I have one. it's a big paperweight without the microcode tape.. the 725 was a cab with an integreated internal/etc rc25 combo. memory is very limited . your tape drive wheel may be mush with age, so try to check it before sacrificing your ony boot tape ;0 h ----- Original Message ----- From: "Stephane Tsacas" <stephane.tsacas(a)gmail.com> To: "General Discussion: On-Topic Posts Only" <cctech(a)classiccmp.org> Sent: Sunday, November 28, 2004 1:26 PM Subject: Re: VAX 11/725 1983. functioning properly?

"Heinz Wolter" wrote: I would not bother with the boot tape. I'll bet $ the roller is mush. But if you really want to use it send me your address and I'll send you a few inches of norprene tubing which you can use to replace the roller. instead I'd connect the tu58 to a db-9 and run tu58sim on a pc running linux. I have a boot tape image which will boot quasijarus on a 730. I think that should work on a 725 also. That's how I boot my 730 all the time :-) works like a champ. And netbsd won't boot on a 725/730. Quasijarus will. I got close to fixing this at one point but decided Michael was right - bsd43 is the right tool for that job. netbsd is too big and bloated. You can boot bsd43 in 2mb of ram on a 730. -brad

Personally I'd rather rebuild the roller (I've done HP [1] ones, I can't believe the DEC ones are any worse) than adulterate a perfectly good DEC PDP/VAX with a PC :-) [1] Including the 9100 and 9810, for which I had to make special tools... As am I!. In the case of the 11/730, I think you want to remove the TU58 chassis as well, you don't want to cook the chips on its controller board if the PSU is malfunctioning... I really must dig out my 11/730 and get it going. I've got the R80 drive and the TSU05 magtape system (this was a standard cofiguration in half-height rack). Of course I've also got an RL02 on one of my 11s that I could hook up. What are my choices for an OS, given that I have no official license, live in the UK, and am not a member of DECUS (the UK chapter charges an extortionate membership fee). -tony

On Sat, 4 Dec 2004 00:56:42 +0000 (GMT), Tony Duell <ard(a)p850ug1.demon.co.uk> wrote: The DEC ones should be identical... I've done several DEC and one HP (line analyzer) But one big advantage to a PC TU-58 emulator is zero seek time; it eliminates delays caused by non-optimized boot tapes. The other is that you never have to worry about having a clean tape handy if you want to make changes. Finally... no read errors. That having been said, I have several TU-58 drives and do still use real tapes, but I keep meaning to fiddle with an emulator someday, but one that is dedicated and has an LCD text display to select which tape/and or internal memory slot. Also, ideally, a TU-58 emulator should talk to the outside world, even if over a serial line... I could see building one that serves virtual tape images via HTTP/PPP... Ow. Indeed... a quick thing to do - disconnect one plug and it's safe. -ethan

On Fri, 3 Dec 2004 20:05:14 -0500, Heinz Wolter <h.wolter(a)sympatico.ca> wrote: Yep... the HD is also called an RB80 (to distinguish it from the RM80 and RA80)... is still marked "R80" on the front, though. Those aren't as robust as an RL02, but plenty more robust than many RA81s... shame it's only a DEC-proprietary pseduo-SMD interface... no other drives work with it. For the weight and power consumption, an "RB-81" wouldn't be the worst thing in the world to ever have existed. OTOH, if you could _afford_ an RA-81 back in the day, you probably weren't likely to hook it to a CPU that cost _less_ than the drive (price point: RA81 in mid-1984 was ~$24K US, I _think_ an 11/730 was $30K at release, but I could have mis-remembered; the 11/725 was always less than the 730, but license costs were probably similar ($10K?)) AFAIK there's nothing preventing one from installing the IDC card into a 11/725 and hooking up a real RL02 up... would still be DQA1: to VMS AFAIK. Could even boot SA backup and/or diags from it. Given that I saw lots of boards in the KA730 set die and never saw on e dead IDC, it might not be too hard to find a spare somewhere - and the RL02 cable is the standard 40-pin one like you see on the RL11. Right. Also... can't change removable platters on RC25 if booting external drive (or Unibus SCSI and _internal_ 3.5" drive... power wouldn't be an issue there!) -ethan