Problems with VAX 11/750 console

Hi all, I'm trying again to get my 11/750 running. It turns on, power lights are green, machine comes up halted with the dim error light as it should. THe problem I am having is, I get no console...I get an echo back of the characters I type, but nothing else. Doing a BREAK command or a Ctrl-P does nothing. The closest thing I can find to this problem is in the 11/50 FAQ, found here: http://www.vaxarchive.org/hw/750faq.html Here is what the FAQ states: "Help! My machine isn't listening to the console! Symptoms: machine starts up normally and prints the successful microverify double percent and the console prompt, but ignores console input. This may be because the RS232 line receiver on the console port has given up the ghost. I've had to replace the one on mine twice. Note that it isn't a good idea to leave the console terminal switched on if the machine is switched off -- the line receiver chip doesn't like this and tends to fail eventually. To replace the line receiver: a) Locate and remove the L0004 UBI module. b) Hold the UBI component-side up with the edge connectors down the RHS. c) Locate E53, a 1489, at the right-hand side of the board, near the top of the second edge connector. This is the only 1489 on the board. d) Replace E53. I strongly recommend using a socket for the replacement. " Now, this does not sound similar to my problem. I have indeed verified that all the jumpers on the backplane are in the right place, and so are the connectors. The jumper is set to 300 baud, and that is indeed the only setting I get a clean echo back without garbage on. Any suggestions? I'm out of ideas at this point. Julian