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View Full Version : ST-225 - Red/Green Led's



TomFCS
December 6th, 2008, 07:17 PM
I was just wondering if the difference in color of the drive activity led's on these drives has any special significance? Earlier/later manufacture date, slightly different specs, where it was manufactured, etc... Just curious.

Druid6900
December 6th, 2008, 07:37 PM
Well, I have two working 225s sitting here, one with a date code of 8823 which has a green LED and one with a date code of 8652 which has a red LED.

I'm GUESSING that the earlier ones had a red LED to match the floppy drives LEDs on the XT's 360K drives while the later ones had the green LED to match the 1.2M's green LED.

modem7
December 7th, 2008, 01:49 PM
In the ST-225 of a friend's IBM 5162, the LED is yellow (which matches the LED in the floppy drives).

TomFCS
December 7th, 2008, 02:23 PM
This never even occurred to me and it does seems like pretty good reasoning that they should match the floppy. I don't think I've seen a yellow one myself, kind of wish I had one now though. Are the date codes the ones located on the underside of the drive near the spindle cover or are they elsewhere? I'm a little confused by which numbers I should be looking at here. Seems like they may be stamped/etched in different places.

http://www.welook4things.com/ebay/st-225_date_01.jpg

modem7
December 7th, 2008, 03:15 PM
Are the date codes the ones located on the underside of the drive near the spindle cover or are they elsewhere? I'm a little confused by which numbers I should be looking at here. Seems like they may be stamped/etched in different places.
What I assume you are looking for is a date of assembly. Maybe the ST-225 doesn't have that recorded on it. The date of manufacture of various components should be a good indicator though, given the quantities that ST-225 batches would have been made in. You'll notice that the word "Date" appears on the sticker on the ST-225 stepper motor (top-left of the picture). So the accompanying stamped date is the date that the stepper motor was made. Many of the ICs on the circuit board will have a week-of-manufacture (format of YYWW) stamped on them. On my two ST225s, the year on the stepper motor matches that on the ICs. So I think, given the quantities that ST-225 batches would have been made in, that you can reasonably assume that the year of manufacture of your ST-225 will either be the year stamped on the stepper motor, or the following year.

Chuck(G)
December 7th, 2008, 03:57 PM
You can similarly find Teac FD55GF 5.25" floppy drives with green and red LEDs. It might be that the green LED was preferred on later equipment as red came to be used as an error indicator.

Just a guess...

Druid6900
December 7th, 2008, 07:36 PM
This never even occurred to me and it does seems like pretty good reasoning that they should match the floppy. I don't think I've seen a yellow one myself, kind of wish I had one now though. Are the date codes the ones located on the underside of the drive near the spindle cover or are they elsewhere? I'm a little confused by which numbers I should be looking at here. Seems like they may be stamped/etched in different places.



On mine, when you have it rightsideup, the date code is stamped on the front left side of the unit. That's the "test & ship date"

Terry Yager
December 7th, 2008, 09:10 PM
Then there are the Compaq 'Dual-Mode' 5.25" floppy drives which have LEDs that shine green or red, depending on which density the installed disk is...

--T