LCD readout - broken ? or bad joints

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Have a problem with the LCD display on my CDP, i'm wondering if its dead pixels or maybe dry-broken joints.

This thing has just been delivered to me and i suspect its transport damage, but any ideas what its gonna take to fix ?

Thanks -
 

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It could be either. Are you able to remove the LED display for testing?
At least they look as if they are a standard size. Changing both displays could well be an option if you want to change the colour or just to make doubly sure that they match perfectly.

What's the situation? Did it come to you for repair or have you purchased it? Would you get a decent discount if you repair it yourself?

Test the segments yourself just to eliminate an outside chance that the microprocessor is playing up. Chances are though, IMO, that it's worth a punt.
Very worst case scenario: live with the dodgy but readable display but add a switch to turn it off. Lots of players have this facility anyway!
 
I've had a look inside the machine and it looks easy to access the LCD, i'm just a bit reluctant to start the job...

Yeah the display can be turned off, i'd rather get i fixed though.. i'm gonna wait until i can get hold of a ground strap, a bit worried about risk of damage.

I just bought the player but not from a dealer, the price i payed i guess i could live with the fault, but i am gonna have a crack at this !

thanks.
 
Often the 7 segment LED displays are in sockets, try swapping them and see if the fault follows the display.
Unusual for LEDs to fail like that in a properly designed circuit.
Unlikely to be transport damage, if it is it will be a ribbon cable half pulled out or something. LEDs are tough.
The display MIGHT be LCD with a red backlight, LCD are a little delicate and very sensitive to static. The glass contacts are hard to clean, we used to use some special green plasticine like stuff to clean the zebra crossings. It was hard stuff to find too, I have no idea where to get it or what it is.
 
Ok the CDP is still working, but the display is not..

It looks like they are LCD's soldered in with 12 (i think) pins, we re-soldered a load of joints including what looked like 2 controller chips, no luck.

also did a search on the model no's for the LCD's and control chips, nothing...

Decided to leave this for another day when my brother has more time to help cause it really is a 2 man job, such a huge beast :)

btw, i thought i'd capture the Krell while she was naked -



http://www.affinity3d.com/gallery2/main.php?g2_itemId=273
 
They are LED, not LCD.
Light Emitting Diode.
Liquid Crystal Display.

Each module should have a part number on it.
Maybe send krell email.
LED displays are cheap and normally very reliable.

By the looks of the interior, I imagine all boards will be through hole, so I doubt it will be dry joints.

Try and find the part number and replace them.
 
Been a long time...

I finally got around to looking at this again, swapped the 2 LED modules over to test and is the LED at fault, contacted the krell distributer here, they are contacting krell for price and availability, still waiting for reply.

I do not expect that this will be quick, easy or cheap, if the story's i've heard about krell voltage conversions are true...

I did try googling the part number, but only suppliers that come up are those with the $300 minimum order rule :rolleyes:

Anyway, the part number is HY-214 94V0 if anyone has any ideas where i could get these led's please let me know.

thanks
 
From what I can find, it looks like it may be an older 4 digit 7 segment LED display from General Radio (now defunct). How many pins does the display have? Posting photos of the LED display board out of the case may help, as will posting the name of the controller chip the display is connected to.
 
Mooly said:
Looks slightly like a Philips display module. Does it have an IC built into the board which looks like a "blob" of black epoxy. The Philips ones were well known for failure but the ones I worked on were green.

I agree... Looks identical to the Philips modules.

I just repaired the display on a newly acquired CD202 tonight by flowing solder through all the vias.

Went from having 5 working segments out of 32 to 29 working out of 32 (the missing ones were on the first digit, which always shows "0" anyway)... Not perfect, but a far better result than when I first got it.
 
Mooly said:
Looks slightly like a Philips display module. Does it have an IC built into the board which looks like a "blob" of black epoxy. The Philips ones were well known for failure but the ones I worked on were green.

Yeah, on the back of the pcb, the pin spacing is a bit different to the one shown, but i guess that might not matter, here is an image of the pin positions -
 

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