Quote:
Originally Posted by Notimetolooz
Well the Heathkit doesn't have a very nice sine wave output but it usually does not matter. The SG-8 like many generators used for radio-tv repair are what is known as "service grade" as opposed to "lab grade". A sinewave that doesn't have the right shape has harmonic distortion. That means that a 1Mhz output also could contain 2MHz, 3MHz, 4MHz, 5MHz, etc. Many times just the odd harmonics. However the tuned circuits in a radio-tv reject the harmonics for the most part, so they don't really matter in practice.
Also the service grade generators do not keep the signal amplitude the same as you change the frequency. However you can monitor the amplitude if you need to and adjust the amplitude as you change frequency. Maybe not as convenient, but you can make it work. Most of the time you don't change the frequency that much anyway.
The frequency dials on service grade generators are not as accurate so if you must have the frequency exact a frequency counter is a good addition to the set-up.
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That's what I thought. The guy on the Philco Phorum basically said the same thing. But the thing is, I'm just repairing old tube radios and stereo receivers so lab quality gear like the Hewlett-Packard units are not what I need.
I just need something to get me close enough to make the radios work again as intended, it's not like I'm designing new radio circuits where you would need something like a lab grade unit for.
Most of the units I'm repairing are units that are already working circuits but just need to be touched up, so a regular bench grade unit is more than enough for the work I'm doing.