Dolch Pac 65 - Repair and fit out - Page 1
Forum section: electronics / general

author: Tony_G
author_rank: Super Contributor
timestamp: March 02, 2018, 04:17:53 pm
content: Hey All,Just picked up a reasonably good condition Dolch PAC 65:and here is the shocking Win95 desktop:The only major issue with it right now is the floppy drive has died.Next steps for the unit are:Fix floppy driveUpgrade to SSD driveReplace Adaptec networking card with comething supported in XPIncrease the memory to the max 512MBAdd a NI PCI-GPIB+ cardAdd a HP 82324A MEasurement CoprocessorCheck out the backlighting (Curious Marc did a vid on fixing his)Anyway, will paste back here as I work on it. Final goal is to have a dual boot, DOS/WinXP machine capable of running old HP Series 200/300 programs, DOS based HPIB apps or Windows based ones in a smaller form factor than the large desktop tower I have now. I envisage this as something that I can keep out of the way either under the desk or in the storage cupboard and pull out as needed without taking up all the bench space.TonyG

author: Ampera
author_rank: Super Contributor
timestamp: March 02, 2018, 06:13:29 pm
content: I'd suggest Windows 2000 instead of Windows XP. Has most of the same application support, possibly better hardware support, but most importantly, won't completely stall out on a Pentium 2 350 Mhz.Just a suggestion.

author: Tony_G
author_rank: Super Contributor
timestamp: March 02, 2018, 06:55:23 pm
content: Thanks. I'll keep that in mind as I was also thinking of upping the CPU as well but thought I'd give it a try first. From what I can find on the web w.r.t the CI6BM motherboard I should be able to get a PIII 600 in there.TonyG

author: Tony_G
author_rank: Super Contributor
timestamp: March 08, 2018, 04:13:30 am
content: Well my weekend and this week so far ended up being a bit of a goat rodeo so I didn't get much done.However what is has allowed is for some more of the bits to arrive.I fixed the floppy drive with the guts of a USB floppy but I really missed having the face plate so I bought another one of the exact model to replace itPCI Network card to replace the Adaptec one512MB (2 x 256MB sticks) MemoryOriginal NI PCI-GPIB+ cardHP 82324A Measurement Coprocessor with 2MB ramCompact Flash adapter & Cards - 2 x 16Gb for DOS+Win3.11 and Win98SE - 1 x 64GB for WinXPReplacement CD ROM drive as it too was failingOne thing you'll notice is that I've changed from an SSD to a CF Card - Turns out the SSD was much more problematic than expected and the CF card IDE Drive replacement is what most people in the Industrial Control space do to prolong the lives of the machines in their production hardware. I'm still waiting for the bracket to arrive so I can attach the CF to IDE adapter to a slot rather than mount it in the drive bay. I'm going to do this so I can swap the CF Cards and not have to worry about dual booting.As I wanted to make sure that that the 82324A was working, I actually just dropped this in - Here is it just fitting into the ISA slot and machine back (the top of the card has about a 1-2mm gap between it and the shield that goes over it:and here it is running HP Basic on the 68K measurement coprocessor:Hopefully I'll be able to get to this again on the weekend for a vide.TonyG

author: Tony_G
author_rank: Super Contributor
timestamp: March 14, 2018, 05:58:08 am
content: I've posted the first 3 videos on my channel.It didn't go so straight forward.https://youtu.be/LCC8Uvdyhpchttps://youtu.be/AnevCK59dPUTonyG

author: Tony_G
author_rank: Super Contributor
timestamp: March 18, 2018, 06:34:12 pm
content: And the last 3 parts have posted - switched over to a compact flash adapter and registered memory. Both the NI PCI-GPIB and the HP 82324A work correctly.https://youtu.be/baVIJoJSCWwhttps://youtu.be/KixjOhNkqAYhttps://youtu.be/YgcXszF-4XYTonyG

author: CNe7532294
author_rank: Regular Contributor
timestamp: March 20, 2018, 05:45:04 am
content: Hello all, I've messaged this on Tony_G's youtube and I might as well mention this here too. I'm hoping to get CuriousMarc's attention on this as well. I essentially found a flaw with the floppy/cd drive area. Mainly the floppy. Could have an effect on the CD, I haven't confirmed. The flaw has to do with the ribbon cable of the floppy and the ribbon connector of the IDE/power to ribbon cable PCB adapter.In the following pictures you'll see that the adapter is flipped upside down and close to the chassis. Its so close that if you so much as overtighten the nuts holding the adapter down, the ribbon cable could come into contact with the chassis. Also the flex on the ribbon cable matters as well.What is happening here is that the ribbon cable's pins are not fully inside the connector. They are partially exposed! Sandwiched between the connector and chassis, the power rails and the data rails will have no problem with a short to groundresulting in a blown power rail (what happened to me and the best case imo) or data pins going low causing data corruption (worse case if your are reading/writing)Post repair. Hard to see but what you see on the floppy side is about what you see on the adapter side. Solution to problem pictured.During repair. I had to desolder the connector and repair the trace, cutting out pieces of copper and soldering them. Kinda lucked out.https://flic.kr/s/aHsmejnZL8Album where I have pictures stored. I apologize for the less than ideal pictures. I didn't have the forsight nor the time to snapshot during repair.Now in some cases if its not disturbed (ie. moved around when powered on) you could have a functional floppy drive. I believe that is what is happening here when the drive was replaced or in Marc's cautious care. However, you'll still run the risk of breaking this area if you don't properly fix this problem. That or a seller/another end user can power the unit not knowing any better.The solutionI did was cheap and easy (maybe not the most long time solution if something eats at it).I basically put an orange sticky note as an insulator. A proper long term solution would be to get thesame type of insulating plastic you see all over the caseinside. Just be careful tightening the adapter back into place.Back to the videos, one of the questions I'd like to ask is where did you get the replacement CD drive? I searched before but couldn't find any. Maybe I'm not searching right?

author: nidlaX
author_rank: Frequent Contributor
timestamp: March 20, 2018, 08:43:40 am
content: I'll just leave this here: if you need some PAC 65 parts for any reason, I can probably dig some up and send it to you for close to the cost of shipping.

author: Tony_G
author_rank: Super Contributor
timestamp: March 20, 2018, 01:43:22 pm
content: First up thanks for the warning about the drive cable - I had shot the video before I saw your comment so I haven't fixed it yet. I do have an extra CF to IDE adapter now so I was planning on dropping that into the unit so I can have a permanent "D" to share data between swaps of the main CF card.Quote from: CNe7532294 on March 20, 2018, 05:45:04 amThe problem might be that there were a few CD drive models used. The one in my machine was a Teac CD-224E and there is a good selection of them on eBay between $10-20. As far as I can tell the model comes configured with either Master or Slave so be prepared to move it to the secondary IDE port. So are probably setup for cable select or othe schemes - I could only find the datasheet for the R83/R93 variants but it explained the M/S setup in there so I assume it applies to my variant as well.TonyG