[sdiy] 1N914 vs. 1N4148 ?

[Harry Bissell Jr]

OK  that makes sense. The faster recovery would allow
a smaller reverse current, which would stimulate the
LC (line inductance and parasitic capacitance) less.

OTOH the 'snappier' turn-off would make the higher
harmonics ring more (but for less time).

The snubber idea is the best course, of course.

At least now i know what they 'were thinking' 

Thanks.

H^) harry

--- The Peasant <ecircuit at telus.net> wrote:

> 
> > Has anyone seen people using fast recovery diodes
> in
> > 60Hz power supplies ??? What's up with that ???
> > 
> > Is it some audiophile thing ???
> 
> Yes.
> 
> When the ac cycle reverses the bias on a silicon
> diode, it tends to ring at 
> high frequencies. (This ringing can be seen on a
> good oscilloscope.) This high 
> frequency ringing can end up modulating the power
> supply and/or the audio 
> signal, and can make quite a difference in sound on
> a good stereo system. Fast 
> recovery diodes do not exhibit this problem nearly
> so much, and so using them 
> will minimise this source of "noise". However, I
> have found that using a 
> snubber network across each rectifier diode of a
> standard silicon bridge will 
> also cure this problem, I use 0.01uF in series with
> a 100R resistor for this. 
> And this solution is a lot cheaper than using those
> expensive fast recovery 
> types.
> 
> Take care,
> Doug
> ______________________
> The Electronic Peasant
> 
> www.electronicpeasant.com
> 
> 
> 
>