--- On Thu 08/04, Joe R. < rigdonj at cfl.rr.com > wrote: From: Joe R. [mailto: rigdonj at cfl.rr.com] To: cctalk at classiccmp.org Date: Thu, 04 Aug 2005 21:39:32 Subject: Re: Disk drive parts At 12:27 AM 8/5/05 +0100, you wrote:<br>>> The RK05 uses a DEC backplane<br>>> >block internally, with genuine Unibus cables (RK11D) or a DEC-style<br>>> >paddle connector and 40-pin ribbon cables (RKV11D, RK8E). <br>>> >_Electrically_ the Diablo 30 should be the same as a real RK05, but<br>>> >mechanically, the cables are entirely different.<br>>> <br>>> Yeah that was an unplesant surprise! <br>><br>>Althoguh if you get a real Diablo cable, it has the connector mounted on <br>>a little PCB, with a trasnistion connector and then a length of ribbon <br>>cable on that. If you take off one end, the wires are in almost the right <br>>ordser to solder to a DEC 'unibus' cable board to link to the RK11-C or <br>>whatever. I wonder why :-)<br>><br>>> <br>>> BTW I found out that the d30 uses an external power supply. Does anyone<br>>> have the specs or pinout for it or even an extra PSU?<br>><br>>I thought the manuals were on bitsavers. The PSU pinout should be in <br>>there.<br><br> Yes, the manuals are on Bit-savers but IIRC they don't recall them<br>giving any details about the PSU.<br><br> There were 2 PSUs from Diablo, one using a transsitorised <br>>regulator, the other using a ferroresonant trasnformer. DEC also made <br>>their own PSU (H734 or something) for these drives.<br><br> Can you check and make sure that that's the correct PN? If it is, I'll<br>go hunt for one. There are piles of DEC PSUs in Melbourne.<br><br><br><br>>> <br>>> ><br>>> >The drive chain also needs to be terminated. In the case of an RK05,<br>>> >it's an M930 Unibus terminator in the last drive. Not sure about a<br>>> >Diablo 30, unless you hang a real M930 off of one of those cable<br>><br>>The Diablo terminator is a PCB stuffed with resistors soldered to the <br>>connector. There's a +5V pin on the connector to power the terminator, of <br>>course. I have _one_ of them, I also have 2 drives and the <br>>interconnecting cables, so it's not up for grabs.<br><br> Do you have schematics for any of those?<br><br> Joe<br><br>><br>>-tony<br>><br>><br><br> I don't know if this will be helpful or not, but offer it anyway. I have a pdp-8i with two RK8 drive (really RK03s). The power supply is a Pertec unit (at least the manual I have for it says Pertec). It's labelled Model 9000. If desires I could try to get copies of specific pages for you. Tim Radde _______________________________________________ Join Excite! - http://www.excite.com The most personalized portal on the Web!