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Trouble Creating P70 Reference Diskette

M

mahunt

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Joined
Mar 25, 2024
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8
Hi everyone.

I'm trying to resurrect a P70 and I need to recreate the reference diskette.

I downloaded the zip file from this site, installed the WinImage program and I always get either one or multiple "Disk error on track X, head 1, etc." Is there a trick to doing this?

I'm using a Dell computer running Win 11 Pro and a USB floppy that works perfectly well.

I've inserted, read, formatted about 10 floppies and they work fine with Windows 11, but I just can't seem to get a good reference disk without the error.

Any ideas?

Thanks.
 
Thanks for the reply.

I have been running WinImage as Administrator, but something else happened.

The old adage that as soon as you ask for help with something, that something starts working. WinImage ran without an error message, so I think I may have a good P70 Reference diskette now.

Now I just need to verify that the P70 diskette drive is functioning.

When booting, I get the 2 errors for battery and date. With the diskette in the drive, the drive light comes on, you can hear the drive "stroke" the diskette, but nothing happens.

I did a preliminary removal of the diskette drive when I decided to resurrect the P70 a few days ago. Pretty tough to remove little sucker, but everything was amazingly clean. No dust to speak of. PCB traces looked pristine, no leaky caps.

I don't suppose anyone offers a diskette rebuild service for these drives. I'm OK recapping big stuff like a turntable or an amp, but the form factor of the diskette drive AND its components are pretty small, plus I stopped disassembly on the board that is captured by the flywheel.

Any suggestions?
 
It's been quite a few years since I made my reference disks. From what I recall, it was NOT going to happen with a modern 3.5" USB drive.
I have an in-between PC with real 5.25 and 3.5 drives and had to use that. Also, after you create the reference disk, do not try to view the directory under Windows. If you do, the disk will become corrupt and no longer work.
I used the RFP70A.EXE file from this site and it worked great.

As far as your 3.5" drives, 99% chance the capacitors will need to be replaced. For my systems, I bought new 3.5" drives and reconfigured the cables that came with them. They fit perfectly and at that time were only $4 bucks on Amazon.
 
It's been about 7 years since I converted them, so I don't remember all the details.

I bought Memorex drives from Amazon for $4 and they included ribbon cables. I removed the face-plates from the new drives and installed them in the P70 housings. I don't think I had to adapt or modify anything to get them to fit.

I modified the new cables using this as a guide:

If you don't want to modify a cable, this appears to be a good option:
zzxio.com

34-pin floppy disk adapter for IBM PS/1 and PS/2 - ZZXIO

This converter allows IBM PS/1 and PS/2 computers to use standard floppy drives. These models of IBM computers have the power provided over the 34-pin connector, which will fry a "modern" floppy drive. This adapter routes the power out of the 34-pin connector into a traditional 4-pin Berg...
zzxio.com zzxio.com

At the time, it was actually cheaper to order brand new drives from Amazon with free shipping vs. new capacitors +shipping from places like Mouser. And I still have my old drives and their original cables if I decide to repair and go back to stock.

Only thing different is the white eject button instead of blue.

ckit4.jpg
 
I guess a few photos of the portable would be OK.

I have a history with this machine as I supported it during it's professional career back in the day. I ended up keeping it for a small sum, which was a bargain over it's original price. I may still have the original paperwork somewhere, but I'd like to get it configured first.

IMGP5648.JPG

Desktop Sales 8M memory expansion card and a 3 Com Ethernet with an AUI RJ45 adapter. 8Mb on the system board, Cyrix 486 CPU with matching math coprocessor. The fan is a little cleaner now. 120Mb hard drive with WFWG, soon to be Win95. If I can't find the reference disks for the 2 cards, I will get a sound card.

Torch, I like the clean look of your floppy modification. I think I will go in that direction.
 
I had that same ram card. Dont know what happened to it as its been over 15 years since I have seen it.

Ohhh 🤮 Dont put windows 95 on it. It will crawl! Its essentially a 386 bus regardless of the cyrix cpu! Windows 95 came out 7 years after this machine was released.
 
I can't remember if the RAM card needed a reference file. Although the P70 isn't configured yet, it does count up the 8M before issuing the 2 config errors. Do the extra RAM kick in via a DOS config file? It's been longer than 15 years for me.

A 32 bit 20Mhz bus, slow yes, but the same width as a 486 bus. What about running OS/2?
 
Torch said:
As far as your 3.5" drives, 99% chance the capacitors will need to be replaced. For my systems, I bought new 3.5" drives and reconfigured the cables that came with them. They fit perfectly and at that time were only $4 bucks on Amazon.
Click to expand...
Adding to that, I cannot remember if it was the Alps or Mitsumi drives but the media and write protect sense switches have occasionally gone bad with dirty or oxidized contacts. The drive then acts like even with a known good floppy and a recapped drive as if you never inserted a disk. A continuity check can test this and usually contact cleaner can remedy it.
 
Maybe the RAM card will kick in after I clear the 2 config errors.

I will still need the 3 Comm card to be added to the reference disk.
 
The only success I've had adding ADF's to the reference diskette was to do so AFTER the system was configured and booting, THEN transfer the ADF to the local machine and purely under DOS, copy it over to the diskette.
 
Its definitely caps if its not reading. Mine was reading one year ago on its original caps, then in the past month or two when I started my other thread the drive stopped reading. I have read enough other p70 related topics to know its a 100% MUST at this point. Dont replace the drive, just at the very least replace the two polarized electrolytic caps. I did this and my drive worked. I did not have the other 3 bipolar caps so I ordered them. The drive was working fine but I replaced them when they came in. At the very least replace the two caps and your drive will work again. I mean its two caps, washing your dinner plate is more effort than two caps... just do it.
 
Thanks, I know about the ADF files and the need to resolve the 2 config errors first. I first need a working floppy drive and a good reference disk.

I removed the drive from the P70, located the tiny caps (and the polarity of 3), but couldn't see how to remove the flywheel to access the underside of the PCB.

I have experience with a soldering pen as I've recapped 2 B&O linear tracking turntables and a Yamaha M70 amp. I've also done some work on some suspension computers on my car.
 
Why would you need to access the underside of the drive PCB when they are SMD caps? Dont do it.
 
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