PERQ monitor problem (was HP 9845 power supply diagnostics) - test-drb@ccmp.vtda.org

27 Oct 2012

Tony, 

Sorry, didn't get to the PERQ monitor this weekend.  Francis was looking at the 2645
(with me sorta offering moral support).  Hopefully get back to the 2645 next week. 
PERQ's in the queue. 

--Colin

ard at p850ug1.demon.co.uk wrote:

...

 My recollection is it was both rolling and skewed. I need to get it in  
Right... Sounds liek capacitor trouble at a first guess..

  the queue for our CRT doctor to look at. He's
got a never ending stream 
 of Cubs to deal with supporting our BBC classroom systems.  I have to  
Ah, the Microvitec Cub. I remeber those... They are one of the few 
'consumer' monitors of the period to use an EHT multiplier module (a 
tripler IIRC), most small colour monitors went over to the diode split 
line output transformer. The tripler design is probalby easier to fix -- 
the transofmer is less stressed ('only' 8kV o nthe end of the HV winding) 
and tends to last better. The tripler is a potted module, but it's 
possible to make an equivalnet or to find soembody who still has a 
'universal tripler' on the shelf....

  nudge the PERQs monitor in among them, as well as
an HP 2645 scan card 
 that's puzzling me. I may have mentioned (?) I took the expedient 
 measure of swapping the base from one monitor for the other to address 
 the cable sheathing issue we had. This leave us the backup monitor on  
You mentioend the cable problem. It's is. alas, common on PERQ 1 machines.

I guess you've not managed to track down the fault in the monitor, then. 
The PRERQ 1 monitor is not too unconventional from what I remember, and 
it not a bad one to learn on. You should dive in with a 'socpe....

  the injured list waiting for the  doc. 
I wonder if it would be worth gettign the repairer to appear on this 
list, that way we can cut out the middle man and reducew the chance of 
errors...

-tony