I design this board with the intention of it being the distribution point of power. There would be some connectors for a fourth PCB to piggyback onto so that the TR-595E can have some sound.
This board is also another milestone for me because after so many years, I am able to reverse solder SMD LEDs and use their lighting effect. This lets me mount the PCB directly into the inner walls of the Main Body without any gap. I did this by putting all components at the Solder side (ie Bottom Layer) of the board.
THE RE-DESIGNED TOP PANEL PCB VIDEO
THE REED SWITCH
The Tricorder will be activated by opening its flap and there is no visible switch for you to interact with. In actual fact, these Tricorders uses two types of reed switches; Normally Closed (when opening the flap) and Normally Open (when about to close the flap). The former is to power all the PCBs within while the latter is to enable the closing ratchet sound. For the Normally closed reed switch, it is soldered to the Top Panel PCB and you can get more information from the Blog post.
TESTING THE NC REED SWITCH VIDEO
The other function of this board is that it distributes and control the power to the Tricorder with the use of the NC reed switch. And right now, I am designing and testing a piggyback system where a fourth board will provide sound to the unit. After soldering the PCB, I need to revise the design again to make some changes. One of them would be to change the PCB to PCB connectors which are of the wrong size, plus I have not decided on which sound system to use.
20220902 Top Panel PCB v3 (Improvement 2)
This is the third revision of the Top Panel PCB. It is the same as the V2 but with some changes. It should be the last revision and I plan to have a look at the Front Array PCB again.
