In my last post I described the ESP8226 based LOGIC board I am using for processing the data from my Geiger telescope. Today I finally got around to cutting and putting this board together.
Hopefully this will be the last PCB I need to cut for the 4 tube prototype. The board design is quite simple. The whole detector will run if a 9V battery or an optional AC adapter. 9V is regulated to 5V via a nameless 7805 DCDC replacement. There is a header for logic level signals from the HV_DISTRIBUTION board, and a couple of output headers. One of the headers has a rudimentary low pass filter, in case I decide to generate audio with the ESP8266. I am curious to see if the unmilled copper underneath the WIFI antenna is going to compromise the signal quality. I will keep an eye on it, and if it becomes a problem a rotary tool will make a quick work of it.
First stab at mechanical design.
Mechanical design for this project will be as simple as possible. The only portion I will be cutting on my CNC router will be Geiger tube holder. The rest of the contraption is constructed out of acrylic sheet and nylon spacer. Below is what I got so far.
This got me thinking. Instead of adding more channels why not rotate my 4 tube contraption around the center axis. If I have feedback of the detector angle, perhaps with a angular encoder, I can cover far more angular positions. The only problem with this plan is finding a slip ring to pass the ~400V dc to the tubes. Perhaps the rotational portion can include the HV components and only the logic level signals will be passing through the slip ring? Just some food for thought.
Next up mounting the LOGIC PCB and cutting the tube holders.