So I finally got around to adding the illuminated buttons, and now the display no longer works properly. The symptoms are:
when in AC mode, the display is very dim. in car mode, the display is very distorted: i can somewhat make out what is on screen, but it's very difficult.

on the bright side, the buttons do light up. if anyone experienced something similar during their installs, please let me know. i hope i didnt fry anything expensive.

regards
-ted

You probably plugged the display connector back in "off by one pin".

Please click here for details.

once again, you da man tony! im on my way to frys now to find a fuse. good think the designers had the foresight to put them in!

-ted

Actually, thank Mike Munsell for that one.

And a few other people, including Hugo and David if I recall correctly, who spent some time helping early-adopters of the buttonhack troubleshoot this problem.

I have to say, I do find it rather funny that folks would go to all this trouble to carefully solder the molecule-sized traces on the resitor pack, but then go "oops" and plug it back in wrong.

I do find it rather funny that folks would go to all this trouble to carefully solder the molecule-sized traces on the resitor pack, but then go "oops" and plug it back in wrong

That's because they're in the "joy, joy, happy happy, finally got the little bugger in place" mode.

/Michael

I hear you on that one. It took about 4 hours just to do the button LEDs.. I was all jazzed to get it going! The biggest pain was clearing the through holes for the LED leads (they were filled with solder). Thank god I had good assembly tools at my disposal (vice grips, fine solder tips, etc.) After looking back, I see how it's easy to be off by 1 pin given the configuration.

Now I need to fix the freakin transistor on the knob PCB. I think I blew that puppy out too.

Regards
-Ted

My biggest pain was definately the resistor pack - got it slightly misaligned so it had a strong tendency to bridge... I lost count of the solder, measure, touch, desolder cycles But finally got it right. The LEDs were dead easy - a spring loaded vacuum lead sucker seems to be the proper tool (unless you have a proper desoldering station)

The knob stuff was relatively simple, though I got a really really tiny solder whisker going from the +5V pad to the emitter trace keeping the knob LEDs constant on max. Easy fix once found...

What's your knob LED symptoms, always on (max) or always off?

/Michael

knob is always off. when i first hooked it up to a power supply id current limited (PS was .75A max). Then it stopped drawing current. Seems indicative of the transistor frying.
-ted

Sounds like it... Try shorting (a pair of metallic tweezer work fine) across the emitter and collector (top and right pins if viewed as mounted, from the front, IIRC), ie +5V feed and the common track for the LEDs.
LEDs should light up to max, indepedent of dimming level set.

This is by memory and for the 3-button version of the knob board.

/Michael

indeed the exact fuse that was expected to blow was fried. i couldnt find a 1206 fuse at frys, and couldnt bear to be without my music for my upcoming roadtrip, so i jury-rigged an axial picofuse onto the pads. i guess it's better then the piece of wire i was thinking of using, but still not ideal. i'll have to order some fuses from digi-key.

now, on to the knob repair: i plan on troubleshooting that next week, but is there a part number for the transistor so i can get one ahead of time?

thanks for all the help
-ted

When doing button installs for BBS members, I just take my digital ohmeter, set it to 0-2000 ohms, and connect it to the three leads from the knob board as shown on Brian's site. My meter supplies enough current to power the LEDs, making for a quick and easy test of the board before sticking it on the display module.

Only once did it fail to work first try. In that case, I just applied more flux (using SMT flux pen) to EVERYTHING, and then remelted each solder pad again, one at a time. When done, I re-tested, and all was well.

Cheers

The transistor is Digikey part # 2SB709ACT