At 02:40 PM 2/4/06 -0800, you wrote: Yes. No. They're ALL the same tapes and there are only two different models of tapes drives (but both are very similar and have the same drive wheel problem). Chances of reading original tapes at all are less than 50-50 in my experience. First, fix the tape drive and test it with a sacrifical tape. Once you KNOW it works*, format a couple of tapes to store the files on (or better yet, hook up a disk drive and save them on disks) then try to read your original tape. Read a file then immediately save it. Repeat until you've saved all the files. Don't play around and try to run the files, read other files or anything else. The chances that you'll be able to read a file a second time are SLIM. I once experimented with 13 or 14 HP tapes (ones that all had good drive bands in them). At least four of them failed within 2 to 3 reads! A few lasted for about 10 or 12 reads (that's about enough to read all the files on a typical tape). Only three lasted longer and only one lasted till the end of the first day and it failed within 3 or 4 days. MANY HP tapes fail to read even once due to bad drive bands, in fact I'd say most of them have that problem. You can replace the drive belt with one from a newer tape but it's a PITA and I've never had much luck with it. But I know others that say that they can replace them and they work ok so I must be doing something wrong. BUT even if you overcome the drive belt problem, the tape will almost cetainly shed the magnetic media and you won't be able to read anything beyond that point since it sees the media-less tapes as an End-Of-Tape hole. VP's webpage has some excellant pictures of these problems at <http://www.series80.org/Articles/capstan-repair.html>. If anyone gets Gung-Ho and gets properly setup and wants to spend some time recovering files I have a LOT of original HP tapes with HP software. *Oh yeah, FYI the tape drives will work even if the capstan isn't exactly the right size. That is it will write and read tapes formatted in it but it won't be able to read original HP tapes or tapes written in another machine. IIRC the capstan has to be +/- .008" for it to read properly. It's been a long time since I worked on the HP-85 drives and I gave away all my notes but >IIRC< the correct size for the capstan is 0.421" But I may be completely wrong about that. I'm sure some of you have experimented with repairing the drives and you realize that your heat shrink tubing, surgical tubing or whatever you're using only comes in certain thicknesses so it's difficult to get the capstan the exact size that you want. But here's a little secret that I used to use. I would repair the capstan then measure it's o.d. If it was too small then I'd take the tubing off and wrap the capstan with thin cellopane tape. Cut the end so that it matches up with the beginning of the tape and doesn't leave a lump. You can even cut the beginning and end at an angle to minimize any lump. The tape that I used was 0.001" thick so each layer was 0.002" thick (2 sides of the capstan remember). I put on enough layers to exactly make up the difference between the measured o.d. and the desired o.d. When I was rebuilding drives I kept the final size to within +/- 0.001" and EVERY drive that I sent out worked fine. The materials that we're working with aren't entirely consistant and the results aren't always predictable so if the final o.d. was out by more than .001" I tore everything off and started over. I also measured the capstand from several different angles to be sure that it was round. If it wasn't then I'd start over. Yeah, it was a long tedious process. That's why I don't do it any more! Joe

At 11:19 PM 2/4/06 +0000, you wrote: Tony's right. Two things can happen. First, reading the tape will cause the media to shed but even worse is that if a tape is used with a gooy capstan the goo will work it's way into the tape and gets wound up bewteen the layers of tape on one of the hubs. Then it dries there and the next time that you unwind the tape to that point the dried goo pulls the media off the tape. I've also HEARD that some of the tapes also stick together due to fungus, moisture or other things with the same results. You can deal with the first problem by absolutely minimizing the tape useage. Read each file then save it on another tape or drive. DON'T play around with the drive and tape! As for the second problem I guess you could try unwinding/rewinding each tape by hand to look for any sticking tape but I haven't tried it. It seems like it would be pointless since you probably coudn't do anything about it even if you found a stuck layer. Also the HP-85 tapes and 98xx tapes are EXACTLY the same and have the same PN. So are the ones used in the HP protocall analyzers, spectrum analyzers, 2648 terminals and ALL HP products of that era except for the big DC-600 type tapes used in the HP 9144, etc. They did use a different tape in some earlier products but they were VERY different and immediately recognizable. I have a couple of those drives but I've never seen a tape for them. It was driven like an audio cassette tape via the hubs. Joe

On 2/5/2006 at 6:59 PM ard at p850ug1.demon.co.uk wrote: No--the DC-300 is a big tape, thinner, but almost the size of a VHS cassette. DC-300, DC-600, DC-6150, DC-6250 and several other formats share the same mechanical layout and size. I've still got a bunch of the little DC-1000's squirreled away. The drive (Iwin) has 3.5" FH form factor. Are there any other 3.5" DC-xxx drives? Anyone remember a really silly format brought out about 1993? Used a 2.5mm tape in a cart about the size of an audio microcassette. The mechanism was a Sony helical-scan setup. It could run on 4 AA cells and interfaced through the parallel port. I was sent one as an evaluation unit and never could get it to work reliably. Tapes were expensive--about $15--and available only via Fedex from the manufacturer. I normally don't send many eval units back, but when I got wind that the manufacturer was telling customers that that we "were working on a driver" for it, I sent the unit back with an angry letter. One of my customers bought 50 of the units anyway and, for all I know, they're still sitting in a warehouse somewhere, unopened and unused. Cheers, Chuck

On 2/6/2006 at 12:07 AM ard at p850ug1.demon.co.uk wrote: Maybe a DC-100? Cheers, Chuck

I picked up a 2nd 2648A in Boise, ID and the capstans look intact on this one (looking into the case from the tape slot). This gives me one crappy unit for spares and one good condition unit for play :-). Now what's a good way to clean the stateful switches on the top of the keyboard? One of the keyboards has switches that don't release without a little manual assistance. I figure gunk has gotten into the switch mechanism over time. I'm *not* going to put this guy through the dishwasher, I'm too scared of what might happen ;-). Also, some people were saying that they had a keyboard "without the tape controls on top", but everything I can see in the 2648A manuals shows that all the keyboards have the tape controls, but your keyboard might not have the key overlay. Can someone show me a picture of the keyboard *without* the tape controls for comparison and get a part number off it? -- "The Direct3D Graphics Pipeline"-- code samples, sample chapter, FAQ: <http://www.xmission.com/~legalize/book/> Pilgrimage: Utah's annual demoparty <http://pilgrimage.scene.org>

In article <m1F5WhB-000IyFC at p850ug1>, ard at p850ug1.demon.co.uk (Tony Duell) writes: Anyone tried readtapes.com with one? -- "The Direct3D Graphics Pipeline"-- code samples, sample chapter, FAQ: <http://www.xmission.com/~legalize/book/> Pilgrimage: Utah's annual demoparty <http://pilgrimage.scene.org>

At 07:11 AM 2/5/06 +0000, you wrote: I don't know of any way to prevent it. The case of NIB HP tapes that I had had been stored inside in an airconditioned building on an Air Force base so storage conditions don't seem to be a factor. Other brands of compatible tapes such as the DEC CompacTape (or whatever they call it) and the PC 40 Mb tapes seem to have the same problems but not as often. But I think they're all going to deteriorate soon. I THINK the DEC and PC may be a bit newer. The HP Journal that talked about these tape drives said that the tapes and drives were developed by 3M and HP. So I believe HP was the first to use them so the HP tapes are probably the oldest out there. I don't know what good taking the belt off would do. I urge everyone to gather their tapes up and try to have someone read them and store the contents to disk or some other media. Joe

At 09:40 AM 2/6/06 -0700, Richard wrote: I don't know but it wouldn't surprise me if there was. But there are lots of other systems that use the same drives and tapes such as the HP 9845, 9835, 9825 calculator/computers along with LOTs of their test equipment. Joe I don't see

In article <43E7D828.2080104 at mcdermith.net>, Bill McDermith <bill_mcdermith at mcdermith.net> writes: Right, the graphics "terminal" -- its really more like a PC, but externally it looks like a terminal. Inside is a card cage, processor, memory, tape controller, etc. This would be the first I've heard of that; sounds like an internal hack and not a product as I can't find any mention of software products for the 2648A anywhere in web sites or HP docs. I don't suppose you have a tape? :-). -- "The Direct3D Graphics Pipeline"-- code samples, sample chapter, FAQ: <http://www.xmission.com/~legalize/book/> Pilgrimage: Utah's annual demoparty <http://pilgrimage.scene.org>

In article <1e1fc3e90602071348h508dbd61ide07338198a2c047 at mail.gmail.com>, Glen Slick <glen.slick at gmail.com> writes: Unreadable as in the media is physically damaged or unreadable as in the physical shape is OK but putting it through the drive doesn't yield anything useful? It wouldn't be the first time I've seen someone use a different read head with older tapes that were "unreadable" and squeeze out the bits with modern signal processing equipment and an analog signal from a compatible head. -- "The Direct3D Graphics Pipeline"-- code samples, sample chapter, FAQ: <http://www.xmission.com/~legalize/book/> Pilgrimage: Utah's annual demoparty <http://pilgrimage.scene.org>

On 2/7/06, Richard <legalize at xmission.com> wrote: Unreadable as in the common problem with this type of media where the oxide has been shedded from the tape in a few spots. I'm not sure how many tapes there are where I know this has happened. I might have just not bothered looking at the other tapes and assumed they would all have the same problem. Maybe I'll look into the 'baking" suggestions and see if that helps with some of the tapes that have not yet been damaged.

On Tue, 7 Feb 2006, Glen Slick wrote: Something about Autoplot triggered a distant memory, and I found a couple of 5-1/4" diskettes which may be for the 2647F. The first is labeled AUTOPLOT/47, with a part number of 02647-13401. If I'm reading the hex dump of what appears to be the directory sector correctly, it has the following files: WELCOME SLIDEX PIE AGLX AUTO AUTO2 AUTOX AUTOX2 CTUL001 BASIC LINEAR BAR SLIDE BACKUP MESSAGE1 There are two other diskettes, with DEMO/47 and something else I'll have to check on when I get home. What filesystem format did the 2647F use? Mike Loewen mloewen at cpumagic.scol.pa.us Old Technology http://ripsaw.cac.psu.edu/~mloewen/Oldtech/

On 2/10/06, Mike Loewen <mloewen at cpumagic.scol.pa.us> wrote: Can you create a disk image of the 02647-13401 disk (and other 2647 disks you may have)? The "getting started with your 2647F" manual (02647-90036) I have says that disk 02647-13401 is the BASIC / AUTOPLOT / 47 disk that I am missing. According to the manual the disks should be formatted with 256 byte sectors, double sided, 16 sectors per track, 1056 sectors total, which must mean 33 tracks, although the 13272 Flexible Disc System manual (13255-91223) says there are 35 tracks.

On 6 Feb 2006 at 16:13, Bill McDermith wrote: HP sold a 2647A terminal (I have one) with dual DC-100 drives that came with a BASIC interpreter on mini-cartridge. The tape label says: Hewlett-Packard Multiplot/BASIC Interpreter 02647-13301 Rev. F 2114-42 -- Dave

On Wed, 15 Feb 2006, Richard wrote: Each 264x terminal is programmable. You can write your own machine code and load it either from remote or from the tape drive into memory and execute it. There are several games for these terminals that run on the builtin processor, for both the i8008 (e.g. HP2644) and the i8080 (e.g. HP2645/48). The system calls are well documented in the technical manuals, as well as all ROM entry points, variables etc. I have about four or five *thick* binders for the HP2648 with detailed technical descriptions, microcode listings and schematics for all options that were available. Christian

On Sat, 4 Feb 2006, Tony Duell wrote: So you try to shred a tape first and after that you begin to think about it? Everyone who *knows* that the belt is sticking opens the cartridge and tries to unstick the belt without damaging the tape. This works very fine by applying heat (similar to baking sticky tapes, but here the tape is not sticky, it's only the belt). And the tapes are fine afterwards. It's how I revived all the original HP cartidges with software for the HP1000 (dated from 1980 to 1985) that I have. I've made backups, of course, but they are still fine. There are other tape cartridges that are really bad, notably DC-300 QIC tapes from around 1977-1982. They have sticky belts *and* sticky tape *and* a belt that will simply tear when the tape is moved. Christian

Lyle Bickley wrote: heh. good question. I've found that 130F is fine for most tape. Over 145-150F seems to cause problems with the plastic housing & flanges (but the tape seems fine). At one point in time Ampex recommened 130F for baking. My experience is that the RH in the area around the tape while at temperature has a lot to do with getting the moisture out (which makes sense... pv=nrt) I've baked tapes for as little as 7 hours and as long as 5 days. The time does not seem to be as important as the RH around the tape. -brad

On Monday 06 February 2006 01:23, Christian Corti wrote: Thanks! Lyle -- Lyle Bickley Bickley Consulting West Inc. Mountain View, CA http://bickleywest.com "Black holes are where God is dividing by zero"