27-06-2011, 12:46 PM
I hadn't realised that in my earlier post, I'd repeated almost verbatim an even earlier post from a couple of months ago, with the same pics. Sorry about that - it comes with age - I know my name and address, but if you ask me what time it is, I forget where I live!
I've just quickly lashed up my Heathkit RF1U sig genny to my scope and have squirted 1 MHz unmodulated, and then internally modulated by the RF1U into the scope. I've also taken a pic of a 5 MHz unmodulated trace. The traces appended below. As can be seen, the unmodulated traces are clean sine waves, (given the limitations of a budget priced kit-built sig genny some thirty years old, viewed on a Gould 300 of similar vintage rescued from the skip), but on the modulated 1 MHz trace, the effects of modulation can clearly be seen.
Of course, the problems with your sig genny might be nothing to do with the signal being modulated - it may be due to it being discombobulated - an altogether different thing!
David.
I've just quickly lashed up my Heathkit RF1U sig genny to my scope and have squirted 1 MHz unmodulated, and then internally modulated by the RF1U into the scope. I've also taken a pic of a 5 MHz unmodulated trace. The traces appended below. As can be seen, the unmodulated traces are clean sine waves, (given the limitations of a budget priced kit-built sig genny some thirty years old, viewed on a Gould 300 of similar vintage rescued from the skip), but on the modulated 1 MHz trace, the effects of modulation can clearly be seen.
Of course, the problems with your sig genny might be nothing to do with the signal being modulated - it may be due to it being discombobulated - an altogether different thing!
David.
