Question for my course work (mac related)

[martdaman]

Hi,

I do electronics for one of my subjects in school (year 11) and i have decided on designing and making a 200 watt amplifier for my emac. But what i need to know is the specification on the headphone jack, i ve looked on the specification on apple.com but it just says headphone jack 3mm. so can anyone help me?

Thanks Martin

P.S. if you want i will post pictures of the amplifier after its been made. It going to be white plastic same as my emac, i will call it iAmplifier

 

[ToddW]

the 3.5mm audio jack that you will use to hook up to the output of the emac is standard. It has a type of pinout for the left and right channel and signal ground. I forget the pinout, but it should be the same for all 3.5mm audio jacks. Your circuit is going to be simple enough. I would look for some audio type op-amps for your circuit. Should relatively simple and fun. All the parts you should be able to get form radio shack or an online catalog place like digikey.com

Edit:

This circuit looks promising:

http://www.mif.pg.gda.pl/homepages/tom/files/simp200W.gif

 

[Blue Velvet]

This is what you want:

The headphone jack has the following electrical characteristics:
• output impedance: 5.0 ohms (nominal)
• maximum level: 1.5 Vrms (4.2 V peak-to-peak)

Headphones should have an impedance not lower than the recommended minimum impedance of 32 ohms. Headphones with lower impedance can be used, but with some degradation in performance.

Sound Specifications
The frequency response of the sound circuits, not including the microphone and speakers, is within plus 1 dB or minus 3 dB from 20 Hz to 20 kHz.

All from here:
http://developer.apple.com/documentation/Hardware/Developer_Notes/Macintosh_CPUs-G4/eMac/index.html

 

[martdaman]

Thanks

Thats is great infomation from both of you, my teacher will be pleased lol

Thanks!

 

[martdaman]

200 watt output

can anyone tell me the out put of that 200 watt amplifier

Thanks Martin.