Floppy drive controller board removal

[Mochatea396]

Greetings fellow members,
I’ve just purchased my first TRS80 model 3. 48k RAM and a really clean machine. The PSUs are Astec AA11320s. I replaced the .1uf 250V X safety capacitors with .1uf 250V X2. I read a post here that X2s are fine to use. Please interject if this is wrong. The reason for my post is I’m removing the drives to clean the heads and the head rails and I’m used to seeing screws attach the drive controller board. Not here though. How do I remove these?
Thanks group

 

[ldkraemer]

I've seen that type of fastener on the Floppy Drive Logic boards before. Look real close at
the fastener, as it has a center pin that is pressed down to spread the end of the fastener,
which holds the Logic Board in place. You will need to get under the fastener and somehow
easily force that center pin back up towards the PCB so the fastener will release the Logic
Board.

What is the Manufacture name and Model Number of the Floppy Drive(s)? It doesn't appear to
be a Tandon TM-100 Series, or a Texas Peripheral Incorporated Drive (clone of a TM-100).
If it is a Tandon TM-100 Floppy Drive, make sure you remove the RPM Board on the back
of the Drive, and check the two 16Volt 47uF Caps to see if they have leaked their acid on the
PCB traces. If so, the PCB traces are likely gone, and the RPM Board will need to be rebuilt,
then tested for 300 RPM. I use Copper (hollow) rivets to do that, as it makes the repair a lot nicer.

I use Alcohol to wipe down the Guide Rods that the head carriage assembly rides on, the about
three drops of Dri-Slide (A Motorcycle Cable Lubricant which does not attract dirt) to lubricate
the Guide Rods. This will last for years, and make your Floppy step quietly. It also works good
on Flat Bed Scanners. Dri-Slide can be purchased from any local Motorcycle shop, or Amazon.

If it is a Tandon TM-100 Drive be sure to check the Center Pin of the Door Hinge. It needs to be a
full length Brass Rod, versus two short White Nylon Pins. If you see two short White Nylon Pins,
they need to be replaced with a Full Length Brass Rod. Be sure to look at the Hinge Part making
sure it does not have a broken end. If the Hinge part is broken, there are Resin Printed replacements
available.


Larry

 

[Mochatea396]

Thanks for all that Larry,
I don’t physically have the drive removed yet but they have the brass rod on the doors. I don’t see any board on the back of either drive. Looking closely at those fasteners I see it does look like a pin in the center. The drive will have to be removed I see to access the fastener on the left. Hopefully I have something I can use to try and push the pin up. When I have the drive out I’ll post a few pics so you can see what type it is.

 

[ldkraemer]

Sure, and post the Manufacture's name and Model of the Floppy Drive.

You might be able to use a small Pocket screwdriver, with the flat part of the blade against the Plastic Pin.
I've removed a couple that way. I wouldn't try driving it on through an likely it won't have enough room
to be removed.

Larry

 

[Mochatea396]

Hi Larry,
Ok, your help was priceless. Would have never figured that out. They are tough, I found pushing it up as far as it will go, then grab the pin gently with side cutters and rock it and the whole thing pulls out. Going back in I couldn’t really press the pin back down so I laid a flat screwdriver blade on the top and gently tapped it back down. Cleaned everything did good and on to the second drive. These drives are in fact Texas Peripherals the only number I see is 10-5355-001.

 

[ldkraemer]

Yes, I've located the Information on the Texas Peripheral Incorporated Floppy Drive with
the number 10-5355-001 in the Aluminum Frame. It appears to be a Single Sided, Double
Density, 40 Track, Floppy Drive. You will probably want to download this information and
save it for the future.

Larry

 

[Mochatea396]

Thanks again Larry,
I will definitely hold on to them. I’ve got both drives cleaned really good, boards back on ready to go back. I’m waiting for capacitors, I want to recap the PSUs while I’m in here.