7 Segment LED display problem - air hockey scoreboard

Dodgydave

Joined Jun 22, 2012
9,691
You can narrow it down faster by using a flat blade screwdriver and temporary shorting the C/E pins of the 100 ohms transistors, one by one when the display shows zeros, the faulty segment should light up,

if it does the fault is from the transistor to the chip,

if it doesn't its from the transistor to the display.
 

Thread Starter

chadecoen

Joined Oct 14, 2015
14
Can I get a suggestion on the correct transistor to buy to replace mine? Was looking at amazon but I'm not sure which one is correct. Same with 100 ohm resistors. Any suggestions? Is Amazon even ok to buy from?

BTW, I think I found the culprit?
 
Last edited:

Thread Starter

chadecoen

Joined Oct 14, 2015
14
Thanks AK. I'm in GA. Just outside Atlanta.

And is a 100 ohm resistor a 100 ohm resistor or is there any specifics I should look for?
 

AnalogKid

Joined Aug 1, 2013
8,708
There is nothing special about any of the components on this board. Any general purpose resistors, caps, and transistors will work. If you're in a hurry, Radio Shack has a 15-pack of PNP's for $3.50, Catalog #: 2761604.

Or I can mail you some. I got lots.

ak
 

Thread Starter

chadecoen

Joined Oct 14, 2015
14
Thanks again AK. I would imagine anyone who has ever ordered has extra! 100 packs online for a couple bucks, that's crazy affordable. I appreciate it but I think you are right. Prolly easiest to just stop by the Shack today while running around.

Thanks for all of y'alls help with this. Super excited to see if I can rescue it after all is said and done.
 

Thread Starter

chadecoen

Joined Oct 14, 2015
14
Also, if you move on to replace parts, DONT OVER HEAT THE PCB. these boards are not really meant for rework and the copper pads can come loose from the board when heated too much and then you have a real mess. If you don't have one, use a temp controlled soldering pencil and solder wick to remove solder or a good solder sucker/desoldering station (re-work station)
Well I promised an update and despite GopherT's best advise, I really screwed up the traces on the board. Anyone willing to charge me to build it over or fix my mess somehow? It's just too delicate for me. I had high hopes but I think someone with more experience and the proper tools would have better luck. Any ideas? I really appreciate all the help getting me to here everyone.

Chad
 

Thread Starter

chadecoen

Joined Oct 14, 2015
14
Thanks Brevor, GopherT has already re-invented the wheel on this and thinks mine may be similar to his and is willing to check it out. If it doesn't work out I'd be very grateful for your help. THANK YOU!

Chad
 

rburggraf

Joined Oct 9, 2017
1
I know this thread is over 1 year old, but I think you are my only hope. I bought a Classic Sport 788 Air hockey table with a score board that looks exactly like this thread. The display is dim and has missing display segments. Trouble is they quit making this display in 1999, there are no manuals or anything. If you think you might be able to fix it, I'll pay for your time and parts. There just is no other way for me to get this fixed.
 

GopherT

Joined Nov 23, 2012
8,012
I know this thread is over 1 year old, but I think you are my only hope. I bought a Classic Sport 788 Air hockey table with a score board that looks exactly like this thread. The display is dim and has missing display segments. Trouble is they quit making this display in 1999, there are no manuals or anything. If you think you might be able to fix it, I'll pay for your time and parts. There just is no other way for me to get this fixed.
Check your inbox on the upper right corner of this page...
 
Hi guys!! Hopefully someone is still around and maybe can answer a few questions for me.
I bought the classic sport air hockey table. Same score board as in this post. I get power to the board. Same segments are out on all numbers. The bottom of all the zeros. All the times are lit up. No sound or light from the bottom. And no score. No matter what.
Could you maybe tell me what I am looking for? And/or if anyone can repair it for me?

Thanks so much for any help!!
 
Check your inbox on the upper right corner of this page...
Hi GopherT, I'm having the same problem as the others here with the Classic Sport air hockey scoreboard. We purchased the table for our Kids Play Zone at church, but the scoreboard only partially works. Would you be wiling to take a look at it for us?
 

dl324

Joined Mar 30, 2015
11,928
Welcome to AAC!
Hi GopherT, I'm having the same problem as the others here with the Classic Sport air hockey scoreboard. We purchased the table for our Kids Play Zone at church, but the scoreboard only partially works. Would you be wiling to take a look at it for us?
I believe GopherT has left the forum.

If you post more information, someone else might be able to help. A schematic would be most helpful.
 
So I have the same scoreboard but mine is for a Classic rod hockey table I'm fixing up. Some of the wires were messed with and I'm wondering if someone in the past "fried" the board.. but I'm hoping I can fix it.. Now I have little to no circuit work but (outside of wiring a old fire detector to be a water alarm) I'm willing to try. When 6v power supply connected only the 10 min light kind of comes on and the top horizontal line and the left top vertical line in the lcd come on for each number. Any help would be appreciated!
 
Top