1050XL 3.5 floppy

[hueyjones70]

After putting together a couple of Dropcheck's XF551 boards, I decided to see if I could make use of the old PCBs and with a little cutting I was able to fit a XF551 pcb and a 3.5 mechanism into a 1050XL case. The back of the case had to have a large rectangular cut out and that is the only bad cosmetic issue.  I would like to use the 1050 power switch and power on LED. I have several non-working 1050s so I think I can cut off the pcb section that has the switch and LED; that leaves wiring the front switch as my only real challenge. I would like to know if I could leave the 551 switch in place in the off position and run wires from the power jack through the 1050 switch to the back of the 551 switch.

[_The Doctor__]

any reason not to repair the 1050's? US doubler/happy/bit writer 1050's are quite nice. It would be easier to just run wires and switches then hacking and cutting up PCB's. Musical chairs in play. Easy to make/get/print cases these days also. Folks might be able to help if need be.

[hueyjones70]

I have 3 or 4 1050s that I haven't been able to repair, I have paired working mechs with PCBs and working PCBs with different mechs. I have cleaned heads, lubed rails, checked voltages on test points and examined PCBs for broken traces and solder joints around the SIO ports. I would try replacing some ICs if I had any troubleshooting guidelines but there doesn't seem to be a wealth of advice on the forums for disk drive repair. I am not going to do this with any more because it is a lot of work. I just wanted to do one so I would have a really unique item. When I get the wiring figured out I will post pictures of the process.

[+mytek]

1 hour ago, hueyjones70 said:

I have 3 or 4 1050s that I haven't been able to repair, I have paired working mechs with PCBs and working PCBs with different mechs. I have cleaned heads, lubed rails, checked voltages on test points and examined PCBs for broken traces and solder joints around the SIO ports. I would try replacing some ICs if I had any troubleshooting guidelines but there doesn't seem to be a wealth of advice on the forums for disk drive repair. I am not going to do this with any more because it is a lot of work. I just wanted to do one so I would have a really unique item. When I get the wiring figured out I will post pictures of the process.

Be sure to save one of those dead 1050s for a 1088XLD ? .

 

Any pics on your project?

 

[Dropcheck]

MacRorie and I are working on a limited run of 3.5" floppy drives XF551 based circuitry in a 1050 case.  Essentially a 1050 case shaped XF551 dropin pcb with a modified holder for the 3.5 drive.  It will use the original 1050 power jack, DriveID and power switch.  At this point we don't think there will be any case mods needed.  We hope to have fully assembled units available for when the 1088XLD is released.  MacRorie may decided to do it in kit form too.  I'm not sure.  We'll have more details in a month or so, once we are done with the fit tests etc. 

 

I doubt we'll be producing a 5.25" drive version.  In most cases that would require some case modding, which neither one of us wants to take on for anything other than a one off.  And I for one don't want to do that either. 

 

Just to tease a little:

 

Edited August 2, 2019 by Dropcheck

[manterola]

That is great news, !!!   Another "product" could be (here I go again, so keep tight....)  a 1050 inspired or replica case (a 3D printed small 1050 case), which fit the sf551 existent PCB with a standard 3.5 floppy drive (with black faceplate which are very common and easy to get).

The case should be something like this...

https://www.thingiverse.com/thing:3287420

 

[hueyjones70]

I like both of those projects.

Edited August 2, 2019 by hueyjones70
Duplicate of previous reply

[toddtmw]

@mrrobot, any chance you would consider doing a 3-d model of the full-sized 1050 plastic and releasing under CC to allow projects like this to have an enclosure that could be "modded" without using Dremel?

 

You've made great progress on your modelling skills and you certainly have the talent for it. There is actually already a 1050 face plate out there. Just need a top and bottom shell and *BAM* 1050!

[hueyjones70]

How much would it cost to have a 1050 or a 551 case 3D printed?

[+Nezgar]

On 8/1/2019 at 11:52 AM, hueyjones70 said:

I have 3 or 4 1050s that I haven't been able to repair, I have paired working mechs with PCBs and working PCBs with different mechs. I have cleaned heads, lubed rails, checked voltages on test points and examined PCBs for broken traces and solder joints around the SIO ports. I would try replacing some ICs if I had any troubleshooting guidelines but there doesn't seem to be a wealth of advice on the forums for disk drive repair.

As for troubleshooting, first you need to determine if there is any serial communication with the computer working... With the drive set to Drive 1, turn on the drive - watch for the normal head seek out then in to track 0. Turn on the computer. If it starts printing BOOT ERRORs, then the drive controller SIO commands are working... and the CPU, RAM, RIOT, ROM are probably good.

 

If still nothing, I'd start by testing each of the 5 main IC's across the middle of the PCB one at a time in a known working unit. The 6810 RAM has been the most often faulty chip for me. Then also test the 6532 (RIOT), CPU, ROM. The WDC controller chip would be last... and if you do swap it - be VERY sure to put the chip back in the drive it came in, as each 1050 PCB is fine tuned to the WDC chip, and re-calibrating those adjustments is pretty much impossible without an oscilloscope, and if needed, read of this thread:

If swapping the IC's still is not working, then its time to dive into checking voltage regulators, capacitors, etc.

 

EDIT: When swapping the ROM - ensure the JP1/2/3/4 configurations are the same between both drives. (2732 EPROM / 2332 Mask ROM selector)