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.
 

Fizzbinn

Well-known member
Looking to source an LED for my Quadra 700 (and Iici)'s hard disk drive activity light, something period appropriate. From above it sounds like it is supposed to be an amber color?

I'm not sure what the secret googlesse is to find this type of LED either....

Right now I'm thinking this might be close:
https://www.amazon.com/gp/product/B077X9WSLX/ref=ox_sc_act_title_1?smid=A3S1JN3RP90N86&th=1

The LED itself looks too yellow, but there picture of the light produced looks Amber-ish.

Any advice, guidance would be appreciated!
 

Mk.558

Well-known member
Sanitized Amazon link: https://www.amazon.com/gp/product/B077X9WSLX

Phipli is correct. Most were amber. SEs were notable mostly for being red, but it depends on if you got larger HDD later and included LED with it. My IIci has green, the SE/30 is red, but the bracket has it built into it.

The technical term for these LEDs, if they are round, normal dome LEDs is T1-3/4 LEDs. T1 LEDs are 3mm in diameter (not the bottom ring) and T1-3/4 LEDs are 5mm.


You'll find just about every common type of LED at most electronics distributors. If you change the color, like white or blue, those want a higher forward voltage and may or may not draw more current.
 
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