So my wife's surgery went well and she is recovering. I wanted to share a story about a fellow Fallout fan encounter at the Hospital. So there I was waiting for them to call and tell me I could visit my wife in the ICU. When I noticed a Vault Dwellers Survival Guide book across the room. I walked over and found a fellow Fallout 4 fan, also waiting for his wife. I told him what I was building, and about this website. He thought it was all very cool. He loves the game so far, but misunderstood the start of the game and thought that you first played as the mother and then at some point would switch to the father. He was on a xBox so no console commands would help. In either case we chatted for a bit about what we liked about the game. He said I should design some power armor, I told him that there were already people on it, here at the RPF. It was a nice respite in an otherwise already exhausting weekend.
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Project update:
Before I headed to the hospital I designed the custom circuit for the holotape. It will allow the holotapes to actually transmit optical data! Not any real audio or text, but at least transmit a unique ID. The circuit will still use a tiny number of inexpensive components. It could be built by hand, but I plan on doing a small run of PCBs once I get it working on a breadboard.
he cool part is that you will be able to change the unique ID of the holotape on the fly simply by rotating the the gray spindle. 12 unique IDs will be made possible with a detent stop on each. However, since the in-game design of the holotape has no markings on the spindle it would be difficult to tell which one you selected. So there will be tick marks into the bottom side of the spindle, the marks could be uniquely colored with a pen, or left alone.
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The circuit for the Holotape uses a dual 555 timer chip (556), This chip is one of the workhorses of the electronics industry and if you studied electronics,it is one of the first chips you probably ever made anything with.
Here is how the circuit works, starting at the left:
First is a battery for power. Then a cutoff circuit. A PNP transistor blocks all power to the rest of the circuit when the OFF switch is closed. (Why didn't I just use a normally closed sensor switch? They don't make them this tiny.) The switch is a tiny plunger sensor that will be activated anytime the sliding door is closed. So now the holotape only works when the sliding door is opened.
C3 is a bulk capacitor, there to smooth out the battery power, useful since the rest of the circuit is a repeating on/off signal.
The left side of IC1 is a simple 555 timer timer circuit. It creates a repeating digital pulse that is anywhere from 650 to 970ms in length. The potentiometer (RV1) is a variable resistor. By turning the spindle you can alter the timing of the pulse. The spindle will have 12 detents built into the 3D print. This will stop the resistor on 12 possible unique values. Why 12? Well you can only 3D print so small of a detent and have it function properly, and there will be some variation in the actual stopping point of the potentiometer, so by using 12 positions, I gain a 26ms margin of error when detecting the signal. The cool part is you can change the tape ID on the fly.
The right side of the circuit is a 38Khz Modulator. This basically can take in a digital 1 or 0 signal and then puts it onto a 38Khz carrier wave. The carrier wave ensures that the signal can be detected remotely without other signals interfering. This modulated signal is sent out using the red LED. This is actually how your standard IR TV remote works. To receive the signal I use a standard, low cost 38Khz IR remote receiver chip. You will find one of these inside anything controlled with a IR remote. They can be easily connected to a microcontroller.
To detect the unique ID I will be using the "PulseIn" feature built into the Arduino side of the Udoo Neo. This measures the width of any incoming pulse. Read the pulse width, and translate that width into a command and vola! You get a functional holotape that actually uses optical data transmission.
The cost of the circuit should be around $7 + PCB costs (I have yet to make a complete BOM.) The 3D printed portion comes out to $23 on shapeways. The cool part is they can dye the orange part. The white, grey and cream parts would have to be dyed afterwards.
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Here is a little Fallout error:
I noticed while designing the holotape that the lone survivor actually puts the holotape into the Pip-Boy up-side down!. At least up side down as compared to the way the tapes show up when placed on a table, or examined in your inventory. (I am using the printed side of the game holotapes as a "top")
