[sdiy] very cheap oscilloscope & signal generator?

[db]

I just fried my mp3 player this way, so don't want to do that again.
If I accidentally touch 5 or 12v to the headphone output it destroys the 
player.
What is the layout of using a diode or caps to protect for that happening 
again?

I'm hoping theres a very simple (protected) signal generator circuit somewhere.



At 11/30/2009 06:09 AM, MTG wrote:
>eBay.  Search for "USB OScilloscope".  I once had a BitScope but it was 
>neither good or cheap.
>
>A 555 is cheap enough to replace if you fry it.  Just put a socket 
>in.  But in any event a couple diodes might help, depending on what you 
>are doing with it.  You can also get a Creative Muvo MP3 player for 
>peanuts now (on eBay), and probably other brands too.
>
>GB
>www.musictechnologiesgroup.com
>San Juan Capistrano, CA
>
>
>----- Original Message ----- From: "db" <dbarton at pacbell.net>
>To: <synth-diy at dropmix.xs4all.nl>
>Sent: Sunday, November 29, 2009 4:37 PM
>Subject: [sdiy] very cheap oscilloscope & signal generator?
>
>
>>
>>
>>I'm looking for a *very* cheap oscilloscope that would be used only for 
>>audio signal tracing.
>>I envision a probe with a USB jack at the other end, and software to do 
>>it all.
>>Does anyone make a very cheap PC based scope that's usable?
>>
>>Also, I was using my mp3 player as a signal source, and it got some dc on 
>>the output, and fried it.
>>Now I'm looking for a very cheap signal injector too. Is there something 
>>like a 555 circuit with some output protection in it, that is very cheap 
>>to make or buy?
>>
>>I need these for just a few hours every few years, so cheap is the key.
>>
>>
>>
>>
>>
>>dennis.barton:skylab2000[socal]
>>
>>
>>
>>_______________________________________________
>>Synth-diy mailing list
>>Synth-diy at dropmix.xs4all.nl
>>http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>>
>
>_______________________________________________
>Synth-diy mailing list
>Synth-diy at dropmix.xs4all.nl
>http://dropmix.xs4all.nl/mailman/listinfo/synth-diy


dennis.barton:skylab2000[socal]