I have been having a real hard time with this particular pcb and am stuck.
This is a sensor for a little game called Mini Dunx by ICE GAME. It is a redemption game where little kids throw small basketballs through a hoop and score points. There is an IR Transmitter on one end of the basket and a two receivers on the other end. Very simple but I can't figure out what is wrong.
The IR sensors are working. They go to a op amp and from there to the Inverters shown in the schematic. I didn't include the Op Amp schematic because it seems to be working like it should. With the transmitter not shining into the receiver I get 5Volts at the input into the inverter. When I shin the transmitter into the receiver the 5volt drops to 0 volts at the input into the first pair of inverters but at the output nothing happens.
That is the problem, why don't I get a voltage change at the output of the first pair of inverters? And why doesn't the LED turn on and off?
The IR pcb is linked to the main board by that sense line and once it reaches the main board it goes through those 10K resistor network and into a 74hc165. Which seems to be OK.
When I disconnect the sense line I get 5 volts on the main pcb at that 10K resistor network. When that goes to zero the games scores a point. But when I hook that sense line back up to the IR pcb the 5 volts drops to 0 volts and stays there regardless of the transmitter being on or off.
I also checked all of those parts on the schematic out of circuit and they all check OK? Unless I missed something. I replaced the hex inverter a 74LS05 and it made no difference.
Any ideas on what is going on?
Can someone explain how this should work.
Thanks very much,
Russ
This is a sensor for a little game called Mini Dunx by ICE GAME. It is a redemption game where little kids throw small basketballs through a hoop and score points. There is an IR Transmitter on one end of the basket and a two receivers on the other end. Very simple but I can't figure out what is wrong.
The IR sensors are working. They go to a op amp and from there to the Inverters shown in the schematic. I didn't include the Op Amp schematic because it seems to be working like it should. With the transmitter not shining into the receiver I get 5Volts at the input into the inverter. When I shin the transmitter into the receiver the 5volt drops to 0 volts at the input into the first pair of inverters but at the output nothing happens.
That is the problem, why don't I get a voltage change at the output of the first pair of inverters? And why doesn't the LED turn on and off?
The IR pcb is linked to the main board by that sense line and once it reaches the main board it goes through those 10K resistor network and into a 74hc165. Which seems to be OK.
When I disconnect the sense line I get 5 volts on the main pcb at that 10K resistor network. When that goes to zero the games scores a point. But when I hook that sense line back up to the IR pcb the 5 volts drops to 0 volts and stays there regardless of the transmitter being on or off.
I also checked all of those parts on the schematic out of circuit and they all check OK? Unless I missed something. I replaced the hex inverter a 74LS05 and it made no difference.
Any ideas on what is going on?
Can someone explain how this should work.
Thanks very much,
Russ
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