question about a circuit and clean/dirty power...

[gymbo86]

Hi,

Got two questions;

1). I need a three way switch which to operate a cd drive tray. Basically
I've ripped out the guts of an old non working cd drive stuck a piece of
sheet metal on the tray and I want to use it as a remote projector shutter.
I need the circuit design for the switch.
Position one: Would be tray out
Position two: Off (no change)
Position three: Tray in.


2). Clean and dirty power what can you tell me about it. How can you filter
power to remove periodic buzzing on a sound system.

3). Opps I've added an extra one... How many volts in a common Australian
three phase outlet..


Thanks for the help in advance.


gymbo

 

[kc5cqw]

Look at http://www.palomar-engineers.com/RFI_Kit/rfi_kit.html
You can also try some large capacitors. I would use the 2x rule: twice the
needed voltage/power specs. needed. Thus, if you have a line voltage of
220v, use a cap rated for 450v. Put the caps across the power supply output
terminals. Also put the toroids on the AC line input and on all of the audio
outputs.
Chances are, if you can hear a buzz, you may be sinding out RFI. Also,
your chances of reciveing RFI are very high. Most consumer electronics have
VERY poor filtering in order to cut production costs.
A standard DPDT rocker or toggle switch with a center "off" position
should work for your cd drive. Wire it up in a criss-cross like this: Top
left to bottom right, and top right to bottom left. Connect the center
terminals to the servo motor in the drive, or the open/close circuit.

DPDT switch


V+ gnd
| |
* *
* *
* *
servo | | servo
motor motor
* *
* *
* *
| |

 

[gymbo86]

Thanks for the help....