[sdiy] Re continuity tester:

[René Schmitz]

If one uses a 7555 anyway, then one can make the "resistance" of your 
connection set the buzz frequency of the speaker. Something like that was a
while ago in Elektor, have to dig it up. 

Cheers,
 René




At 11:03 08.06.01, you wrote:
>Ah well, I agree with you, Paul.  I hadn't thought of
>this case, and surely a continuity tester would help
>here.  An ICM7555 may also be used as a multivibrator,
>and it's CMOS, so also battery friendly (the data sheet
>says power supply current typical is 80 microamps).  It
>will also run from 3 volts.
>
>pfperry at melbpc.org.au wrote:
>>I don't agree with Scott on this one. Suppose you have a 
>>intermittent short or break in a lead, you can detect it by 
>>shaking the cord while the continuity tester is connected & 
>>listening for little bips. You can't do that with a meter, plus 
>>you have to look at the meter! Also, in troubleshooting, is is 
>>REALLY rare that a 'low ohms' connection will trip you up. If it 
>>is something you made yourself, usually you are looking for 
>>shorts. If you are repairing, you are usually looking for breaks. 
>>A two transistor multivibrator running on 3v makes a useful 
>>continuity tester. paul perry Melbourne Asutralia -- Message sent 
>
>
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