Bullwinkle
Member
Evel Knievel solenoids pull when in test mode..but not during game
I've just put a new (to me) MPU -35 into an Evel Knievel I'm working on (originally MPU -17). The 35 was tested working as a playboy mpu prior to this use. I'm using 2732 eproms, so I did the jumpers listed on pinrepair for using 2732s:
e4 to e13a
e12 to GND
e7 to e8
e10 to e11
e31 to e32
e16a to e29
e33 to e35
I removed all other jumpers. The board itself gives the 7 flashes and then boots up with displays. I can also cycle through the lights test, display tests and solenoids test.
The problem I'm having is, during test mode, it will cycle through all solenoid tests successfully (pop bumpers pop and slingshot bumpers kick). But when I fire up a game, the pops and slingshots are dead as well as a few other items on the playfield. flippers work as do the targets and the sol that resets them. I've checked the transistors on the driver board with a DMM and they all show as good (check with power off, negative to the tab, positive to each leg, DMM in diode mode, middle giving 0 and outer legs giving approximately 5.5)
I'm pretty sure I need to do some work on the solenoid driver board's HV section as the displays tend to become garbled, followed by a hum and then a click, then they display proper digits for another minute or so and the hum/click cycle continues. Not sure if this would affect the solenoids though.
Just curious as to why they would function in test mode but not game play. Any help or suggestions are appreciated. I'll be doing all the suggested upgrades to the solenoid driver board.
Thanks,
Tom
I've just put a new (to me) MPU -35 into an Evel Knievel I'm working on (originally MPU -17). The 35 was tested working as a playboy mpu prior to this use. I'm using 2732 eproms, so I did the jumpers listed on pinrepair for using 2732s:
e4 to e13a
e12 to GND
e7 to e8
e10 to e11
e31 to e32
e16a to e29
e33 to e35
I removed all other jumpers. The board itself gives the 7 flashes and then boots up with displays. I can also cycle through the lights test, display tests and solenoids test.
The problem I'm having is, during test mode, it will cycle through all solenoid tests successfully (pop bumpers pop and slingshot bumpers kick). But when I fire up a game, the pops and slingshots are dead as well as a few other items on the playfield. flippers work as do the targets and the sol that resets them. I've checked the transistors on the driver board with a DMM and they all show as good (check with power off, negative to the tab, positive to each leg, DMM in diode mode, middle giving 0 and outer legs giving approximately 5.5)
I'm pretty sure I need to do some work on the solenoid driver board's HV section as the displays tend to become garbled, followed by a hum and then a click, then they display proper digits for another minute or so and the hum/click cycle continues. Not sure if this would affect the solenoids though.
Just curious as to why they would function in test mode but not game play. Any help or suggestions are appreciated. I'll be doing all the suggested upgrades to the solenoid driver board.
Thanks,
Tom