Thanks for the suggestions. I’m in Sunnyvale, CA. I actually got the rx02 from another hobbyist that used it with the 44 in 2008 so I suspect it is configured correctly. The other drive doesn’t have a belt so I’m unable to test with it. I’ve verified the cable direction. It’s a sweet 44 - super clean, runs great and is like a tank.
One of the problems is I don’t know normal behavior of the drive. The motor is aways spinning for unit 0. When I try booting I don’t hear the heads load or seek. I’m new to the 44 monitor commands & boot process etc so I’m learning as I go. I’m also making one of these to help isolate if it’s a drive/cable/controller problem: http://www.torok.info/computing/pdp11/rx02/index.htm Kirk > On Aug 2, 2016, at 3:24 PM, Paul Anderson <used...@gmail.com> wrote: > > Hi KIrk, > > The H771 is a rock solid power supply. I never saw one go bad while in > field service, but they are getting old. Checking the output voltage and > ripple is not a bad idea. > > forgive me for asking, but where are you located? The RX02 had 4 different > power hanesses for i20, 220, 50 hz and 60 hz. Also different belts amd > pulleys. if any of this is wrong you cn see weird problems. A lot of RX02s > and replacement drives were soul through brokers who never asked or were > never told where the unit was going. if you aren'y useing 120/60 that > would be my first thought. > > Is the problem the same when booting off either drive? Also check the > switches and the resistors on the head cables. > > Good luck, Paul > Jerry Weiss wrote: > >If you haven’t already, check the cable seating, orientation and for bent >pins. > On the RX211 board J1 - TT is the location of the AC LO - Active Low signal. > > On Tue, Aug 2, 2016 at 4:06 PM, Kirk Davis <kirkbda...@me.com> wrote: > >> I’m a noob using RX02’s but thought I’d run this past people that may have >> debugged them in the past and see if they agree with what I’m finding: >> >> I’m trying to get a RX02 + RX211 + 11/44 going. The RX02 appears to power >> up OK (fan and motor spinning). I verified I have the DY boot rom in the >> 44. Attempt booting from the console: >> >>>>> b dy >> >> S >> 17777707 173436 >> >> Which halts in the DY boot rom. I look at the base RX211 register: >> >>>>> e 17777170 >> 17777170 104040 >> >> From the manual this like the controller is present but the high order bit >> is set indicating an error >> >> Looking at the status register; >> >>>>> e 17777172 >> 17777172 000010 >> >> Bit 3 == RX AC LO - This bit is set by the interface to indicate a power >> failure in the RX02 sub- system. >> >> So start looking at the RX02 power supply? >> >> >>