[Paul Philco322]

The latest set I have got running is a Zenith H723, nice little AM/FM Z brand. Was very clean and sounds very nice, pretty sensitive. 

https://www.radiomuseum.org/r/zenith_h723_ch7h04.html

I doesn't display much if any FM drift but does not have AFC. Which made me wonder when did AFC show up? I have a Zenith from the later 60's with AFC.

My question would be if some early sets without AFC can play fine, why did they need to add AFC? Were some sets manufactured in a way where they had bigger drift issues?

Appreciate your thoughts.

PAul

[David]

   
Sorry I can not answer your question, but living in the country 30 miles to FM station I notice some drift over time without AFC. Here is one I restored a few years back. Have several Z sets very much alike some with AFC some without.

[Paul Philco322]

Perhaps Signal strentgh is a contributor?

Paul

[Radioroslyn]

Generally speaking it wasn't till the mid 50's that afc was incorporated. If you are looking for good performance stay away from the late 40's/early 50's fm sets.

[David]

If one would like to compare the different circuits this has AFC. this set is one my Late father in law owned which I was able to restore.     i

[Paul Philco322]

Thanks for taking the trouble with the Diagrams, I have several later model AM/FM Z's and they are good players even some cheaper ones from just before they stopped making them.

Paul