Nick, I know about this from talking with Al about this subject: the drive does NOT connect to the PC. Al wrote a program that (as he said) runs on the Alto, talks through the utility port on the Alto, and communicates with another program running on a modern PC (actually, ISTR, a Mac). If your Alto isn't running, it won't help you. Take a look at the documentation (available on Bitsavers) regarding the disk interface, if you have any doubts as to the challenge of what you suggest. -- Ian ________________________________________ From: cctalk-bounces at classiccmp.org [cctalk-bounces at classiccmp.org] On Behalf Of Nick Allen [nick.allen at comcast.net] Sent: Friday, October 22, 2010 12:11 PM To: cctech at classiccmp.org Subject: Re: Test Diablo Model 31 drive and disk pack on a PC (Operation Alto Restoration) Sure, I will upload the photos shortly. Did you have to build a custom cable/adapter from Diablo to the Parallel port on the PC? Did you use any a custom drive, utility, os on the PC side? Just looking to validate somehow that my Diablo Drive is fully functioning, and this direction seems to be the best bet until I get the Alto working.

If I rememebr the Model 30 (which is very similar) correctly, it does not need the cotnroller to go ready. It's a good idea to haev the terminator fitted, though, I seem ot remember that on some drive the write gate line can become asserted if it floats, leading to a corrupted disk. For the same reason, if you don't have the controller boards fitted or powerred, it's a good idea to unpluy the controller cable from the drive. I seem to rememebr that. at power on, the Model 30 notices it;'s not getting any index pulses from the (non-existant) disk, and after some seconds it wil lunlock the front door. At this point you can open the door and slide in the disk pack. Then close the door and press the appropriate button. The disk should then spin up, and when the drive thinks it's u to speed, it will load the heads. The Modle 30 is odd here i nthat this is not done my moving theh eads from the home position towards the spindle and thus having the heads come off a ramp. Istead there is a load solenoid on the side of the positioner which is energised. Now, since thrre is no sync/servo information read from the disk iself, the drive will go ready id the disk is totally blank, or if there's a problem with the heads or read/write electronics. Now what I would do is temporarily disconnect the load solenoid. Then power up, insert the pack and spin up. The heads then can't load, but thr disk should spin up, and the drive go ready. If it does, and the spindle seems to be spinning properly, then you can power down, reconnect the solenoid and try it for real (and hope you don't get a headcrash.) IIRC, these are 'midget flange' bulbs and are not easy to get. Last time I needed one, to put in an HP59306 relay actuator, actually, I repaired the old one (!). I could easily get wire-ended bulbs of the correct electrical rating, so I desoldered the connections on the cap of the defelctive midget flange blub, wrapped it in paper and crushed the glass with pliers, then cleaned out the base cap. Inserted the wire-ended bulb and soldered the wires ot the base contact and the cap. I don;t think you will get any seeking without having the controller working. Are you talking about the LOAD button on the Alto here? -tony

They are not easy to get if you do not look for them. They are actually quite common in the right places. -- Will

I must admit I don't normally buy components on E-bay. While virtually all of the sellers I've dealt with have been totally honest and great to deal with, I would rather buy things I can't repair (like components) defective. I remember whea I wanted bulbs for the HP 59306, I could find several companies who could supply them, but only in quntities of 50. Which was rather too many... Many years ago I rememebr getting some little metal collars that you screwed an LES cap bulb into, and the result would fit a midget flange socket. I think they came from 'Home Radio' of Mitcham (now that does date me :-)). They are presumably still made becuase I bought some LES panel lampholders a couple of years back and they turned out to be midget flange hoders supplied with these collars. But that's an expensive way to get them. -tony

Al, here is a link to photos of the Disk Packs, I have one more in the Diablo Drive I need to still remove and take photos of: http://picasaweb.google.com/NeXTprototype/Alto?authkey=Gv1sRgCKz9_Pm4wJ6Oag# Als