[GreenKeys] Model 33 bell problem

[Jones, Douglas W]

I've diagnosed the problem I'm having with my model 33 where the bell rings with every character received.  The log entry is here:
-- http://www.cs.uiowa.edu/~jones/pdp8/UI-8/log.shtml#2016-12-30

The problem is that the "automatic codebar" was inserted in the wrong slot in the codebar assembly.  My guess is that I'll have to do significant disassembly to get enough access to remove the automatic codebar and slip it into the slot one place closer to the front of the typing unit.

The exploded diagram for the whole assembly is on page 13 of the Dec. 1965 edition of the parts list for the typing unit.  On this parts list, you can see that slot 1 in the assembly should be unused while the automatic codebar goes in slot 2.  As misassembled, our machine has the automatic codebar in slot 1 and slot 2 is unused.

So, how far do I have to disassemble things to get extract the automatic codebar and re-insert it in the correct slot.  Can I do it from the right end of the TU without removing the platten and carriage, or do I have to remove the platten and carriage.  In the worst case I can imagine that this fix requires also removing the entire codebar assembly from the base, making for some really tricky reassembly since the codebar assembly includes the combs  that align the function levers and blocking levers.

Advice, please!

		Doug Jones
		jones at cs.uiowa.edu