Tech: Mav paddle wheel optos

[LexingtonVAPin]

I had a Mav for 15 years. I fixed the paddle wheel opto problem by installing ’super’ raw optos from The Pinball Lizard.

Lizard is not active anymore. A museum where I volunteer just got a donated Mav. Same issue with the paddle wheel optos. I replaced with raw optos of the type that DE Sega Stern use that are the same for transmitter and receiver, MV8114 but no luck.

Any suggestions? I would like to keep the optos rather than go to a mechanical switch.

Can I sub WPC style UV transmitter/ receiver?

https://groups.google.com/g/rec.games.pinball/c/Si0xHFLRLQs/m/TAueGIVUFhEJ

[Kerry Imming]

I can't find a schematic for the 520-5102-00 and 520-5103-00 opto tx/rx
boards, but I did find a picture here:
https://www.ebay.com/itm/321971676030

The WPC ones are just the LEDs so I doubt they will work.

I'd just buy the ebay assemblies, but if you want a pointer to some
Tx/Rx opto-led components I can try to find some for you.

- Kerry

[LexingtonVAPin]

Thanks for that, Kerry. It is good to know those are on eBay. I will
recommend that the museum get a couple pair for stock and maybe pick up
some for me. I believe they are used on Whitestar games, too. And
perhaps some Sterns after Whitestar.

I was referring to the raw optos. Those used in Sega/Stern are the
MV8114 and they are used in both the transmitter boards and receivers.
I thought I heard somewhere that they are not as sensitive as dedicated
transmitter LEDs and photo diodes?

WPC uses QED123 as the transmitter and QED124 as the receiver in the
opto boards.

My memory on the optos I got ~20 years ago from The Pinball Lizard is
incomplete. I think I got them and put them into the Mav and they
locked in and I didn't have an issue for the 15 years I had that pin.
Sega/Stern recommended abandoning the optos and installing a reed switch
which is hard to find.

I think, maybe, I then used the rest of those opto diodes I got from
Lizard in a slew of pins, including WPCs. When I ran out, I got my
supply from GPE.

I do not remember if the ones I installed in Mav were visible or not.
The original Sega/Stern are. Of course, the WPC are IR.

They the were not so hard to get to, I would just slap in a pair of
QED123 / QED124 into the Sega opto boards on Mav to see if they work.

I got the optos in the Mav working, for now, with replacement MV8114 in
both the transmitter and receiver.

--
http://orcalcoast.com/

[Kerry Imming]

I'm glad you got it working.

I wish I understood optoelectronic devices better. There must be an
advantage (like sensitivity) in having dedicated transmitter and
receiver devices. I remember being surprised when I learned that Stern
used the same device for transmitter and receiver. It obviously works
well enough and I can appreciate the cost advantages of the common parts.

- Kerry

[LexingtonVAPin]

Dang, meant IR.

I found the paperwork from 'The Pinball Lizard'. The optos I received
are IR transmitter and photodiode receiver.

I think I installed them in the DE/Sega Mav, if my memory is correct.

--
http://orcalcoast.com/