Category Archive Computers, Servers & Net

ByJohn Wuethrich

Car key transponder/rfid fried by proximity to inverter welder?

I havent Confirmed beyond reasonable doubt that the harborfreight titanium 125 is the reason my ford fusion 2007 was rejecting the only key I had at the time. Rejecting as in not accepting What is usually called a chip or a transponder.

The actual name for the chip is a DST tag and its made by Texas instruments. It operates at 134mhz and outside the car world would be refered to as an RFID tag/chip rather than a transponder


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ByJohn Wuethrich

Raspberry Pi NFC

In 2015 I was working on an idea with linux and nfc. heres a bit of messing around with a reader that was less than trivial at the time to get working.

ByJohn Wuethrich

Clearlinux KVM Host Nvidia graphics(PCI-E) pass-through

40 inch beaver (ubuntu 18.04)

here you see a 40 inch beaver in 4k (phrases not to google at work or at all(40in)) It wasnt perfectly straigt forward but I eventually managed to get Intel’s ClearLinux (playing hypervisor/kvm host) to let Ubuntu 18.04 take an nvidia 1650 with out the ACS override patch. 

This article is a work in progress but im going to try to put some roughly formatted things that worked for me before i worry about making it pretty

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ByJohn Wuethrich

Lithium Ion Pack Spot Welder

This is a write up on an early but working design for a CD Spot Welder. Its fet switched and electrically isolated with intent of actually being able to control all electric fab processes. The weld energy comes from a bank of Maxwell super capacitors. 

I needed a large quality lithium ion pack. Part of that is high quality cells properly joined (a bms being the other liability/safety component). China cells or packs featuring cells with fire right in the name seemed like too much truth in advertising and american made either comes with limitations like requiring complicated battery auth with bms or $. So I decided on assemble your own from sourced cells. This isnt meant to be a post on pack construction though. I will probably publish one at some point because a lot of the YouTube community and especially ebike community scares me speechless when it comes to litium ion pack construction.

Lithium Ion Pack Spot Welder 1
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ByJohn Wuethrich

Fabing PCBs w/Custom Made UV Lithography Rig

One mans advernture into emulating industry standard pcb etching processies at home:

Why and how did I end up wanting to make boards?

For years I have done small business and residential I.T consulting. I stopped counting for client pc/workstation builds at 30 maybe 10 years ago. I had an internship with a university where I managed their MS Dynamics Teaching Lab and had converted it from 10 optiplex to 3 rack servers with hyper-v in 09-10ish. I started CS and went MIS then IS (changing universities) and somewhere in between I wanted to learn more about the CE/EE side of how code runs on the actual hardware.

over the years I slowly accumulated bits of that knowledge. probably starting at age 12 or 13 when I passed the Technician class Ham radio license exam.

One day I got the urge to bring to life a few hardware ideas I had. I decided that because i have no formal pcb design edu but had a stack of plexi left by old roommate…. being able to rapidly prototype would be essential to cost effectively learning pcb design and possibly developing products.

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ByJohn Wuethrich

Routed Static Block With PPPoE & OPNsense

Centurylink PPPoE, Routed Static block & OPNsense

Routed Static Block With PPPoE & OPNsense 2
Yes motherland non soviat bandograph meter u in skew

If you are just getting started with Opnsense or first time with a static block This post is for you! When trying to figure this out a lot of form posts said it couldn’t be done this way and to use 1:1 NAT; so maybe even those around the block a few times will benefit. 

This post is a somewhat how-to for setting up a static block with routing on opnsense over pppoe with a modem in transparent bridge mode.(vdsl2 & centurylink) This Assumes you want to end up with a NATed DHCP Private LAN and a DHCP Public ipv4 routed LAN. Buckle in!

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