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Registered Member #1517
Joined: Wed Jun 04 2008, 06:55AM
Location: Chico CA
Posts: 304
aonomus wrote ...
A teaser pic of a big project I'm working on right now with a few other people from the University of Toronto... details for now are 'secret' until a certain date (in a few weeks).
Looks like a couple of microcontrollers (Arduino?) and an old CPU heatsink in the bg
Registered Member #1083
Joined: Mon Oct 29 2007, 06:16PM
Location: Upland, California
Posts: 256
tesla500 wrote ...
A 6 position parallel port switch?
Spot on. The thing was an old box to select between 5 different printers or 5 different computers to 1 printer. *gives tesla500 3 chocolate chip cookies*
Dr. Spark wrote ...
I use to have one like that in a Heath Kit tube checker in the 1960s to change the filament voltage.
Cheers, Dr. Spark
Wow. Imagine if something doesn't work, you have to check 125 wires!! What a mess
Registered Member #2123
Joined: Sat May 16 2009, 03:10AM
Location: Bend, Oregon
Posts: 312
Here are some scanning electron microscope images of a power mosfet still being fabricated.
First image is a low mag view of a corner of the die showing some of the massively-parallelled gate/source region. This is a low voltage device, hence there are fewer field termination rings around the die perimeter.
Below that image are magnified views of the gate fingers. This is what's called a 'self-aligned metallization' gate design. a single layer of metal is deposited on both the gate and source regions, then through dry and wet etch processing the metal between the gate and source contact areas is removed.
The drain contact is made on the reverse side of the chip.
While some who post here work with 35nm minmum feature size, I get to work with 20u gates and single transistor die up to the size of a postage stamp.
Registered Member #902
Joined: Sun Jul 15 2007, 08:17PM
Location: Pacific Northwest USA
Posts: 1042
my first HF Radio, my MicroHam MicroKeyer (still need the right cable for my radio ), and the very large PSU for the radio\ radio is a Kenwood TS-140S... the thing is built like a freaking tank!
also included is an overview of the current Shack. PS: notice something in one of the photos?
Registered Member #599
Joined: Thu Mar 22 2007, 07:40PM
Location: Northern Finland, Rovaniemi
Posts: 624
Some new stuff just arrived.
Duh, those are 305kVAR 13.8kVAC 5.1µF PFC/Filter capacitors. Got them cheap so couldnt resist buying. They are most likely internally fused so any pulse related stuff wont be possible. Maybe i just store them for future to be used as Filter or PFC.
Registered Member #152
Joined: Sun Feb 12 2006, 03:36PM
Location: Czech Rep.
Posts: 3384
Kizmo wrote ...
Some new stuff just arrived.
Duh, those are 305kVAR 13.8kVAC 5.1µF PFC/Filter capacitors. Got them cheap so couldnt resist buying. They are most likely internally fused so any pulse related stuff wont be possible. Maybe i just store them for future to be used as Filter or PFC.
Maybe connect them to your distribution transformer and make some monstrous resonant arcs?
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), and the very large PSU for the radio\
