1. A field technician had returned a fibre optic repeater module with 
a SMPS in the box - fault tag said - 'not working', really helpful.  

I hadn't seen this particular equipment before, and the companies 
training is - 'well you know what it is', what else do you need to 
know?' So I checked the SMPS and duly got 11.84v good enough. 
Inspected the FO module - all looked OK, so connected power supply to 
unit . Uh oh, cheapo multimeter reads -1.84v (significance of value 
didn't sink in until later). Checked again for weird shorts, cheapo 
multimeter gave weird readings, deep breath, removed 7805 regulator, 
nope still wrong lifted SMD tants - nope not them, lifted power legs 
on RS232 chip, nope, lifted legs on 74756 nope. after 3 hours of this 
had brainwave, down the back of a fixture their ois one of these in 
the workshop in use - found it had a linear power supply. Asked the 
local know all, 'Oh yes, they don't have SMPS, don't why they sent 
that back'.

Reason for getting -1.84?, The polarity on the SMPS was opposite to 
that of the linear one. Of course I now have no way of testing the 
'not working' unit, as there are no test fixtures in the company - ho 
hum.

2. Arrived home the other day to discover a plague of mini ants in the 
kitchen (about the size of poppy seeds and easily mistaken for them 
except the ants move and the seeds don't). Went to make a pot of tea 
and  found them swarming all over the kettle and doing the multileg 
stroke across the water.  All sensible people know that the best way 
to rid the kettle of ants is to run it under the cold water tap. 
Common sense reigned when water started coming out of the switch 
housing - tea postponed whilst kettle was gently dried in the sun.

I need an aspirin and a 12 hour lie down.

Colin
--
cdb,  on 1/15/2010



-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist