Commodore 128 tower project continued!

[Hodgkinson]

Are you sure that you need 9VAC?

If that’s the supply to the C128 then surely you could follow the supply chain down on the C128 and wire in the +V DC supplies from the PSU directly to the C128? Probably after some regulator stage or summat?

NB. I’m guessing here, I've never had a C128. Note that you’d have to disconnect whatever’s before your feed point to prevent damage.

Just an idea.

Hodgkinson.

[Hodgkinson]

Ah ha - OK. Sounds like the supply system isn't as simple as I thought it might be.
Just make sure that you have a good thick 0v common connection between the PC PSU and the C128 PSU system to prevent any currents flowing back to ground resulting in voltage offsets due to voltage drop down other thinner wires.

Hodgkinson.

[Hodgkinson]

A bit OT, but still related to PSU's:
http://www.amiga.org/gallery/index.php?n=2386

That projects going to be scrapped due to reasons listed there. The new one, which is going to use an ATX PSU with an always-on pass-thru mains port, is going to have a 20A 12V relay rigged in line with the pass-thru, so the monitor and other devices can all be turned off from the floppy port of the A1200.

But im straying OT here... :roll:
Hodgkinson.  

[Hodgkinson]

Maybe it would work ok with just the LED and a resistor - Even on AC (The LED is a diode in itself)? OK, maybe the led would flash at 50Hz :crazy: , but this shouldn't be much of a problem.

Hey, maybe you could just use one of those LED's with a built in resistor?

Just a thought (Nicely done anyhow),
Hodgkinson.

EDIT: What's the relay switching? The 9VAC side or the mains side of the transformer? If im right in saying it’s a reed relay; they aren’t normally designed to switch much current. Maybe a 100mA or so at most, and not usually mains either.

EDIT2: Hey, what about having a high current relay, controlled from the ATX PSU, switching the mains side of the transformer? That way, you can save on the energy costs of having the transformer powered up all the time, and you can use a neon indicator (W. resistor of course) on the mains side rather than trying to use a LED.

[Hodgkinson]

Doh. ;-) Coil O/C? That’s odd...The only time we've had that happen is when the relay was virtually full with water for half a year...

I'd still advise a nice chunky standard relay :rtfm:

Hodgkinson.

[Hodgkinson]

Why can't we put them in our miggies? :crazy:

BTW, Congrats on winning the auction  ;-)

Im a bit confused as to how thats actually going to connect to your C128...


Hodgkinson.

[Hodgkinson]

> A more heavy duty PC relay is now used.

;-)
Hodgkinson.

[Hodgkinson]

:lol: Well, at least its better than my XP tower - Whenever I use the motherboard USB sockets, and come to turn it off, windows shuts down, there's a click, and the machine stays on! Avoid the mobo USB, and it turns off fine every time (Including during crashes :crazy: )


Hodgkinson.