Category Archive Printed Circuit Boards & Custom Electronics

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

Vacuum Pull Down Uv Lithography Rig

Vacuum Pull Down Uv Lithography Rig 1
Vacuum Pull Down Uv Lithography Rig 2
In the Gap Above the pvc a celing can light bracket allowed positioning forward back up and down
4.1w uv led
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 3
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