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Re: Two more silly II questions...
zwsdotcom@gmail.com wrote:
On Aug 23, 4:34 am, demp...@actrix.gen.nz (David Empson) wrote:
feeding +12V to the input side of the fuse, with ground connected to
What was your +12V source? It could be a current issue, or 12.0V might
not be enough.
Adjustable two-channel lab power supply, max 10A@20V. I started with
the current-limiter set at 1A, but the supply never went into limit.
With the power switch OFF, the IIc drew 50mA (ish). With the switch
ON, it spiked briefly then dropped to ~10mA. Yes this makes no sense.
It makes perfect sense. When you switched on the IIc, there was a
large current surge as it tried to charge its capacitors. Your lab
supply promptly limited the current by dropping the voltage below the
minimum that the IIc will work at. The IIc supply then shut down.
If your connections are correct (the pinout is on the web--Google is
your friend), then the 12v supply will work perfectly if the current
limit is set higher to handle the inrush current.
It could also be a ground issue. Chassis ground might not have a direct
connection to the ground pin in the power supply connector.
Stick with the power supply connector--that's what it's designed for.
I also tried using the ground pins of the PSU connector as my ground
point, with identical results :(
Right--see above.
-michael
NadaNet file server for Apple II computers!
Home page: http://members.aol.com/MJMahon/
"The wastebasket is our most important design
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