Gary's Electronic Hobbyist Page

A few of the Projects I've Designed and Built

DTMF to RS-232 converter
Noise receiver/counter for Solar radio astronomy (Solar Telescope Using Radio Amateur Technology - STUART)
2304 MHz to 28 MHz Transverter
9600 bps Data Radio (20.6 MHz IF)
180 KHz 1 Watt CW Transmitter
Automatic Morse Code Message Generator
100-300 KHz Tuneable Active Loop Antenna

At some point I may put up schematics or plans for some of the above designs. But they're not available at this time.

Products

HF Active Antenna kits

RFCAD Electronic Design Software package

Electronic Component Distributors

Digi-Key

Mouser

Radio Shack

Some Other Electronic Design Links:

Nuts and Volts Magazine

Electronics Tutorial Site

PCBpro.com - Printed Circuit Board Design and Prototyping

Calculators Galore (Everything you can imagine)!!!

Home Automation Info

I am experimenting with X10 technology to automate and secure my home. So far, I have motion sensors that light the driveway and patio area. These also trigger chimes to alert us that someone is arriving (and when cats run down the driveway...). My wife also uses X10 modules to turn the Christmas decorations on and off.

I've not been too impressed with the unreliable nature of the X-10 signals over the power line. I've spent a great deal of time and effort getting it the best I can, but it's still mediocre at best.

Note: One thing worth mentioning that I haven't seen in any of the articles I've read about X10; Beware of surge suppressor units that have "noise filtering". These frequently contain a .1uF to .47uF capacitor directly across the power line! This essentially "shorts out" the 120 KHz X10 signals. This would be OK if it was only for the outlet strip with the filter in it, but it also eliminates X10 on all circuits it's plugged into. Once I tracked these down, I added a series torroid inductor (MagneTek CMT908-V1 [Rated 7.5 Amps]) to the filter circuit on each one and all was well with X10. Also, my wireless intercoms magically worked much clearer. Home Automation Systems now sells a thing they call "FilterLinc" for about $35 that solves this problem. It's basically a 120 KHz band-reject filter that can handle 10 Amps. I opened mine up to verify the design and drew this PDF schematic of it.

For security, I've set up five color/Infrared (day/night) cameras around the perimeter of my house. The video from these is continuously recorded to a stand-alone DVR with a 120 GB disk at 15 frames/sec. Most of the cameras are hard wired, but one uses a 2.4 GHz video link because it was too difficult to run video cable to it. The driveway is also covered by an Infrared illuminator that points down the driveway and an extra sensitive C-Mount camera with a 5-50 mm zoom lens to capture action down at the street. The DVR can be accessed remotely over the LAN or even over the Internet.

Some Home Automation Equipment Suppliers:

Home Automation Systems

Discount Security Cameras (DVRs and cameras)

X10.COM

Radio Shack

CE Bus Home Page

Equipment I Want to Buy:

email me

Nothing Currently

Equipment I Want to Sell:

HP 8970A Noise figure meter with HP 346B noise source. (Noise source needs work. Probably just the diode)

If you are interested in buying any of these from me, please email me to negotiate a price and delivery method.

Equipment Service Manuals I Need:

Ballantine 320A True RMS Voltmeter
Ballantine 421A Voltage Calibrator
Chronetics PG-10 Pulse Generator
General Microwave Model 471 Power Meter
HP 181T Display Unit
Kruse Stork 5000 Sweeper and any of its plug-ins
Wavetek 112 Function Generator
Wavetek SAM III CATV test set

If you have any of the above manuals, I would like to either buy it from you,
borrow it and make a copy, or pay you to make a copy. Please email me to arrange a method.

Thanks!

Updated: December 2, 2007