Hi Jerry, swap the M8639-YA and the M8029 for starters! The M8639-YA is the RQDX1 and is the famous board that does NOT pass NPR/grant. It is even stated in the Field Guide that the RQDX1 must be the last board in the chain... gd luck, - Henk, PA8PDP. -----Original Message----- From: cctalk-bounces at classiccmp.org [mailto:cctalk-bounces at classiccmp.org]On Behalf Of g-wright Sent: dinsdag 5 juli 2005 19:29 To: cctalk at classiccmp.org Subject: Need help with a 11-23+ and a RX-02 , Repost Hi, I'm trying to get one of my 11-23's going and finally got around to setting up a TU58 emulator. got it to boot RT-11 and now trying to get a RX-02 working. I have 3 controllers and 3 sets of RX-02's. All do the same thing. The just seems to not be able to find track 1 or Home or ??? The heads just keep going from home to maybe the first tack and back. The heads do load and the system tries quit a few times then pauses and tries again. It then errors on drive failure or read error directory not found, size function failed depends what I ask it to do. I have tried all of the boards and drives. all or them seem to do the same thing. I do not know how good the drives are but can't believe there all bad. I have recheck the switches in the RX-02 and the Jumpers on the cards. Cleaned the drives. tried different disks. Is there some kind of compatibility issue that i do not know about. Or do I have 6 dead drives. The system is a Micro PDP 11, 8 slot Rack mount, with 1 M8189 11-23+ 1 M8067 KB 256k Memory 1 M8639 YA MFM rx50 controller 1 M8029 RX-02 controller - in this order. Everything else seems to work. I added the floppy card but the rest is original. Thanks, Jerry Jerry Wright JLC inc