• Updated 2023-07-12: Hello, Guest! Welcome back, and be sure to check out this follow-up post about our outage a week or so ago.

Quadra 700 HDD LED Specs?

Jakeys

Member
Hey all! I've recently picked up a mostly working Quadra 700 I'm looking to restore. No audio but I suspect capacitor C23 near the DFAC chip is bad, and one of the ADB ports is not working while the other works but there is no caps lock light on any keyboard. Otherwise, decent shape and running well.

However, the hard drive activity LED is missing from the light pipe and I'd like to make a replacement. The problem is just that I'm not sure what colour or brightness I'm meant to go for. I looked for videos to get a sense of how bright it is, and I found a couple where it looks like it might be green. I would have assumed it should be amber.

Can anyone with a Quadra 700 or similar enclosure Mac let me know what colour your HDD activity LED is, and how bright it is in relation to the power LED? Extra bonus points if anyone has a spec sheet or did a similar replacement and can provide details so I can buy another one.
 

Phipli

Well-known member
Hey all! I've recently picked up a mostly working Quadra 700 I'm looking to restore. No audio but I suspect capacitor C23 near the DFAC chip is bad, and one of the ADB ports is not working while the other works but there is no caps lock light on any keyboard. Otherwise, decent shape and running well.

However, the hard drive activity LED is missing from the light pipe and I'd like to make a replacement. The problem is just that I'm not sure what colour or brightness I'm meant to go for. I looked for videos to get a sense of how bright it is, and I found a couple where it looks like it might be green. I would have assumed it should be amber.

Can anyone with a Quadra 700 or similar enclosure Mac let me know what colour your HDD activity LED is, and how bright it is in relation to the power LED? Extra bonus points if anyone has a spec sheet or did a similar replacement and can provide details so I can buy another one.
All disk activity lights on macs, other than a few early SEs and possibly IIs, were amber. Brightness... normal 1980s amber LED :)

Usually the current limiting resistor is in the actual hard disk - you don't need to add one, but when I replace the disk LED with a modern one I usually add a resistor because modern ones are so much brighter.

I'd say use a modern amber LED and stick a 1k resistor in line with it and see if it matches the brightness of the green power LED.

Unhelpfully I've replaced both LEDs in my IIci - it has a purple disk activity light and a colour cycling LED for power :p

 

Phipli

Well-known member
See if you can find these wires on your local amazon - they're handy because they have 2mm connectors on one end, which are perfect for more modern SCSI disks (and surprisingly difficult to buy). Older disks more likely use the more conventional 2.54mm LED connector.


To make hard disk LEDs on wires for later SCSI drives I cut one of those wires to length, cut most of the +ve lead off the LED and replace it with a resistor, put a bit of heatshrink over the resistor to isolate it from the other leg, solder the resistor+LED onto the end of the cut wire, then heatshrink over the join.
 
Top