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Chris55000 · 4th Jan 2020, 11:57 pm

Hi!

Yes!

An F.M. generator frequency modulates a carrier wave over a specified frequency range (typically ±75 kc/s or ±100kc/s for an f.m. broadcast receiver, at a rate depending on the frequency of the audio modulation, whereas a sweep generator sweeps the frequency of a modulated or unmodulated carrier over a range determined by (usually) the "Sweep Range" control, and the sweeping is usually at a very low frequency compared with the instantaneous frequency changes of an f.m. generator.

A sweep generator can also sweep over a much larger range of frequencies to produce a "response curve", that can be traced on an oscilloscope directly!

For aligning conventional f.m. broadcast receivers, an f.m. generator (more cred orrectly, an f.m. modulated signal generator), is very much more convenient for f.m. i.f. alignment as the receiver's a.f. output can be used, monitored by ear or with an a.c. voltmeter, whereas a sweep generator's output needs to be monitored with an oscilloscope!

Chris Williams

4th Jan 2020, 11:57 pm	#2
Chris55000 Nonode Join Date: Aug 2007 Location: Walsall Wood, Aldridge, Walsall, UK. Posts: 2,874	Re: FM generator vs sweep generator question Hi! Yes! An F.M. generator frequency modulates a carrier wave over a specified frequency range (typically ±75 kc/s or ±100kc/s for an f.m. broadcast receiver, at a rate depending on the frequency of the audio modulation, whereas a sweep generator sweeps the frequency of a modulated or unmodulated carrier over a range determined by (usually) the "Sweep Range" control, and the sweeping is usually at a very low frequency compared with the instantaneous frequency changes of an f.m. generator. A sweep generator can also sweep over a much larger range of frequencies to produce a "response curve", that can be traced on an oscilloscope directly! For aligning conventional f.m. broadcast receivers, an f.m. generator (more cred orrectly, an f.m. modulated signal generator), is very much more convenient for f.m. i.f. alignment as the receiver's a.f. output can be used, monitored by ear or with an a.c. voltmeter, whereas a sweep generator's output needs to be monitored with an oscilloscope! Chris Williams __________________ It's an enigma, that's what it is! This thing's not fixed because it doesn't want to be fixed! Last edited by Chris55000; 5th Jan 2020 at 12:03 am.