41CX: strange display problem


My new 41CX (halfnut, S/N 26...) seems to be a little bit confused: It displays none of the announciators (Flags, Shift, G/Rad, User, Prgm) other than Alpha. But: in Alpha-Mode, all is working fine, shift, flagstate, rad etc. pops into display. Unfortunatly all is gone again after leaving the alpha-mode...

Any ideas how to fix this annoying behaviour? Discharge to a "memory lost" doesn't help.


it IS confused, isn't it? i took my half nut out and once in alpha i couldn't get into program without it shifting out of alpha or play with flags, or xeq anything. however user could toggle. i don't know about this but mabye you could try a soft reset. it couldn't hurt but discharge to a memory lost should do whatever this will. press the back arrow and enter keys and hold them then press on and let up on all three. good luck; someone here will probably know what to do.


A hunch:

Is it possible that the COMMON connection for the other annunciators (PRGM, USER, G RAD, flags) is "lifted" (not connected) and, somehow, when ALPHA is lit, this connection is stablished by ALPHA potencial?

I have seen this kind of not-normal opperation in signaling panels using LED´s and lamps switched by transistors, never in LCD´s. Sometimes, when both COMMON connectors are lifted AND stay connected each other, this may happen if switched voltage is not the same. 41´s LCD, as all others, operate with three voltage levels.

I would also guess bad internal display connections. Did any battery leak?


"I would also guess bad internal display connections."

Sounds possible, i will check that if the seller give me his OK. I hoped it was a simple software- or user-problem but it seems to be more serious.

"Did any battery leak?"

Unfortunately ;) not, its in nearly mint condition, and i will be really sorry if i have to return it. My working-horse-CV looks (and feels, thanks to one loose screw-post(?) i have to repair really soon) quite ugly against this lovely CX...


Excuse-me, all.

"41´s LCD, as all others, operate with three voltage levels"

should be:

"41´s LCD, as many others, operate with three voltage levels"; some new LCD´s use four voltage levels.

"Sometimes, when both COMMON connectors are lifted... "

should be:

"Sometimes, when TWO OR MORE COMMON connectors are lifted "


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