Quick and Dirty FDD extension cable

Update your old 720k to a 1.44 drive etc.
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rubber_jonnie
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Quick and Dirty FDD extension cable

Post by rubber_jonnie » Sun Apr 01, 2018 7:00 pm

As I've largely moved to Gotek these days, it's useful to have an extension to the floppy cable, and unless you've done something like this: viewtopic.php?f=12&t=122, then you'll need to look at options.

One is the quick and dirty option I'll walk through here. I've been using this method for a while, and it's actually pretty reliable and really quite inexpensive.

First off, do a search for "40-pin Male to Female Breadboard Jumper Wires Colourful Ribbon 20cm Cable" to find what you need. I got mine from eBay, but I appreciate not everybody has access, so get it wherever you can. There's 2 important factors. They must be in ribbon cable format, and they must be Male to Female.

This is what I bought:
Jumpers.jpg
Jumpers.jpg (326.47 KiB) Viewed 257 times
The first job is to split the ribbon into 2 pieces, straight down the middle. If you've got 40-pin cable, you now have 2 pieces of 20-pin ribbon cable. Once you've done that, remove 3 wires from one side of each of the 20-pin ribbons you now have, so each one is now a 17-pin ribbon cable.

I removed the same colours from each piece, so I then had 2 pieces of 17-pin ribbon cable with exactly the same ribbon colouring.

Start by taking one piece of 17-pin ribbon cable, and plug the male end into the FDD connector of your Atari ST like so:
CableToCable.jpg
CableToCable.jpg (377.12 KiB) Viewed 257 times

There will be a side of the 17-pin ribbon cable that has an opening, with metal visible. Make sure these aren't facing each other, to avoid the possibility of a short. Also make sure that none of the wires are crossed or twisted, and that they plug into the FDD plug sequentially, or it will make life tricky later on.

Keep going until both 17-pin ribbons are plugged into the FDD cable, as below:
PartWay.jpg
PartWay.jpg (422.41 KiB) Viewed 257 times
Now move on to the FDD, and repeat the exercise with the female connectors of the 17-pin ribbon cable:
CableToFloppy.jpg
CableToFloppy.jpg (486.9 KiB) Viewed 257 times
Again, these should be straight through from the FDD cable, and all the conectors should connect in the same sequence as the ribbon cable (The colours really help here) with no twists at all in the ribbon connectors, as below:
MidWay.jpg
MidWay.jpg (348.13 KiB) Viewed 257 times
Now is the time to double check that all of the connectors run straight through from the FDD connector to the floppy drive or Gotek.

Now, use electronic insulation tape to tightly wrap the bundles of connectors up so that they stay in one place:
WrappingUp.jpg
WrappingUp.jpg (308.48 KiB) Viewed 257 times
You may wish to use the tape at a couple of points along the ribbons to hold everything in place.

Finally, disconnect and you have your extension cable:
Finished.jpg
Finished.jpg (271.58 KiB) Viewed 257 times
Just be aware to handle with care so that once you disconnect, you don't cause any of the connectors to move.

Once it's in place, you'll probably have no need to unplug again, so everything should be fine and dandy.
Collector of old Atari things:
800XL + Ape Warp mod, 2x 1010 cassette, 1050 + Happy mod, 65XE (128k) & XC12, SIO2SD, 2600jr, 7800 and Lynx II
Atari 520ST (1Meg) + Gotek, 1040STFM + Vortex ATOnce + Gotek, 1040STF long button floppy, 4160 STE with Gotek and ROM switcher, 4160STE with 32Mhz booster, ROM switcher and CosmosEx, not to mention various bare ST boards for testing including a PAK 68/2 :)
Plus the rest..
Amiga stuff, Mac stuff, Sinclair stuff etc...
www.electronicnothingness.co.uk

Forgottenmyname
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Re: Quick and Dirty FDD extension cable

Post by Forgottenmyname » Sun Apr 01, 2018 7:12 pm

Good idea, I've used the same cables for the power cable for the ultrasatan inside my Mega.

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exxos
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Re: Quick and Dirty FDD extension cable

Post by exxos » Sun Apr 01, 2018 9:39 pm

Geek points there!

These are the ones I do just for future reference :)

https://www.exxoshost.co.uk/atari/last/storenew/#0065
4MB STFM 1.44 FD- VELOCE+ 020 STE - 4MB STE 32MHz - STFM 16MHz - STM - MEGA ST - Falcon 030 CT60 - Atari 2600 - Atari 7800 - Gigafile - SD Floppy Emulator - PeST - HxC - CosmosEx - Ultrasatan - various clutter

https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxoshost.co.uk/atari/last/storenew/ - All my hardware mods for sale - Please help support by making a purchase.

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rubber_jonnie
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Re: Quick and Dirty FDD extension cable

Post by rubber_jonnie » Mon Apr 02, 2018 10:07 am

exxos wrote:
Sun Apr 01, 2018 9:39 pm
Geek points there!

These are the ones I do just for future reference :)

https://www.exxoshost.co.uk/atari/last/storenew/#0065
Aye, yours are much, much nicer it has to be said :thumbup:

Do I get a voucher or something if I get enough geek :ugeek: points?
Collector of old Atari things:
800XL + Ape Warp mod, 2x 1010 cassette, 1050 + Happy mod, 65XE (128k) & XC12, SIO2SD, 2600jr, 7800 and Lynx II
Atari 520ST (1Meg) + Gotek, 1040STFM + Vortex ATOnce + Gotek, 1040STF long button floppy, 4160 STE with Gotek and ROM switcher, 4160STE with 32Mhz booster, ROM switcher and CosmosEx, not to mention various bare ST boards for testing including a PAK 68/2 :)
Plus the rest..
Amiga stuff, Mac stuff, Sinclair stuff etc...
www.electronicnothingness.co.uk

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exxos
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Re: Quick and Dirty FDD extension cable

Post by exxos » Mon Apr 02, 2018 10:29 am

rubber_jonnie wrote:
Mon Apr 02, 2018 10:07 am
Do I get a voucher or something if I get enough geek :ugeek: points?
You get more work to do ;)
4MB STFM 1.44 FD- VELOCE+ 020 STE - 4MB STE 32MHz - STFM 16MHz - STM - MEGA ST - Falcon 030 CT60 - Atari 2600 - Atari 7800 - Gigafile - SD Floppy Emulator - PeST - HxC - CosmosEx - Ultrasatan - various clutter

https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxoshost.co.uk/atari/last/storenew/ - All my hardware mods for sale - Please help support by making a purchase.

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rubber_jonnie
Posts: 347
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Re: Quick and Dirty FDD extension cable

Post by rubber_jonnie » Mon Apr 02, 2018 10:41 am

exxos wrote:
Mon Apr 02, 2018 10:29 am
rubber_jonnie wrote:
Mon Apr 02, 2018 10:07 am
Do I get a voucher or something if I get enough geek :ugeek: points?
You get more work to do ;)
Ok, fair enough, better get working on earning more points then!
Collector of old Atari things:
800XL + Ape Warp mod, 2x 1010 cassette, 1050 + Happy mod, 65XE (128k) & XC12, SIO2SD, 2600jr, 7800 and Lynx II
Atari 520ST (1Meg) + Gotek, 1040STFM + Vortex ATOnce + Gotek, 1040STF long button floppy, 4160 STE with Gotek and ROM switcher, 4160STE with 32Mhz booster, ROM switcher and CosmosEx, not to mention various bare ST boards for testing including a PAK 68/2 :)
Plus the rest..
Amiga stuff, Mac stuff, Sinclair stuff etc...
www.electronicnothingness.co.uk

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