Looking for coil SA3-850-23-DC? Any ideas?

[JD]

Anyone know where I can get a coil for my 1979 Williams Gorgar drop targets part number SA3-850-23-DC as per manual?
I have tried pinballspareparts website and RTBB already.

Thanks J.D.

[FirePower]

I wouldn't be too paranoid about using the exact coil.  A 23-800 or 23-900 would also be ok. The 23 part is the wire gauge and the other number 850 in your case is the number of turns. The 23-800 will have slightly  more "punch"   If you get a 23-900 and wanted to you could unwind 50 turns, but I wouldn't bother - particularly for a drop target reset.

WMS used anything from 23-750 to 23-900 on various sys3-6 machines I've got, all with the same driver board and to be honest I can't pick any difference in game play.  I try to make sure that slings and bumper groups use the same coils, but don't really think it matters that much.

Make sure you have the diode on it for DC use, correctly orientated - banded end to positive,  and find out why the original coil failed in the first place so you don't stuff another one.

[JD]

I wouldn't be too paranoid about using the exact coil.  A 23-800 or 23-900 would also be ok. The 23 part is the wire gauge and the other number 850 in your case is the number of turns. The 23-800 will have slightly  more "punch"   If you get a 23-900 and wanted to you could unwind 50 turns, but I wouldn't bother - particularly for a drop target reset.

WMS used anything from 23-750 to 23-900 on various sys3-6 machines I've got, all with the same driver board and to be honest I can't pick any difference in game play.  I try to make sure that slings and bumper groups use the same coils, but don't really think it matters that much.

Make sure you have the diode on it for DC use, correctly orientated - banded end to positive,  and find out why the original coil failed in the first place so you don't stuff another one.

Thanks firepower. Will source 23-750 to 23-900.

Cheers

J.D.

[JD]

So Firepower or others? Are the SA3 letters critical too? I assume the DC means you need a diode?
 
Will any of these do the job?

AE-23-800
AE-23-800-2
SGI-23850-DC
SA3-23-900-DC

[pinnies4me]

So Firepower or others? Are the SA3 letters critical too? I assume the DC means you need a diode?
 
Will any of these do the job?

AE-23-800
AE-23-800-2
SGI-23850-DC
SA3-23-900-DC

From http://www.pinballmedic.net/coil_chart.html -

Williams Old Coil Number to New Coil Part Number Cross-Reference Chart
SA-23-850DC ~ AE-23-800-01
SA3-23-850DC ~ AE-23-800-04
SA2-23-850DC ~ AE-23-800-05
SG-23-850DC ~ AE-23-800-06
SA4-23-850DC ~ AE-23-800-07

[FirePower]

Are the SA3 letters critical too? I assume the DC means you need a diode?
 

Yes the DC means with a diode - when a DC coil de-enrgises it induces a back spike of voltage and the diode prevents this from finding it's way back into the driver circuit.

I've read the pinmedic site and other places where it says the first bit of the coil desigantion is for the physical arrangement. I've looked at "a fair few" and they all look to be wound on the same former to me. I looked pretty hard on my Flash ones because I stripped the wrappers off and scrubbed and cleaned them before rewrapping them. The only differences I've noticed are that drop target coils tend to have the diodes mounted on the outside end ie the other side to the winding, most others seem to have the diode on the top side closest to the coil windings.  If I had to guess I'd say maybe someone is kidding themselves it's a vibration idea .....

It doesn't show that well but in the picture the middle coil has the diode on the top side the left coil which looks like it has no diode actually has the diode on the outside to the left of the picture if that clarifies what I've said above

If it physically fits, which I reckon all will,  I'd say it's ok.  JD, all else being equal I'd go the 23-850 from your list.
 

[Boots]

So Firepower or others? Are the SA3 letters critical too? I assume the DC means you need a diode?
 
Will any of these do the job?

AE-23-800
AE-23-800-2
SGI-23850-DC
SA3-23-900-DC

The first two coils are the same package with different diode setup.
23-850 and 23-900 are slightly less powerful but will also run slightly cooler.
I think those old machines are pretty forgiving, just if the coil is doing a lot of work it may pay to go to a 23-900 so it runs a bit cooler (with slightly less power)
If you went for 23-850 in general you would be pretty safe though.
You can use any Williams coil with the same wire gauge (23) & number of turns (800, or 850, or 900), just make sure the diode is on there and band to the positive.

[JD]

Thanks Firepower and boots. Appreciate your help.

I have it now and will arrange the new coil and get Ken, Skybeu to check the boards as I understand it may have taken out the transistor too.

Many thanks to all.

J.D.