Growing Thermal Silicon Dioxide on Silicon Wafer

I had the day off school due to a bomb threat so I had some extra time to work in the shop and had my first success with thermally grown SiO2. The process is very simple. At the time, I didn’t have a tube furnace so I put the wafers in a pottery kiln that went up to 1000c and poured 25ml of water into the top of the kiln through a small opening manually every 5 minutes for about 6 hours to saturate the furnace with water vapor. This wet oxidation technique allowed me to grow the field oxide for my first few semiconductor devices, diodes.

DIY Doppler Radar – LNB Hack

I modified a satellite LNB to transmit as well as receive on 10ghz and connected the downconverted and mixed signal to my scope. I can use it to measure doppler shift and therefore speed of a moving object. I did the modifications by removing HEMT RF FETs and rotating them so their gate is where their drain was and vice versa. The source connections stayed grounded. I then had to cut some of the traces on the board and change a few resistors and things to make the biasing circuity work in reverse. I then capacitively coupled the dielectric resonant local oscillator the the transmitting section that I made. Watch Jeri Ellsworth’s Videos:

Received signal is mixed with the local oscillator (10 ish ghz) such that the result is the subtraction of the two signals, aka the doppler shift which can be related to speed.

A similar mod can be done to use these as 10ghz ham radio transmitters:


DIY Arduino Variable Lab Bench Power Supply 0-30v CC/CV

DIY Arduino lab bench power supply 0-30v 0-3a cv cc

This power supply can be built for less than $25 sans enclosure



Parts List: (see schematic)
Assorted resistors and capacitors (see schematic)
Optional: (see schematic)

Cool enclosure
Potentiometer knobs
Binding post output
Big heatsink for transistors