by Arky (TheRPF member)
THE MkIX/X VARIANT, TR-595E
It has been years since I visited the Forums and it is like visiting a new place but with the same location. While I was searching for updated information on the MkVII Tricorder, there was one thread which got my attention. TheRPF Forum member, Arky has created a new Tricorder. His version, the TR-595E is the evolved variant of the MkIX or MkX. With the help of MangyDog (the creator of the unused Voyage Tricorder concept), his Tricorder has an animated LCD screen. All this was created from Fusion360.
Arky (aka ArkysLab) or better known as Mr. Nicolas Duchette, has uploaded all his files into his Github Repository. You can download the Files and make your own working TR-595E. But there is one section which has not been done; sound.
FUSION360
Reading his thread, I was actually amazed and learned a few things. One of them was how Fusion360 helped him to bring his concept to reality within a very short time. From 3D printing to PCB design. To be honest, the subscription fee is quite reasonable but not from where I am. The currency exchange is about 4.4 times. I had to reconsider since this is still a Hobby.
The vertical bar on the lower flap is cause for concern. At this point, I surmised it is to help hold up the PCB but, if I were to redesign the circuit board, it could be a hindrance. Luckily, the STL files did not have this bar.
Arky has kindly shared his work via GitHub, a place which I have heard before. After becoming a member, I could not grasp the concept of ‘Forking’ and therefore, I email him my modified files instead.
THE GITHUB FORKING OR MY INTENTION TO MODIFY
The MkIX or MkX as seen in Star Trek Deep Space 9 and Voyager was the next model up from the MkVII, which started from the Third Season onwards of Star Trek The Next Generation.
In the Repository, I think the circuit diagrams can only be accessed if you have Fusion360. After importing the Gerber PCB files into the EaglePCB, to my delight, I realised the circuit actually uses the 555 and 4017 ICs and it was configured as a 4-step sequence. Originally, my theory in the late 90’s was that the same circuit were used on most of the props. Eventually, my theory was more or less confirmed with the emerging of the Internet.
With that revelation and with the Gerber PCB information downloaded, I can actually create or modify the original circuit. The crucial information I needed was the placement or positions of the SMD LEDs coincides with the 3D Tricorder casing’s holes.
THE 555/4071 COMBO
The 4017 CMOS chip lights up 10 LEDs or Lamps one by one, in a sequence, depending on the (shape of) clock pulse from the 555 timer IC. Changing the values of the capacitors and resistors on the 555 IC will determine how long the LED will stay lit. And re-wiring the 4017 allows you to set the LED sequence to any steps below 10. In most TNG Star Trek shows, LEDs in most props have a 4-step sequence.
THE FRONT SENSOR
The front sensor array with sweeping green LEDs is one distinctive feature of the Tricorder. The MkIX/ X on the other hand, has two rows of scanning LEDs. For years, I did not notice the upper green LEDs on my eFX replica, only its bottom scanner was amber. I have also seen Red or Blue LED variants too, with the latter being the MkX Medical.
In Arky’s PCB design, I was surprised that there were two pairs of 555-4017 ICs. In my mind all these while, I thought the actual prop was using a single 4017 with 8 outputs, divided between the two rows of scanning LEDs. The eFX replica soon dispel that theory because the two scanning LEDs were sweeping on different speeds.
THE TOP PANEL PCB
This was the section where I started to first dabble with Arky’s original PCB design. In the original MkIX and MkX, the upper right panel has an animated LED sequence. It sweeps from left to right repeatedly and I wanted to have that feature again. After I recreated the Circuit board and emailed to Arky, I realised that the new LEDs might affect his Tricorder casing. So, I would need to find someone who can 3D print his files so I can use it as reference for testing the modified circuit boards.
It is a very simple circuit to direct drive 7 LEDs.
Also, there is a jumper when you need to solder to select the 4017’s clock pulse. You can either use the clock pulse from the 555 next to it or, solder a wire from the jumper to the FRONT ARRAY PCB’s 555 IC.
THE POWER SUPPLY
After checking his three PCB designs and going through the PARTS_LIST.XLSX file, Arky’s Tricorder is powered from a single 3.7volt LiPo battery. At first I thought everything was running at 5volts with the assistance of the Qi Wireless Receiver. My reasoning was based on the calculations on the LED’s current limiting resistors. But when I confirmed it with Nicholas Duchette, the whole system was running on 3.7volts with the LEDs lit at 10mA and not 20mA which I so wrongly assumed.
THE LOWER INTERFACE
In place of the four green function lights (ALPHA, DELTA, GAMMA & DELTA), there is now, a 2.2″ (320×240) TFT LCD. The four green functions has been relocated to the bottom flap aka LOWER INTERFACE.
Once I have the opportunity to get the part 3D printed, I can see the need to modify the PCB. I want to light up the ID section and also, put in the GEO, MET and BIO buttons. And maybe, even allow it to make beeping sounds when the ‘controls’ are touched.
SOME TECHNICAL CONSIDERATION
Section 10.6 of the Star Trek the Next Generation Technical Manual states that the 8.5 x 12 x 3cm MkVII Tricorder weighs in at 353g. This micromilled duranium foam construct is almost as heavy as two Huawei P10 Plus mobile phones. My eFX MkIX is even heavier at 468g, which is like carrying part of a brick.
I guess that when the TR-595E Tricorder is completed, the weight could be very less than the two numbers above. Just for some real World comparison, my Huawei P10 Plus (165g) and a Samsung Galaxy J2 Pro (82.3g) combined is just about 237g and it already has quite some heft.
If you are interested in this Project, you can start to follow Arky’s thread in TheRPF which will lead you to his GitHub page. You bet I am going to re-create his Tricorder and I might want to change things a little as I go along.
