[ARC5] 24vdc power

[kn7sfz]

OK, I'm sold.....full wave it is!

If I understand it correctly, just two diodes would require a center 
tapped 48vac xfmr, probably a little harder to come by than 24vac and 
bridge or mebbe two of the latter in series to achieve center tapped?

Keep the great info coming...my brain is full but I love to learn!

Richard kn7sfz



On 9/5/2022 5:15 PM, scottjohnson1 at cox.net wrote:
>
> You don’t necessarily need a bridge, but it should be a full wave 
> rectifier, otherwise it is very inefficient. In a high current supply, 
> it would also cause a great deal of power dissipation in the filter 
> capacitors.  Half wave rectifiers are best left for very low current 
> applications.
>
> Most battery charger use a full wave center tap rectifier , which 
> requires only two diodes.  It is slightly more efficient than a 
> bridge, since there are two fewer diode drops (0.6V @ 100 A would mean 
> 60W dissipated per diode).   Dynamotors do not like raw rectified AC 
> and will run hot.  Obviously, filaments don’t care, but the RMS value 
> needs to be correct for proper emission. So, really, the KISS method 
> is the minimum acceptable of a stiff, filtered, full wave supply.  If 
> it is sufficiently sized, load regulation will probably be acceptable.
>
> *From:* arc5-bounces at mailman.qth.net <arc5-bounces at mailman.qth.net> 
> *On Behalf Of *kn7sfz
> *Sent:* Monday, September 5, 2022 1:55 PM
> *To:* arc5 at mailman.qth.net
> *Subject:* Re: [ARC5] 24vdc power
>
> Man....all this info is great!
>
> And with regards to building an xfmr 'brute force' supply, do you 
> really need a bridge rectifier or will half-wave do?
>
> Do dynamotors and filaments really care if there's a bit of ripple?  I 
> have some large diodes and caps I could put to experiment with.  Kinda 
> the KISS method.
>
> de kn7sfz
>
> On
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/arc5/attachments/20220905/29679a2c/attachment-0001.html>