OT: american vs european 220 - test-drb@ccmp.vtda.org

6 Feb 2011

...

  SPX graphics adapter which was plugged into a
very nice VR297 monitor (Sony
 Trinitron). I plugged out the monitor cable from the back of the Vaxstation
 for some reason. When I plugged it back in I felt a zap. On investigating,
 the earth pin in the IEC plug going into the monitor didn't seem to be
 making proper contact for some reason. The monitor didn't mind a bit but one 
I've neve seen that happen. Normally it's due to a wire having fallen off 
in one of the connectors. Of course tend to prefer the rewirable IEC 
sockets so I can check the wiring and make sure the contacts aren't bent 
open/ 

After unplugging and reinserting the plug (line socket?) once, I couldn't get
it to fail to make contact again. The connector was moulded but it was possible
to squeeze the contacts by inserting a small flat screwdriver between the
contact and the body. I decided it was better to discard the lead and use
another.

(I fitted a rewirable IEC connector on the vacuum cleaners lead after the cable
failed near the original moulded connector. The new connectors body is too
flexible and the rubber strain rellef sleeve regularly works free from it...)

...

  I traced the connections on the graphics card and
found the RGB outputs came
 directly out of a large, probably expensive, difficult to replace and rare
 looking BT459 RAMDAC :-( 
I asuem that's a Brooktree part from the number. They are not mormally 
custom chiups, you even find them (although probably not the right one) 
on old VGA cards. 

Yes, it's a Brooktree part. I don't come across that many old VGA cards and
any that I have come across don't use it. If anybody has an old card with
a BT459 that they are willing to give/sell me, I would have a go at changing
it. A quick tally shows it to have 132 pins but it looks like they are 0.1in
spaced so I should have a realistic chance of dealing with it.

Maybe I should put this in another posting as the people with large stashes
of BT459s and think this is an off-topic discussion about mains voltages
might not realise we have drifted back on topic again :-)

...

There is a locking assembly avaialble, but few manufacturers seem to use
it. And it doesn;t work with moulded scokets (see above ;-)).

I've seen a simple wire retaining mechanism (on Cisco 1U high kit I think)
which seems to do the job and works with almost any leads, moulded or not.
However, I'd prefer something that just felt a bit more secure without
needing this extra mechanism.

...

What mains connector do you prefer?

Given that almost all the kit I use has IEC connectors, I don't really have
any I prefer, just ones I don't like that much :-)

I once bought variable bench power supply at a ham rally for a very small
price. The obvious snag was that it didn't have a mains lead and the mains
input connector was an oblong thing a little flatter than an IEC chassis
mounted connector. I removed the original connector, made the hole a little
larger and fitted a new IEC connector. There's no shortage of IEC leads and
I don't want to end up needing a selection of different power leads for
different items. Sometimes it's easier to put up with something I'm not
than keen on. Even if they don't feel that secure, I can't argue with the
sheer numbers in use and the small number of reported problems with them.

Regards,
Peter Coghlan.