Looking for RL02 cable and terminator

I know for a fact that there is no issue with a lack of brushes. I have an original factory RL02, and an RL02 that was converted at the factory from an RL01, and neither of these units contain brushes. It is my opinion from what I've looked at that the brushes were removed from later revisions of the drive (and even possibly by field service) because they would damage the disk surface. If you want to keep your disk cartriges clean, change your absolute filter and clean the head, and don't switch disk carts too often. My main system RL02 has been running flawlessly with the same disk pack 24/7 for 2 years now, and I haven't even changed the absolute filter yet. To clarify the issue of the FAULT light being on, the drive WILL fault if not connected to a controller. I'm 100% sure of that. Does the RL8A controller specify a special RL8A cable in the package descriptions listed in the RL01/02 manual? From what I remember, they only vary in length, not style. There's only berg-to-RL02 and RL02 to RL02 cables of different lengths. -----Original Message----- From: cctalk-bounces at classiccmp.org [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Tony Duell Sent: Monday, October 17, 2005 6:30 PM To: cctalk at classiccmp.org Subject: Re: Re: Looking for RL02 cable and terminator That's the opposite to what I've seen and heard. The RL01's in my MINC are the earliest version, the drive logic board does not have the RL01/RL02 jumper, it's strictly RL01 only. That drive has the brushes. I've mever seen an RL02 with brushes. On a late-design RL01, that's a fairly easy change to make (a few links on the boards, new heards, and maybe a new spindle if the older, less accurate, one is fitted). I would not fit the brushes. I don't know if there was a logic change (maybe a different state machine ROM or something), but I do know you can get a working RL02 without the brush mechanism. I would assume your drive will work without it, at least until you prove otherwise ;-) The pinouts are the same at each end... But remmber if you do this you'll need to do something about termination. Either kluge a resistor network into another connector at the drive end of the cable, or use one of the connectors on the back of the drive with a real DEC terminator (if you can get one). When you open up the drive you'll see a short 40 way ribbon cable with 3 Berg connectors on it. One plugs into the drive logic PCB, on the bottom of the cover. The other 2 plug into the back of the rear panel cable connectors. You could make a longer cable with 2 conenctors near one end (drive logic PCB and one of the rear conenctors) and a single connector at the other end for the controller. Then just plug a terminator into the rear connector of the drive. One other minor caveat. The drive supplies 5V power on one of the corner pins (check the printest) of the connector to power the terminator. This is deliberately not connected between the drives (connecting PSUs in parallel is generally a bad idea). I don't think it's connected anywhere on the contoller board, but you might want to check the printset and remove the offiending pin from the controller-end Berg connector if necessary when making the cable. -tony