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TandyisDandy
April 22nd, 2010, 02:48 PM
Has anyone ever tried the famous Ivan Baggett fix for using a modern floppy? It says that pins 1,2,4 and 5 on the CN401 should connect to +5 but where does the +5 connect on the standard floppy end? Where is that +5 going?

And what about the power connector itself? A modern floppy's power connector has four pins but the stock tandy floppy only has 2.

Anybody actually try this set up?

Unknown_K
April 22nd, 2010, 04:21 PM
On the standard floppy are all 4 pins in the power connector needed?

TandyisDandy
April 22nd, 2010, 06:53 PM
I don't know. I also don't understanding how the +5 is connected to anything on the floppy. The table shows +5 from the tandy power connector designed for a floppy goes to several pins on the flat flex connector through the CN401 but then what does that do? It doesn't say to hook any of that up to the kludged modern floppy cable. If the original 2 pin floppy power is going to be hooked directly up to the new floppy power (and that's an assumption, but a reasonable one) and just ignore what would normally be the +12 pin on the new floppy , what's the point of original pins 1, 2, 4, and 5from the flat flex going to the 5 volt hot and not to the floppy? Is that feeding something back down to the motherboard or what? So... I've got the parts, but I don't want to start the project until I know where I'm going. Of course, I could also have it all wrong.

Chuck(G)
April 22nd, 2010, 07:05 PM
On the standard floppy are all 4 pins in the power connector needed?

On most 3.5" floppies of recent (meaning since about 1988) manufacture, only the +5 supply line is used. Most 5.25" floppies use +12 and +5; 8" drives commonly use +24, +5 and +12 (and sometimes -5) as well as AC line voltage for the motor (there are 8" drives with DC motors, but they're less common).

I wonder if your 1100 FD doesn't use the standard 26-conductor Teac FD-05 pinout (which includes power).

TandyisDandy
April 22nd, 2010, 09:21 PM
On most 3.5" floppies of recent (meaning since about 1988) manufacture, only the +5 supply line is used. Most 5.25" floppies use +12 and +5; 8" drives commonly use +24, +5 and +12 (and sometimes -5) as well as AC line voltage for the motor (there are 8" drives with DC motors, but they're less common).

I wonder if your 1100 FD doesn't use the standard 26-conductor Teac FD-05 pinout (which includes power).

No it is 24 pins and is in the flexible flat cable form.

Chuck(G)
April 22nd, 2010, 09:39 PM
No it is 24 pins and is in the flexible flat cable form.

So is the FD-05's connector (flat mylar goes into a connector that just clamps the bare cable), but 26 pins and it doesn't match the 1100FD's connector.

TandyisDandy
April 22nd, 2010, 11:47 PM
There's a pin out in the project pdf. The path of that +5 just doesn't make sense to poor old me. Bearing in mind I haven't done a lot of this kind of work since the days when that computer was new. :)

TandyisDandy
May 6th, 2010, 09:22 PM
There's an awful lot of people who have posted in various forums about this fix over the years, nobody has actually tried it?

TandyUser
March 11th, 2012, 07:23 PM
I will pay $20 for this adapter in working condition that allows you to put in an off the shelf floppy in a tandy 1100fd. I'm beginning to think it is more myth.