[aprssig] Confusing situation

Andrew Rich vk4tec at people.net.au
Wed May 14 09:13:18 EDT 2008


Ever have one of those days ?

1. I have a little plug pack with a variable slider 12V, 9V etc
2. The plug pack powers a PIC development board (PIC and MAX232)
3. The development board has a MAX232 on board which I am using to send to the laptop.
4. Data was coming in on the radio chip, and 5 volts logic was being presented to the MAX232. (used a CRO)
5. Tried a different USB / Serial converter - same, no data in hypertrm
6. Reboot windows.
7. It turned out that the little plug pack had slid from 12 volts to 9 volts.
8. It was enough for the little LED cct to show it was working, but not enough to get the MAX232 to work.

Annoying.

Loop back on serial worked - just to confuse me even more.
Looked on PIN 2 with a CRO and saw data - but the CRO ust a high Z and did not load up the cct.



-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.tapr.org/pipermail/aprssig_lists.tapr.org/attachments/20080514/6f52a16b/attachment.html>


More information about the aprssig mailing list