Marksmann GPS

[dstone]

Since I've been working some odd schedules at the office due to designing and building a new TV studio I decided to pick up a little side project I could work on at night. I got inspired by Rymo's Marksmann GPS build over on the RPF and ordered a few on eBay with the intent of keeping one for my video production systems and giving the others the GPS treatment. Only one in the group worked, so I'll probably just wind up modding them all. The cases are scarred up pretty good where somebody tried to grind out the CSPAN engraving and have lots of little dings from being tossed around in a TV truck for years.

The one that works will be modified similar to how Rymo did his, reutilizing the integrated screen and running everything off a Pi Zero.



My other units unfortunately do not function at all, so their guts are not really useable. It seems to be near impossible to find 5-inch 4:3 LCDs anymore but I did find a 4.3-inch 16:9 screen specifically for the Raspberry Pi system that fit well. I had a spare RPi 4 I was able to use and found that it fit in the space made available by removing the original LCD screen. I trimmed the Tektronix circuit board a bit with my Dremel and used the standoffs included with the RPi LCD to hold everything in place. I still need to mod the original power switch to start and cleanly shut down the RPi.





I have some VHF antennas and PCMCIA cards on their way. The gold-on-black labeling tape arrived over the weekend. Will probably have to 3D print the sun hood as even generic 5-inch 4:3 hoods seem to be rather hard to find now. And the stupid supply chain issues have Raspberry Pi's impossible to find, so that essentially brings the electronics side of the project to a halt for the moment.

[dstone]

Got lucky and landed a few Raspberry Pi Zero 2 W units and moved my RPi 4 over to a home automation project. Had to swap out the display with a HDMI model since the Zero 2 doesn't have a DSI connector. Ordered some DC-DC buck converters for power.

The PCMCIA cards have arrived and I'll start cutting those down shortly. I'm a bit aggravated with the VHF antennas, I'm thinking the seller I ordered from has drop-shipped them from China. Hopefully they'll be here in a few more weeks.



I tweaked up the Pi software so it loads pretty seamlessly into the video now. Also made a boot screen image modeled after the one Rymo made on his build.





The Marksmann logo looks a bit lumpy due to the engraving being ground off the faceplate. Not very noticeable in person. I might tinker with distressing one to look like it was found after the dino rampage.

[JP Junkie]

This looks great. I began mine a few years and stopped. I got frustrated with the wiring and soldering of the small parts and put it on pause.

How is the non-factory screen setup working for you? I was thinking of something similar, but I have a working unit, I would wait to buy a broken one.

[dstone]

The screen fit great but I ran into a problem with the video playback software that wouldn't properly scale to fill the screen after I moved some stuff around. I haven't had time to sit down again with it due to my crappy work schedule. Once I'm able to sit down with them again I should be able to get four units with the Pi screen and two with the OEM screen done. I want to try to at least have one done by the end of July to display at a local convention.

[JP Junkie]

Oh wow, 4 devices. Nice! I look forward to seeing these completed when you get the chance!