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Help identifying a replacement transistor

idahoskier

Registered
Joined
Feb 21, 2021
Messages
5
Location
Idaho
Looking for some help finding a suitable replacement transistor in my 1977 Mattel Las Vegas machine. I know virtually nothing about this stuff, but can solder, and have identified that the existing one has had the leads broken off. It is used to switch the flipper coil. I have searched and can find no replacement or cross reference for the existing RCA unit. I have tried a TIP120 and the flipper will activate but will trip the breaker if trying to hold the flipper on. Any help would be appreciated. TIA.
20210220_185148.jpg

Link to the schematic:
https://pinwiki.com/wiki/images/8/85/LasVegas_schematic.pdf
 
Thanks for the replies. It is true that the schematic does not show the transistor. Perhaps this will help clarify it? From pinwiki:
Some Las Vegas pinball machines came with an alternate flipper coil assembly which consisted of a Dormeyer 1/2" stack laminated 24 volt AC solenoid. Dormeyer part number 1504-M-1. It has a coil resistance of 2.3 ohms and can draw up to 9 amps current. Even though this solenoid is designed for 24 volts AC operation, this machine operates it on 24 to 30 volts (approximate) DC.

Regardless of which flipper unit assembly was installed in your machine, one solenoid operates two flippers via a connecting rod/linkage. Both the standard flipper unit and the alternate (Dormeyer) flipper unit have high wattage resistors connected to the coils through the end-of-stroke (E.O.S. ) switches. When the EOS switch is closed, full power is applied to the coil. The coil moves the linkage to open the EOS switch which cuts in the resistors to limit the current to the coil to prevent the coil from burning up. The coil is rated for intermittent duty only.
 
The 2N6667G that David listed is capable of 10A and up to 60V so it's probably the correct one given that it's used elsewhere in the game.

Pictures might help confirm this, other working coil presumably has the transistor still connected?
 
This is definitely one to be filed under careful of what you ask for...!!! o_O

A couple of pictures from different angles are most certainly needed. From this angle it looks like the middle leg of the transistor is not connected. It looks a mess, if the game was in my possession I'd be drawing a new schematic to help identify all the components missing from the game schematic.
 
Information for this game is lacking so perhaps this will help someone in the future. The 2n6667g will be here tomorrow so I will see if that works. It is messy.... but this is a game built by a toy company that never built a pinball machine before this or after it. Drawing a new schematic is above my pay grade;)20210225_072718.jpg
20210225_072655.jpg
 
So I am happy to report that the 2n6667g works as intended. Now I face the issue of replacing the Dormeyer 1504-M-1 solenoid (description in previous post) since the flipper on the other side is now sticking in the closed position. Any suggestions for a replacement? 😁
 
OMG, that is the most bodgy circuit I have ever seen - and to think it was sold "commercially"! Any school kid electronic hobbyist could do better than that. Amazing.
 
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