yet another Defender to switcher question

p1899m

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I am planning on putting a switcher in my defender. I have the switcher with wiring from Bob Roberts. I didn't get this from Bob so if any directions originally came with it I don't have them. Looks pretty straight forward. My question is more about the coin door lights and any other power to the coin door that would come from any connector on the original Linear PS other than 4J2. Actually I believe 4J3 from the linear PS originally powers the lights on the coin door.

Reading Bob's Williams coin door lamp circuit write up it sounds like you can disconnect 4J2 from the original linear PS and plug it to the connector from Bob's switcher to power the boards. As for the coin door lights, if I interpret this correctly Bob is saying I can still power them off the original 4J3 connector of the linear PS. Only difference is he suggests cutting the 27VDC line and putting a rubber band around the coin lockout to alleviate heat.

Does this sound like the correct way to set this up without causing any unwanted issues?

In the text in the lower right hand corner of this diagram Bob comments, "if using the linear, be sure to unplug the AC line to the switcher." I'm guessing he means if you are using the bypass he shows in the diagram and changing between either the linear or the switcher? Or am I wrong and he is saying you do not want to use the linear and the switcher together in the cab at the same time as I mentioned I was considering doing in my comment above?
wmslamps.jpg
 
That will fix the coin door light issue, but it won't stop the CMOS reset issues that occur with putting a switcher into Williams cabinets. I'm not going to beat this dead horse yet again. You can find a number of threads related to this.

If you need a rebuilt power supply or if you need your current one rebuilt, let me know. Then you will not have to deal with "work arounds".

ken
 
That will fix the coin door light issue, but it won't stop the CMOS reset issues that occur with putting a switcher into Williams cabinets. I'm not going to beat this dead horse yet again. You can find a number of threads related to this.

If you need a rebuilt power supply or if you need your current one rebuilt, let me know. Then you will not have to deal with "work arounds".

ken

Thanks Ken I appreciate reply and the offer to rebuild. I'm aware of the CMOS issues and if I wanted to could rebuild the PS myself. Not all that concerned with saving settings. If I were I would wire up an ATX like the one in my sinistar that I've had very few issues with. Really just want to wire the machine up and not damage anything in the process. I just want to play the game now and again. Even with the original PS and new batteries this machine only held it's settings for a very short time. So I never really had the luxury where this machine actually kept it's settings. On the other hand I had the bad luck of a rebuilt PS failing in my other defender and damaging the board set. I guess that scared me enough where I'm more concerned with protecting the board set rather than keeping the settings or the inconvenience of having to forward through the settings upon start up.
 
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I'm running that setup in my Defender right now. The switcher from Bob Roberts runs the boards, and the linear works the coin door lights and the coin lockout (I left mine working). One thing you'll need to do is connect the grounds of both power supplies together so everything has a common ground plane. The Defender power supply doesn't have overcurrent protection like the switcher does, but the later linear supplies do (Stargate and up). I'm thinking about either getting the Stargate addon overcurrent protector, or just changing over to a Joust/Robotron linear supply. BTW, if your batteries aren't lasting very long, it may help to replace your cmos - there was a thread on this recently (it was mainly about lithium conversions on Defender).
 
... The Defender power supply doesn't have overcurrent protection like the switcher does, but the later linear supplies do (Stargate and up). I'm thinking about either getting the Stargate addon overcurrent protector, or just changing over to a Joust/Robotron linear supply. .......

the add on board you are referring to, the "OVP" or "over voltage protection" board shown in the stargate manual, is apparently a p.i.t.a. (presumeably if is not quite right, dirty connectors etc)) - simpler just to get the robotron psu which has exactly the same circuit on the main board rather than as a separate board.
 
The only gotcha with dropping the later power supply in is that you have to make the cocktail power mod. Defender transformers only have the windings to support 12 pin connectors and the Joust on up transformers have an additional 6.3VAC set of windings to run the GI coin door lighting.

Not hard but if you don't, you'll be scratching your head wondering why no lightee.

ken
 
Thanks for all the tips, I was thinking the Stargate "OVP" board would be the easier way to go, but I'll pass on that one now. Thanks Ken for pointing out the cocktail power mod, I haven't seen that before. Is it as easy as plugging the 12 pin connector from the Defender transformer right onto the 15 pin header on the newer power supply, and adding jumpers w1-w3? If w1 (the jumper across resistor r27) is connected I'd think the voltage to the lights would be 9.1vac using the Defender transformer, is that too high?
 
Yeah, it really is that easy. You will need to add some standoffs because I don't think any of the old ones will line up with the newer power supply boards.

The voltage is a little high, but you can use a higher voltage bulb, I don't remember the number offhand. There is a 12V bayonet mount bulb, IIRC.

ken
 
Yeah, it really is that easy. You will need to add some standoffs because I don't think any of the old ones will line up with the newer power supply boards.

The voltage is a little high, but you can use a higher voltage bulb, I don't remember the number offhand. There is a 12V bayonet mount bulb, IIRC.
Cool, that cocktail mod is a neat trick! Thanks again Ken.
 
Thanks Ken for pointing out the cocktail power mod, I haven't seen that before. Is it as easy as plugging the 12 pin connector from the Defender transformer right onto the 15 pin header on the newer power supply, and adding jumpers w1-w3? If w1 (the jumper across resistor r27) is connected I'd think the voltage to the lights would be 9.1vac using the Defender transformer, is that too high?

The resistor is normally removed, but you can try it all three ways to see which gives the voltage you are looking for.
1) just W1 (R27 removed) should be 12V. You probably need higher voltage bulbs.
2) W1 + R27. Quick calculations say about 9V
3) Just R27. Quick calculations say about 6.9V

The only gotcha about the header is to either make sure the keying plug is in the 12 pin connector to make sure you plug it in the right way. Or replace it with a 15 pin and don't connect up the 14 & 15 wires. If you accidentally plug it in shifted down those 3 pins, you will not like the results. I burned up a 12 pin header doing just that. Now I make sure the keying plug is in to prevent accidental shorts.

ken
 
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