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Test Equipment Anonymous (TEA) group therapy thread
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Robert763:

--- Quote from: m k on July 03, 2022, 11:37:30 am ---
--- Quote from: mnementh on July 03, 2022, 01:34:23 am ---WELCOME TO 5000!           

--- Quote from: factory on July 02, 2022, 07:48:19 pm ---From the Agilent 54654N diagrams, that were linked to recently.
The monitor cable has three connections for +15V and ground, six total.
Three connections for the intensity pot.
Last four connections are half bright, full bright, HS (Hsync?) and VS (Vsync?).
Interesting the HS goes through a 74393 to provide the probe compensation signal.
HS & VS come from the big Jackal custom IC and the half bright, full bright from a PAL IC.

Other relevant pages have been cropped, rotated & added below.

This forum post suggest the Hsync is 19.72kHz and the Vsync is 60Hz.
https://www-elektronik-si.translate.goog/phpBB2/viewtopic.php?t=30373&postdays=0&postorder=asc&start=30&sid=c8ec2c01726d6cc1ee123fe5ebbe8c3d&_x_tr_sl=auto&_x_tr_tl=en&_x_tr_hl=en-US&_x_tr_pto=wapp

Guess I need to locate those on my 54615B, to try & narrow down where my intermittent horizontal roll problem is, but it's not the same board.

David

--- End quote ---

Okay, I've traced out the 54621D and the VCC, GND are in the same locations, plus Pin 10 dssig_grd is also tied directly to GND. However the BRIGHTNESS pot is not brought out to this header on the 54621D.

   
                        VSync                                                    HSync 
   
My guess is that 13/14 are still the sync signals, and they have repurposed 7, 8, 9, 11, 12 for their greyscale scheme. 54645A agrees; trace 1 is the 54621D, trace 2 is the 54600A.


   

However, pin 8 is a different story; all I'm getting from the 54600A is noise.   :wtf:

Then the light dawns; the pot isn't connected to the monitor PCB, duh. Then it occurs to me the voltages usually present on a brightness pot, so I connect the cable back in the 54600A and probe the pot. Yup... (-58V) sent out pin 9 to the pot. Without knowing how the 54621D does its greyscale, I'm not too sanguine about connecting that (-58V) back to its mainboard.

I think this is probably a good point to call it a night. ;)

mnem
 :-BROKE

--- End quote ---

So you were not short of machines, all clear then.
Better also that incoming voltage is not 125V.

Maybe one final thing, 31 of Toshiba E9054B31-CDHT is green.

--- End quote ---

I just visited my storage unit to get the TEK 7000 kit that someone decided to buy. While there I grabbed a HP 8922M monitor that has similar signals to this one. I'll whip the screen off and take some pictures later.
nixiefreqq:
from my 54622d
nixiefreqq:
more from my 54622d
Cerebus:

--- Quote from: vk6zgo on July 03, 2022, 06:37:01 am ---Yonks ago, I remember driving a 100E Ford Popular back from London to Southampton on the M3.
Back in those days, the Poms were well into tailgating, with the worst offenders being "chaps driving Jaguars".
Downright terrifying, with the poor old "Pop" screaming its guts out, and a Jag bonnet emblem seemingly in the back seat.

Tailgating was not rare in Oz at the time, but I was surprised how 1970s Brits made an artform of it!
"Culture shock", I guess!

--- End quote ---

Since those days the tailgating in Britain has gotten worse, and it doesn't matter what make of car is behind doing the tailgating or in front being tailgated.  I'm as likely to be tailgated by Nissan Micra as I am by an Audi SUV. I'd say 1 in 5 cars that gets behind me holds back to a safe distance, so 4 in 5 are too close ranging from  half what it should be to "What have you got in your boot mate? I want a look.". It seems like the average driver no longer has any grasp of basic common sense physics ranging from optics (what they can see) through to dynamics (how soon they can stop), or physiology (what it will do to their bodies when they come to a sudden stop). There are days when I feel that I need a rear gunner with at least a 20mm cannon.
Cerebus:

--- Quote from: bd139 on July 03, 2022, 11:06:40 am ---Depends how many posts people deleted  :-DD

Revisionist bastards!  :-DD

--- End quote ---

Bleeding bloody splitters! :-DD
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