Peter L. Peres wrote:

>
>
> On Thu, 3 Feb 2005, Ake Hedman wrote:
>
>> I have two identical boards on my desk  and have some noise problems=20
>> with one of them. Both have a sensor input and a cable of about two=20
>> meters attached to the input plus are connected to a CAN bus. The=20
>> sensors are decouples on the board with a 0.1uF cap. Above my bench I=20
>> have a fluorescent lamp and one of the boards get very upset=20
>> (watchdog reset) when this lamp is turned on/off.
>>
>> First it is strange that only one board does this but my question is=20
>> how do one approach a problem like this?
>> I have also tested a piezo gas lightning device close to the boards=20
>> but it does not disturb the systems.
>
>
> Are the boards new (never worked) ? Imho you are looking for a cold=20
> solder joint or cracked part (cap, resistor), likely in the grounds or=20
> decoupling areas. If you have a fox (from a fox&hound set) you can try=20
> injecting signal into the ground at various chips and see if it is=20
> sensitive.
>
> Peter

Yes it looks like that was the problem. at least part of it.

But Pete... a fox, from a fox&hound set???  Can I use one of my cats=20
instead... ;-) What is it?

Regards
/Ake

--=20
 ---
Ake Hedman (YAP - Yet Another Programmer)
eurosource, Brattbergav=E4gen 17, 820 50 LOS, Sweden
Phone: (46) 657 413430 Cellular: (46) 73 84 84 102
Company home: http://www.eurosource.se     =20
Kryddor/Te/Kaffe: http://www.brattberg.com
Personal homepage: http://www.eurosource.se/akhe
Automated home: http://www.vscp.org


--=20
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