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arcadus
26th July 2009, 10:57 AM
Several people have asked me how an EM gun works, so I have posted here.
The game is a Super Circus circa 1969.

The gun is mounted on a gymbal with a rod protruding perpendicularly through the bottom.
Attached is a springloaded horizontal arm with a stylus at the end.
The stylus rubs against a board with brass rivets set in corresponding to the targets.
When the active target is lined up correctly, contact is made between stylus and rivet, operating target hit relay.
The board can be adjusted for accuracy.

The large coil seen above the board is attached to the rod and gives "feedback" when the trigger is pulled, like a large version of a pinnie knocker.

Ballywannabe
26th July 2009, 11:03 AM
Thanks for that - very interesting:)

So simple yet effective - as usual relied on the op's maintaining it if it was to operate correctly - I am sure I played some that were 'off' aim' back in the day:blink:

David_AVD
26th July 2009, 11:05 AM
They're fascinating to look inside aren't they. As a kid I had no idea how they worked so it's always interesting to see inside them now. The mirror and vertical play field is quite neat.

I gather that you can't just hold the trigger and randomly roam the gun all over the place in the hope of hitting a target. I'm guessing that the target needs to line up (moving stylus on correct rivet) before you pull the trigger?

arcadus
26th July 2009, 11:22 AM
I gather that you can't just hold the trigger and randomly roam the gun all over the place in the hope of hitting a target. I'm guessing that the target needs to line up (moving stylus on correct rivet) before you pull the trigger?

With this game it's a one shot trigger.
The stylus and rivet have to be lined up on an active target when trigger is pulled.
If it misses, the shot count increments and resets for another shot.

You can cheat by knowing the sequence of the targets and being in the general area of the next target.

terry007
26th July 2009, 01:34 PM
Nice work Ralph. I learn something new everyday!

stuba
29th July 2009, 10:34 AM
wow! and holy crap!

i have this game in my shed and the gun has been ripped out of it leaving a mass of broken wiring. I have a spare gun (from a chicago coin rifle scope) but its a project that scares me until I saw that you have one arcadus! I need some detailed pics of the wiring under the gun deck, i'll PM you about it.

i am daring to hope that the version you have also has the 8-track tape sound effects? I have a tape player and there is a twisted mass of tape that has broken around it..

I have a full set of schematics if you need them?

and great info on how the gun works - thanks for posting :-)

arcadus
29th July 2009, 11:21 AM
Great news to see another one around!
Mine is missing the tape player but has speaker and wiring for it. I have one to put in.
Can't find soundtrack for it anywhere (was going to record circus music) but if you can extract that tape, I have an 8track player and recorder, perhaps we could make a couple of recordings?
I have the schematics and photos will be no problem.:)

stuba
29th July 2009, 12:30 PM
I think the tape may be able to be repaired, will make some enquiries. be more than happy to have it duplicated/extracted.

The cool thing about this game was that one of the speakers was mounted in the gun itself so its close to the players ear as he shoots. with a replacement gun i don't have this option but would be keen to see some detailed pics on how they did that as well. maybe it will be possible to replicate.

its really great to see another one :)

dj10555
29th July 2009, 03:47 PM
It's not hard to repair the tapes if you have the patience to unwind it all. Most of the times its just the change splice which has come off or the foam pads have worn down.

There's a chance that Mark Clayton on the site below may have a recording.
http://arcadearchive.com/em/

Or you can buy the 8 track parts from
http://www.katestrackshack.com/suppliesforsale.htm.
They also repair broken tapes if necessary.


regards Derek

stuba
29th July 2009, 04:04 PM
cheers Derek

I have emailed Mark twice in the last couple of months but had no reply. :unsure Super circus seemed to be one of the machines that he was looking for audio for.

thanks for the other link, that will come in handy.

Virgil Tracy
29th July 2009, 05:46 PM
.

There's a chance that Mark Clayton on the site below may have a recording.
http://arcadearchive.com/em/



I am not sure how often he updates the site but the 8 track for Flying Ducks has been pending for a long time

arcadus
30th July 2009, 11:14 AM
Another thing with EM 8track tapes is that they have to be spliced without the metallic track changer splice.

AskJacob
30th July 2009, 01:43 PM
mmm perhaps a solid state drop in replacement may be on the cards.

I have seen some on offer out there, my playing with the vmusic modules gives me ideas too :D

Do many of the 8 track units use all 8 tracks in game? I think I saw a few that used only 2 or 4, the remaining tracks were "switchable" by moving the heads, to be used when the 1st set of tracks got worn out...

OK that link was the site I browsed years ago. So wild kingdom was a 1 track game, but switchable from 4 recorded tracks. Hmm

Cheers
Jacob

arcadus
30th July 2009, 07:52 PM
I think the earlier EMs with only two sounds used track 1. I know "spin out" is only recorded on track 1.
The outputs of the left and right track are switched to give two sounds.
The Sega "Monte Carlo" has four sounds but uses a modified player to output all sounds simultaneously then switches those.
.