I've recently become acutely aware of the shortcomings of my signal generator.
It is a Heathkit SG-6. It is really old. It has a selenium rectifier in it. It has one of those old mic connectors on it for the output. The output is very low. But I like the cabinet and there is a nice switchable coil/variable capacitor LC circuit in there (see above).
In 2008 in Hyderabad, India Farhan went to McDonalds with his kids and went home with some straws. Soon the straws are chopped up and turned into coil forms for a signal source: http://www.phonestack.com/farhan/siggen.html
So here is my idea: de-tube the SG-6. Turn the selenium over to the HAZMAT authorities. Save the coils and the cap and most of what George Dobbs would call "the socketry." Use an MPF-102 for the oscillator, then make use of the buffer and feedback amp from Farhan's soda straw circuit.
What do you guys think?
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Hi Bill,
ReplyDeleteFor inspiration, I refer you to an article that may be found at a familiar web site:
http://www.hanssummers.com/bc221t.html
73,
Clint
KA7OEI
I've already done that to an IG-102:
ReplyDeletehttp://km5z.us/blog/?p=67
Actually it's a 73 Magazine article (which was later put into a book of test-gear projects, by 73 Mag).
Works quite well. I replaced the Light Bulb with a Red LED, and the whole shebang works off a 9V battery.
I was careful to save the tubes and the HV/Filament transformer for other projects.
Mike Y
KM5Z
Dallas, Texas