Audio Generator vs. Signal Generator...

[lclingman]

I'm new to the electronics hobby.

I'm building an AM/FM radio kit I got from Make:. In the instruction manual, during testing the circuits, it references using an "Audio Generator". Is this just another name for a signal generator, or is it something else altogether?

Thanks in advance,

Lyle

 

[(*steve*)]

In a simplistic way, an "audio generator" is a signal generator that is limited to frequencies I'm the audible range. Most signal generators have a frequency range that is much wider.

 

[lclingman]

In a simplistic way, an "audio generator" is a signal generator that is limited to frequencies I'm the audible range. Most signal generators have a frequency range that is much wider.

Thanks for the fast response, Steve!

So I could just use a signal generator set at the appropriate frequency then?

 

[(*steve*)]

I can't see why not.

 

[davenn]

So I could just use a signal generator set at the appropriate frequency then?

Basically, there are 2 types of signal generators with two very different uses

Audio signal generators that cover the audio frequencies essentially around 10 Hz to around 20 kHz
these can have various modes of output eg sine, square and saw wave outputs
Often these are combined in a package called a function generator and may go up to a few MHz
and have digital modes as well for testing digital / logic circuits

RF ( radio frequency) signal generators often cover the range of around 10 kHz up to many 10's of GHz (microwave frequencies)
my one goes from 10 kHz to 8.4 GHz ... they get pretty expensive as the frequency climbs higher

Audio generators you use to test the audio stages of your AM/FM radio kit, from the detector/demodulator stage to the speaker output

RF generators you use to test all the RF stages from the antenna input through the RF amplifier stages, local oscillators, mixers, and IF stages
up to the detector/demodulator stage.

so you can now see there are two very different beasts


Dave

 

[(*steve*)]

What do you call one that goes from 0.01Hz to 20MHz? . I have another one that goes up to 990MHz, but I can't remember the lowest frequency off the top of my head.

Other than frequency range, there are very few features that you couldn't find in both an audio signal generator or an rf signal generator.

 

[73's de Edd]

On the one with the LOOOOOW frequency I call mine a wave form or Function generator . . . . it being a Wavetek brand
If it needs to be set close I also have a digital .001 Hertz thru 10 Mhz generator.
(Praise be to NASA Surplus Property Disposal and friends in low places. )

 

[Audioguru]

What is there in the audio part of a radio to adjust using an audio generator?
Usually an audio circuit is designed to work correctly. Maybe the kit is showing you how to fiddle with adjustments to make it work correctly?[/B]

 

[davenn]

What is there in the audio part of a radio to adjust using an audio generator?

usually nothing adjustable.... but an audio source is great for finding why audio isn't getting from the detector stage to the speaker
being able to tone out the audio path is sometimes an essential test proceedure

 

[73's de Edd]

BTW . . .give us the brand or a URL lead and then we can see EGG-ZACTLY what you will be involved with and up against. I might initially expect it being one of Carls project radios or an El enco.

 

[Audioguru]

My first project was a audio amplifier kit that used vacuum tubes that I fed from a vinyl records turntable. My second electronic project was an FM tuner kit (also using vacuum tubes) and it worked perfectly. My third project was a stereo multiplex adapter kit for the FM tuner. For all of them I did not use a signal generator to adjust them.

 

[davenn]

For all of them I did not use a signal generator to adjust them.

since none of them were repair jobs .... you statement is correct, but it has nothing to do with the repair job that the OP is conducting

 

[Audioguru]

Repair job? Where?