Wednesday, February 27, 2013

Found it! Service manual for the Tek 468 Oscilloscope

Some day i will find time to repair my Tek 468, which is a very nice scope capable of both storage and analog mode.

Found this awesome wiki on Tek scopes which also included the service manual for my Tek:

http://w140.com/tekwiki/wiki/468

Friday, February 15, 2013

Pick up a copy of the March QST, article on the 'homebrew' 6 & 10m SSB/CW transceiver!





Very excited to finally have something published in QST!  Ever since i was a teenager i've admired the authors of QST who wrote about radio designs, power amplifiers, oscillators, and other radio electronics.

Please check out the March Edition of QST (out this month in mid-Feb).

Article on pp. 39-42
http://www.arrl.org/qst

Detailed and readable schematics, photos, and other documentation, top of:
Schematics, block diagram, additional photos and other material.
http://www.arrl.org/qst-in-depth

Youtube video of radio demo:

Additional notes and photos here.

Thursday, February 14, 2013

Interesting article on Impulse Radar by C. A. Fowler

I'm a big fan of C. A. Fowler, having one of his quotes on my website.  I had the pleasure of meeting this MIT Rad Lab engineer a couple years ago while i was chair of APS Boston.

While searching around for info on impulse radar for my book i found this interesting article about impulse radar from December '92:
http://faculty.nps.edu/jenn/Matlabradar/UWB_radar_caper.pdf

I once built an L-band impulse radar as my senior design project at Michigan State University:
http://www.glcharvat.com/Dr._Gregory_L._Charvat_Projects/L-Band_UWB_Short-Pulse_Radar.html

Sunday, February 10, 2013

The L298 & L6506 stepper motor chipset

I've been working on repairing an RMV Sport 232 stepper motor controller.

Like many controllers this one uses the L298 driver:
http://www.st.com/internet/analog/product/63147.jsp

Which closes the current feedback loop with the L6506:
http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATASHEET/CD00000097.pdf

A very interesting chip set and i'm sure it is ubiquitous in all things stepper motor.

Tuesday, February 5, 2013

S-Band FMCW Radar with Range Gate




This video demonstrates the analog range gate in action.  The analog range gate was key to imaging through concrete walls using this system:
http://www.glcharvat.com/Dr._Gregory_L._Charvat_Projects/thru_wall_radar.html
It facilitates the use of long duration waveforms for through-wall imaging while also reducing clock rate and dynamic range requirements of the radar's ADC.

For more info:
http://www.glcharvat.com/Dr._Gregory_L._Charvat_Projects/Low-Power_S-Band_Rail_SAR.html

To process data from this experiment:
http://www.glcharvat.com/Dr._Gregory_L._Charvat_Projects/Ch3_FMCW.html

Friday, February 1, 2013

Don't forget to submit your abstract today, 2/1 for the 2013 IEEE Intl. Symposium on Phased Array Systems and Technology




During recent decades, phased array systems have made major steps forward with the development of many major radar and communications systems. due to many recent advances, including MMIC, photonics, and digital beamforming, phased array systems and technology continue to progress rapidly. Current and future developments of ground-based, sea-based, airborne, and space-based phased array radar, communications, and other electronic systems will be discussed at this international symposium.

Phased Array 2013, the 5th IEEE international symposium presenting advanced in phased array systems and technologies, will be held at the Westin Hotel, Waltham, Massachusetts on Boston’s famous Route 128.

Poster Presentations

Student Paper Competition

Special Sessions