[KL] control panel tact switch access on K2500X???

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Hello All! I just started getting around to replacing some tact switches for my K2500X - after figuring out how to open it up and removing all the other boards I needed out - to my CHAGRIN it looks like the one board I need to access is inaccessible... it's cemented in along what looks like a card interface which seems to be the input for the ribbon controller (!!) - i havent' been able to find much info on getting this far - not even in the service manual so this was a total surprise! I have no idea how to get the board out now...

any advice?

the only solution i can THINK of at the moment - is to cut out the front panel surrounding each tact switch to access them that way - then solder the new ones in from the back... but surely there has to be a better way? I see nothing in the service manual either.

thanks in advance. i hope someone can help!

jonathan

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fixed that problem and created a new and bigger one!

okay well - i got it mostly licked. the switch armatures were a real bitch to get back in with the cover on - found a neat trick that worked after super gluing them to the board failed me... used gaffer tape to hold the assembly to the TOP of the front panel and attached the board after... seemed to work a lot better...

I booted it up - worked great after extensive initialization then futzed about trying to get the case back on properly- tried booting it up again and now my display is all screwy! any ideas? it's gone all white - like it's on max brightness - i can JUST make out text etc in the display and it's responsive - so i guess it's not a CPU issue. I'm wondering if something could have somehow happened with the contrast? anyone ever experience this before???

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Since you can see the text, hold down the "Enter" button and turn the data entry wheel until you can see the text. This is the "fine contrast adjustment" but it's infinite -- once you can see the text, set the contrast parameter on the master page and power cycle your K2500X.

If that doesn't fix the problem, locate the variable resistor R72 on the keyboard (R246 on the rack unit), which is the coarse contrast adjustment. With the unit powered on, adjust the coarse contrast to your liking and finish it off with the fine adjustment.

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ok cool thanks I'll try it and get back to you- i thought it must be a contrast issue somehow - i was wondering if maybe it wasn't because I was routing the data feed cable to the display board BEHIND the the HV transformer board and was somehow inducing a current there ... well who knows... anyway I'll check for pinched cables first and then try what you suggested... thanks

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checked through all the connectors/grounds etc... no go. and i have a NEW symptom - not even getting any audio now (before this i could at least play presets/programs and hear it out of the outputs/headphone jack

i'm starting to regret even opening this thing... :P

the random flipping through presets that inspired me to change the tact switches is starting to look pretty good by comparison!

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Okay - i guess i got it licked now (finally) - maybe this can be a lesson for others in the same situation - on a hunch i stripped out all the boards again (I know!) and discovered that the connector between the slider board and the button board was coming loose... not much at all - i had to (awkwardly) push the connector another millimeter closed... then put everything back in and everything worked as it should!

[[e-mail] [KurzList]]

Okay -- glad you got your problem located! If you find it's an ongoing issue, you might want to consider putting a drop of glue over that connector.

Obviously it was a little too late in your case, but a couple things I did the first time I had to "go deep" into a Kurzweil, I took a lot of pictures of everything from every angle, then made little labels for each connector with the number on them. The "Kurzweil-K2600" list has the service manuals in their files section along with a metric ass-ton of other K2500-related goodies (I wish were here).

Anyway, congratulations on getting your K back in operation!

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okay thanks! - and thanks especiallly for the info on the service manuals etc... i didn't know that group existed!

Yeah i normally take pictures when there is a situation where i can get connectors backwards or interchanged. I did that when working on my polysixes, my mono/poly and arp omni and odysseys

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now i just have to figure out how to get the top of the shell back on properly! :P
(pretty sure i damaged something - not fitting the way it was earlier!)

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Yes, the K2500 service manual has a special section on reassembling the keyboard. Essentially you have to assemble it by tilting the top cover back onto the body, lowering the front starting at the left end so the floppy bezel is in place. Then drop the right end in, making sure no cables are being pinched and the spring fingers are not bend. Once everything is in place, slide the top cover forward so the spring fingers interlock with the holes in the top cover.

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yes thanks - i read it - though i did it several times already and I don't think it's designed with fabrication to be done more than 3-4 times... it fit together nice and snug the first 4 or 5 times then i started having problems... anyway... i'll work it out somehow thanks

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hmmm... i discovered that it's not going to be so easy for me... apparently NOW none of the front panel buttons are responding - luckily it restarted with just a tad more contrast and I was able to read characters on the screen. But gosh - I must have plugged something in backwards (didn't know that was possible), reattached the ground in the wrong place or else damaged something while trying to get the top back on last time ... but they were ALL working before (I guess that's an argument against the backward connector theory though huh?) this screen thing happened...

also i noticed that i forgot to plug in the SCSI/HDD data cable back into the backlight board (I think?) - and when i did i got a nasty loud buzz out of the headphones...

curiouser and curiouser ...