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Registered Member #1792
Joined: Fri Oct 31 2008, 08:12PM
Location: University of California
Posts: 527
Sulaiman wrote ...
For my radio hobby I'm using a couple of fets for >100W CW at >2 GHz. There is no point considering such a high frequency for a TC as 1/4 wavelength is 35mm.
Couldn't you make the coil a larger odd number of quarter wavelengths, e.g. 3/4 wavelength? Not that there is necessarily a good reason for doing that as opposed to lowering the frequency... unless you just want bragging rights :)
Registered Member #1225
Joined: Sat Jan 12 2008, 01:24AM
Location: Beaumont, Texas, USA
Posts: 2253
Steve McConner wrote ...
Sulaiman wrote ...
For my radio hobby I'm using a couple of fets for >100W CW at >2 GHz. There is no point considering such a high frequency for a TC as 1/4 wavelength is 35mm.
Yes there is! Just stick 70mm of wire in a microwave oven, streamers burst from both ends, et voila a microwave VTTC.
I've seen foolhardy people on Youtube run a magnetron removed from the oven with a sharp point attached to the antenna, and it really does break out and make a plasma flame.
Silicon carbide power JFETs recently became available, I wonder how fast they go?
Registered Member #63
Joined: Thu Feb 09 2006, 06:18AM
Location:
Posts: 1425
Steve McConner wrote ...
I've seen foolhardy people on Youtube run a magnetron removed from the oven with a sharp point attached to the antenna, and it really does break out and make a plasma flame.
Registered Member #1667
Joined: Sat Aug 30 2008, 09:57PM
Location:
Posts: 374
Luckily few people on the net give easy explanations on how to construct waveguides (compared to those that talk about microwave weapons) I found, lately...
SiC jFETs seem to be awesome devices, unfortunately I don't understand a single word of this:
Does anyone know know a good source of detailled information about SiC semiconductors?
Registered Member #2123
Joined: Sat May 16 2009, 03:10AM
Location: Bend, Oregon
Posts: 312
Google "Wide Bandgap Semiconductors". Look up the differences between 4H and 6H subtrate device fabrication (e.g. 6H SiC:GAN is used for blue lasers).
See what kind of literature Cree semiconductor has posted. Although it's not been given a lot of publicity, Cree has introduced a SiC mosfet for solar inverter applications.
I have ITAR and Company Confidential tape over my mouth when it comes to what we're doing with SiC where I work so I can't go beyond Microsemi press releases. Go to Microsemi's website and look up what they have posted on SiC.
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Fastest Transistors
