RE: A little electronics help

From: Charles Overy (cwho@lgmmodel.com)
Date: Thu Sep 05 2002 - 22:42:23 EEST


Ken,

I agree that there is a risk of blowing up your power supply if you are not
careful

It is a little difficult to figure out without knowing what the old switch
did and looked like. Did the old switch light up when it was on? Was the
old switch a push button or a toggle? Is this one of those big red toggle
switchs that used to be on the side of older PCs?

Best bet is to plead with service at Sanders or annother user to pull one
appart there to have them tell you what happens to leads 1-4 when the
original switch is swithed. Then it is fairly easy to duplicate that
functionality with the new hardware

Baring that, if you could send a JPG picture and describe the functions,
features and markings of the old and new switches it would be possible to
do a more educated guess. Also if you have a continuity tester, can you do
a "pin out" or function test of what it used to do. I realize that it is
broken now but perhaps we can learn something about how this old switch
worked.

It looks like your new switch is what is called a double pole, double throw
switch. IF so it should be marked DPDT. If this is true, basically you can
connect two separate circuits with the one switch. When it is in one
position lead 2 connects to lead 1 and lead 5 connects to 4, when the
switch is in the other position lead 2 connects to lead 3 and lead 5 to lead
6.

If I had to GUESS would be that your terminals 1 and 2 on your power supply
are the 110. This would be true if they were bigger looking than the other
wires. As long as your new switch is rated to switch 110V (and the right
amperage) then you can connect them to 4 and 5. Then maybe you want to
switch 3 and 4 together on the power supply with connectors 1 and 2 on the
new swithc but it is very difficult to tell. You can try this, chances are
that you wont destroy anything but only you can decide how much you are
willing to gamble and without more info it is a gamble.

Perhaps there are people on the list who have experience with the particular
power supply in question.

There is no definative standard that 1 goes to 1 or black goes to white.

Let me know if I can help more.

Good Luck

Charles

-----Original Message-----
From: owner-rp-ml@rapid.lpt.fi [mailto:owner-rp-ml@rapid.lpt.fi]On
Behalf Of ken
Sent: Thursday, September 05, 2002 10:36 AM
To: rp-ml@rapid.lpt.fi
Subject: A little electronics help

I have an RTM, which has been running beautifully for months, but has run
into an annoying little prob.

the main computer power switch is dead. I can't find any close to the
original around mid town NYC,
and the one I did find...

here are the schematics. I don't want to plug anything together until I'm
100% sure it will work.

Is there anyone with an electronics background that can help me out. I need
to get it running today, and since Sanders buys the computer from a
supplier, they don't have the switches laying around. Its pretty simple,
but I never had to deal with this kind of thing.

TIA.

ken

-----Original Message-----
From: owner-rp-ml@rapid.lpt.fi [mailto:owner-rp-ml@rapid.lpt.fi]On
Behalf Of ken
Sent: Thursday, September 05, 2002 10:36 AM
To: rp-ml@rapid.lpt.fi
Subject: A little electronics help

I have an RTM, which has been running beautifully for months, but has run
into an annoying little prob.

the main computer power switch is dead. I can't find any close to the
original around mid town NYC,
and the one I did find...

here are the schematics. I don't want to plug anything together until I'm
100% sure it will work.

Is there anyone with an electronics background that can help me out. I need
to get it running today, and since Sanders buys the computer from a
supplier, they don't have the switches laying around. Its pretty simple,
but I never had to deal with this kind of thing.

TIA.

ken

For more information about the rp-ml, see http://rapid.lpt.fi/rp-ml/



This archive was generated by hypermail 2.1.4 : Tue Jan 21 2003 - 20:14:15 EET