[sdiy] percusion synth design and problems.

[male man]

what is a good upgrade for a SIP LM386?  i have some
crappy mixers that use these, and i think the chips
are blown anyway.  a pin for pin replacement would be
nice, cause they are SIP to save space and there isnt
much space to spare, i.e. adapting out to a DIP would
be a bit hard its so cramped in there.

thanks for the help.

skot


--- harrybissell <harrybissell at prodigy.net> wrote:
> Hi Arun...
> 
> The LM386 amp is like walking around with a sign on
> your back that says
> "Kick ME !!!".   It is almost sure to pick up radio
> and even the pros would
> have a tough time...  Check out the device datasheet
> and make sure you are
> using the AM noise reduction techniques... you might
> even be re-radiating the
> noise to yourself....
> 
> National Semiconductor Audio/Radio Application Book
> (1980) says
> 
> AUDIO RECTIFICATION ELIMINATION TIPS
> (or how come my phono detects AM ?)
> 
> a)  Reduce input impedance
> b) Place capacitor to ground close to input pin or
> base (~10-300pF)
> c) Use ceramic capacitors
> d) Put ferrite bead on input lead close to device
> input
> e) Use RF choke in series with input (~10uH)
> f) Pray
> 
> H^) harry
> 
> Arun Bohm wrote:
> 
> > Hi, Was working on this here percusion synth idea
> and was wondering why,
> > instead of damped oscillations, I was getting so
> much noise. Because I am a
> > novice, I am used to making the mixing stage from
> manuals I got from radio
> > shack(don't laugh, please) the amp I use is a
> utility amp using a 386 chip.
> > The end result is all this RF transmission (I
> actually get some AM station)
> > and a bunch of noise. What can I do to eliminate
> this problem? Any
> > suggestions would be appreciated.
> > arun_bohm at hotmail.com
> >
> >
>
_________________________________________________________________
> 


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