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Title: Need help and schematic on Universal Ultra series sound card Post by: startek2 on August 14, 2012, 08:48:52 PM I have come to the mountain in hopes of enlightenment....I have a ultra series machine and there is no sound.....I opened up the sound box and I saw a chip with a big hole in it.....I replaced it (ULN8203AN) and still no joy....again I looked closer at the board and found a shorted diode I assume it was a 1N914 (guessing). I replaced it, sounded better when the game came on but still no joy....I am assuming I blew out the chip I replaced because I hadn't spotted that shorted diode. I have ordered some more chips however....although this is not a large board and I suppose I could sit down and draw out a diagram, does anyone here have a schematic for this infernal thing?? Thanks oh great slot tech gurus in advance!!
Title: Re: Need help and schematic on Universal Ultra series sound card Post by: jbshocks on August 14, 2012, 10:38:24 PM Sound out on an ultra is very common. The cure is not yet documented. Can you please share the position of chip and the diode? You said that the machine sounds better? Does that means it now makes some sound?
Title: Re: Need help and schematic on Universal Ultra series sound card Post by: jbshocks on August 14, 2012, 10:42:05 PM I just noticed that you said that you opened the sound box, Is that where the chip you replaced is located? The sound trouble is typically on the MPU. I would suggest testing the board in working machine. I don't see a location in your profile there may be a uni owner near you. I am in SE Michigan and would test your board for you.
Title: Re: Need help and schematic on Universal Ultra series sound card Post by: startek2 on August 14, 2012, 10:49:16 PM thanks for responding....i had the cpu sent out for repair and verified there is sound coming out of it....when i get back to the shop i will verify that with my o-scope....but i was hoping for a schematic if you have one as it is a simple board......i have read in another thread the sound chips tend to go bad but that is all i know for now.....akk i will have some better descriptions when i get back to it......but ya there was definitely ia shorted diode...(one of 4) i don't know if it is being used in a bridge circuit or some kind of phaze or noise circuit, that is why i need a schematic.....but i will definitely post my findings here. this is the chip opposite the actual amplifier on the opposite edge of the sound card.
Title: Re: Need help and schematic on Universal Ultra series sound card Post by: uniman on August 15, 2012, 12:54:04 AM Jbshocks is right, most sound trouble is on the mpu, but I have had at least one bad sound card.
I have several spare sound cards, if your looking for one give me a pm. No known schematics for that card. Jim |