Search found 5 matches

by [email protected]
Tue Apr 09, 2002 6:12 am
Forum: General Discussion
Topic: LM 386 + PDA+ PS = Noise
Replies: 4
Views: 2664

Re: LM 386 + PDA+ PS = Noise

Anyway the problem has been solved..
I used audio isolation transformer
on the output from the headphone jack..<p>Regds
Allan
by [email protected]
Mon Apr 08, 2002 7:04 am
Forum: General Discussion
Topic: LM 386 + PDA+ PS = Noise
Replies: 4
Views: 2664

Re: LM 386 + PDA+ PS = Noise

I just tried using a 7809 regulator on
the LM380 side, same problem..<p>It is very hard to get rid of this noise..
In fact I tried other 12->5v LM317 based
stepdown transformers same problem..
Regds
Allan
by [email protected]
Mon Apr 08, 2002 4:58 am
Forum: General Discussion
Topic: LM 386 + PDA+ PS = Noise
Replies: 4
Views: 2664

Re: LM 386 + PDA+ PS = Noise

Hi I just built a few different circuits using different amps: lm380 and Tba820M<p>the noise is dramatically less than the LM386...<p>Ok the Noise is a high frequency 'hum' When the PDA power supply (12v to 5 v) is disconnected, clean sound, no hum<p>if the PDA is switched off, no noise at all even ...
by [email protected]
Sun Apr 07, 2002 7:12 pm
Forum: General Discussion
Topic: LM 386 + PDA+ PS = Noise
Replies: 4
Views: 2664

LM 386 + PDA+ PS = Noise

Hi Regarding my earlier post on fade in/out I decided to Kiv that for a while.. So I built a quick kit of an LM 386 amp and I had the following problem<p>Power Source= Cigaratte lighter LM386 board is powered direct from 12++ volts in the car. Power is smoothed using a 1000UF and a 10UF capacitor<p>...
by [email protected]
Tue Apr 02, 2002 11:17 pm
Forum: General Discussion
Topic: AutoFade in/Out W level control circuit needed
Replies: 3
Views: 1783

AutoFade in/Out W level control circuit needed

Hi I need some help on the following:<p>I have installed a PDA and a garmin GPS in my car and the Oziexplorer CE software I have, allows me to execute a voice file when I am near the proximity of waypoint..<p>However , I don't want to stick a small radio shack amplifier to my PDA so that I can hear ...