MSF Frankie's head servo issue??

RILaw

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I picked up a MSF with a non-working head on the creature. I replaced the servo with a NOS servo from a local hobby shop, with the correct wiring and black plug (94741 Same servo but the one I got is a waterproof model with a ball bearing motor, had a $59.95 sticker on it, got it for $20) . I installed it yesterday and the head still does not work. I see the LED on the servo board flash once on power up, but it does not light up during the servo test?? If I unplug then replug in the servo board harness I hear the servo run for have a second.

Any ideas?

Thanks in advance!
 
I haven't had any issues so I didn't check, but have you played a few games to make sure the head doesn't move? If I remember correctly *been a couple days* the head doesn't always move.
 
I haven't had any issues so I didn't check, but have you played a few games to make sure the head doesn't move? If I remember correctly *been a couple days* the head doesn't always move.

Played Many games, nothing.... And the servo test does nothing...

I have my Frankenstein in the shop right now, let me know if you want me to check anything.

Cool, but I have no clue what to check myself?? New servo, plugged in correctly with corresponding wires correct, nothing... LED on Servo board only flashes once on power up, nothing in servo test...
 
Are you certain you wired up the replacement servo correctly? I had to replace mine as well when I first picked it up, and if memory serves the wire colors did NOT match up with the original wires. This seems to be a pretty common issue with others who've replaced their servos.

Could be a problem with the servo board, but since it sounds like it's initializing properly, it wouldn't hurt to double-check the wiring.

If your original/bad servo was still making any noises or attempts to function, the servo board is probably working correctly; in my case, the gears were stripped out in the original, but it was still making noises at least.
 
Just looked at mine, the servo moves back and forth throughout the game, but I do NOT see an LED flashing on the monster board, maybe mine is bad?
 
Are you certain you wired up the replacement servo correctly? I had to replace mine as well when I first picked it up, and if memory serves the wire colors did NOT match up with the original wires. This seems to be a pretty common issue with others who've replaced their servos.

Could be a problem with the servo board, but since it sounds like it's initializing properly, it wouldn't hurt to double-check the wiring.

If your original/bad servo was still making any noises or attempts to function, the servo board is probably working correctly; in my case, the gears were stripped out in the original, but it was still making noises at least.

The wires are correct, its a NOS servo, not the newer model with the switched wires... Original had a fried motor (I took it apart to find that)...

Just looked at mine, the servo moves back and forth throughout the game, but I do NOT see an LED flashing on the monster board, maybe mine is bad?

Sounds like yours works fine, screw the led, lol.... Wish mine would move :( At least he throws the balls...
 
From the schematic:

On the servo board; pin 1 is +5, pin 2 is clock, pin 3 is data, pin 4 is enable, and pin 5 is ground - if you have activity on pins 2 through 4, the issue's probably on the servo board itself.

Pins 2 through 4 go through a few resistors & cap's, and into the PIC (the IC) on pins 17, 18, and 1 respectively - so look for activity there as well.

Looks like the clock is on pins 15 & 16 of the PIC, and output to the servo is on pin 6 (going to pin 1 of the servo). Pin 2 should be ground, and pin 3 should be +5 on that same servo connector.

The scanned version of the manual (at least the one I found) excludes this info; I'll try and get pictures and post them worst-case if the above doesn't help. Assuming you have a logic probe, the above should give you a better idea of what's up.
 
From the schematic:

On the servo board; pin 1 is +5, pin 2 is clock, pin 3 is data, pin 4 is enable, and pin 5 is ground - if you have activity on pins 2 through 4, the issue's probably on the servo board itself.

Pins 2 through 4 go through a few resistors & cap's, and into the PIC (the IC) on pins 17, 18, and 1 respectively - so look for activity there as well.

Looks like the clock is on pins 15 & 16 of the PIC, and output to the servo is on pin 6 (going to pin 1 of the servo). Pin 2 should be ground, and pin 3 should be +5 on that same servo connector.

The scanned version of the manual (at least the one I found) excludes this info; I'll try and get pictures and post them worst-case if the above doesn't help. Assuming you have a logic probe, the above should give you a better idea of what's up.

Thanks, I do have the manual and think that is on pg 93. I had a logic probe back in High School Robotics (That was almost 20yrs ago), I have no idea where it is, and if I did I have no clue how to use it anymore (Getting dumber by the day)... Sigh...

Thank You though, I may be screwed on this one....
 
If you can find it, or get a new one (typically under $25), they're very simple to use. Run the black connector to a ground connection, the red one to +5v DC, and check the points mentioned with the tip of the probe. They really do come in handy, and you'll figure it out in no time..
 
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