[Amps] re cooling of coils

[Harold B. Mandel]

PAPST manufactures a wide variety of muffin fans. In the DIGI-KEY
web catalog, users can bring up the dB ratings of the various models.



> Hams - especially the new generation of "baby broadcasters" - want 
> amps that sit quietly on the table. In contrast, CB "amp contesters" 
> actually  *want* to hear those mighty engines roar. In both cases, the
maker 
> aims to please the market.
> The cure for that is to add the optional Muffin-type fan on the air 
> inlet. It doesn't increase the total airflow much - its main purpose 
> is  to make the incoming air very turbulent, so the transformer is 
> cooled  much more *efficiently* (along with most of the other
components on 
> the  power-supply side). But the price for that is a noisy fan, right 
> onto  the rear of the amp where you can hear it.
> I don't know what type of fan they supply, but low-noise Muffin-type 
> fans are available that are at least 10dB quieter than the regular 
> type.