Tektronix 4014-1 troubleshooting advice

[Paul Koning]

> On Mar 27, 2015, at 3:40 AM, Pontus Pihlgren <pontus at Update.UU.SE> wrote:
> 
> Hi
> 
> We have a 4014 at the computer club and that patterns looks very 
> familiar. It usually clears after a minute or so.
> 
> We have assumed it was normal and have not investigated.
> 
> Congratulations on a nice find! I'm quite jealous.
> 
> /P
> 
> 
> On Thu, Mar 26, 2015 at 10:03:03PM -0700, Josh Dersch wrote:
>> Hi all --
>> 
>> Picked up a Tektronix 4014-1 terminal.  It's in pretty good shape,
>> nice and clean and it's in nearly-working condition except that the
>> storage behavior isn't quite right.
>> 
>> On power-up, write-through doesn't.  (That is, characters don't get
>> stored to the tube.)  Clearing the display via the RESET/PAGE key
>> clears a roughly elliptical region in the center of the display but
>> leaves the outer edges a mess.  The cleared region stores characters
>> properly.  You can see the overall effect here:
>> 
>> http://yahozna.dyndns.org/scratch/tek4014/clear.jpg
>> 
>> After a 2-3 minutes of warming up the area cleared by RESET/PAGE
>> increases. 

No, that isn’t normal for a new 4014, but I could easily imagine things going out of tolerance in 40 years.  A schematic or manual might give a clue, if one can be found.

	paul