Catacomb MCR106 problem

[infrared pinball]

Hello i have a Stern Catacomb with Lamp driver problem.

I tested all the mcr106 and 2n5060 with multimeter in diode function and
the most of them reads 0.7 (black in C, red in G) and 1.8 when inverted.

for example with Q47 (MCR106) does not get this values and the lamp of course is not working.

I test continuity on the cables, connectors and the lamp socket and it is ok.

I buy some MCR106 with part number ON CR106-6G so i change the MCR in Q47 but the lamp still not working.
So i check the multimeter and i get only 0.7 and NOT 1.8 but 0 when black in G and red in C.
I also tested a new mcr106 out off the circuit and reads the same 0.7 and NO 1.8. Black in G, red in C reads nothing.
Does this MCRs is faulty or does not the right part number ?

Thanks
Michael

[[e-mail]]

Post by infrared pinball
Hello i have a Stern Catacomb with Lamp driver problem.
I tested all the mcr106 and 2n5060 with multimeter in diode function and
the most of them reads 0.7 (black in C, red in G) and 1.8 when inverted.
for example with Q47 (MCR106) does not get this values and the lamp of course is not working.
I test continuity on the cables, connectors and the lamp socket and it is ok.
I buy some MCR106 with part number ON CR106-6G so i change the MCR in Q47 but the lamp still not working.
So i check the multimeter and i get only 0.7 and NOT 1.8 but 0 when black in G and red in C.
I also tested a new mcr106 out off the circuit and reads the same 0.7 and NO 1.8. Black in G, red in C reads nothing.
Does this MCRs is faulty or does not the right part number ?
Thanks
Michael

MCR106 are not transistors. They are Silicon Controlled Rectifiers SCRs. They are essentially two transistors tied together so that they do not conduct until a voltage is applied to the gate - the control pin. Once the voltage is applied, the SCR continues to conduct as long as the current is flowing through it, even after the gate voltage is turned off. The only way I know to test it is in a live circuit.

Before you start this, have you done the basic tests on the lamp socket and bulb? With the game in lamp test mode, jumper from the tit on the end of the socket to a tit on a working light bulb. If the bulb does not light, either the bulb or the socket are bad.
If the bulb lights, ground the output leg of the q47 SCR. If the bulb does not light, you may have a broken solder joint on the light driver board. Bulb, socket, and solder joint are the three most likely causes of a light not burning. If the light worked in all cases, put a jumper from 5 volts to the driver resistor. In this case, that is R47. Make the connection on the side of the transistor that connects to the MUX chip. If the bulb comes on, your SCR is good, but your MUX may be bad. That is a more complicated test because Bally did not provide a way to test a single bulb at a time.

Good luck
pinworks

[infrared pinball]

Post by infrared pinball
Hello i have a Stern Catacomb with Lamp driver problem.
I tested all the mcr106 and 2n5060 with multimeter in diode function and
the most of them reads 0.7 (black in C, red in G) and 1.8 when inverted.
for example with Q47 (MCR106) does not get this values and the lamp of course is not working.
I test continuity on the cables, connectors and the lamp socket and it is ok.
I buy some MCR106 with part number ON CR106-6G so i change the MCR in Q47 but the lamp still not working.
So i check the multimeter and i get only 0.7 and NOT 1.8 but 0 when black in G and red in C.
I also tested a new mcr106 out off the circuit and reads the same 0.7 and NO 1.8. Black in G, red in C reads nothing.
Does this MCRs is faulty or does not the right part number ?
Thanks
Michael

MCR106 are not transistors. They are Silicon Controlled Rectifiers SCRs. They are essentially two transistors tied together so that they do not conduct until a voltage is applied to the gate - the control pin. Once the voltage is applied, the SCR continues to conduct as long as the current is flowing through it, even after the gate voltage is turned off. The only way I know to test it is in a live circuit.
Before you start this, have you done the basic tests on the lamp socket and bulb? With the game in lamp test mode, jumper from the tit on the end of the socket to a tit on a working light bulb. If the bulb does not light, either the bulb or the socket are bad.
If the bulb lights, ground the output leg of the q47 SCR. If the bulb does not light, you may have a broken solder joint on the light driver board. Bulb, socket, and solder joint are the three most likely causes of a light not burning. If the light worked in all cases, put a jumper from 5 volts to the driver resistor. In this case, that is R47. Make the connection on the side of the transistor that connects to the MUX chip. If the bulb comes on, your SCR is good, but your MUX may be bad. That is a more complicated test because Bally did not provide a way to test a single bulb at a time.
Good luck
pinworks

Thanks for your answer i will test what you have suggested tomorrow and reply.
But i have one question:
if the SCR stays on when the gate voltage turned off from output pin of 4514 how the lamp driver turn off the lamp ?

Thanks
Michael

[seymour.shabow]

Post by infrared pinball
if the SCR stays on when the gate voltage turned off from output pin of 4514 how the lamp driver turn off the lamp ?

Turns off automatically at AC zero crossing (SCR is switching AC, not DC)

The DC voltage has to be reapplied at zero cross via the 4514 latch to
the gate.

[infrared pinball]

Post by seymour.shabow

Post by infrared pinball
if the SCR stays on when the gate voltage turned off from output pin of 4514 how the lamp driver turn off the lamp ?

Turns off automatically at AC zero crossing (SCR is switching AC, not DC)
The DC voltage has to be reapplied at zero cross via the 4514 latch to
the gate.

ok thats explain all

thank you
Michael