From Newsgroup: rec.games.pinball

This is for a 1958 Gottlieb Roto Pool I am helping with.
I thought the A-9735 coil was a substitute for the obsolete R20-4 coil.

This is both from the very useful flippers.com Coil Resistance Chart: https://www.flippers.com/coil-resistance.html
and places selling coils online.

The game owner says the A-9735 is 1/16" longer than the original R20-4
coil. Is this expected? Is there a way to make the A-9735 work in the
relay? For example, can the coil core be filed down?

- Kerry
--- Synchronet 3.19a-Win32 NewsLink 1.113

From Newsgroup: rec.games.pinball

On 2022/11/13 7:07 a.m., Kerry Imming wrote:

This is for a 1958 Gottlieb Roto Pool I am helping with.
I thought the A-9735 coil was a substitute for the obsolete R20-4 coil.

This is both from the very useful flippers.com Coil Resistance Chart: https://www.flippers.com/coil-resistance.html
and places selling coils online.

The game owner says the A-9735 is 1/16" longer than the original R20-4 coil.  Is this expected?  Is there a way to make the A-9735 work in the relay?  For example, can the coil core be filed down?

- Kerry

Hi Kerry,

I don't have dimensions of the coils on flippers because that would be
too much like work!

That being said I guess when things like this come up I should add the
height of coils that people notice, so if folks want to send me just the
total height of the body of the coil I will add a column for that added dimension.

I do know that there are Europeans making new coils and they are metric,
and don't always fit properly...where did you get the A-9735 coil from?

And as for fitting, is this a relay or an action coil? If an action coil
there are coil holders that have slots for the front hole so they can be adjusted for off-size coils, otherwise I think you can file the sucker...

John :-#)#
--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
#7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

--- Synchronet 3.19a-Win32 NewsLink 1.113

From Newsgroup: rec.games.pinball

On 11/13/2022 5:26 PM, John Robertson wrote:

On 2022/11/13 7:07 a.m., Kerry Imming wrote:

This is for a 1958 Gottlieb Roto Pool I am helping with.
I thought the A-9735 coil was a substitute for the obsolete R20-4 coil.

This is both from the very useful flippers.com Coil Resistance Chart:
https://www.flippers.com/coil-resistance.html
and places selling coils online.

The game owner says the A-9735 is 1/16" longer than the original R20-4
coil.  Is this expected?  Is there a way to make the A-9735 work in
the relay?  For example, can the coil core be filed down?

- Kerry

Hi Kerry,

I don't have dimensions of the coils on flippers because that would be
too much like work!

That being said I guess when things like this come up I should add the height of coils that people notice, so if folks want to send me just the total height of the body of the coil I will add a column for that added dimension.

I do know that there are Europeans making new coils and they are metric,
and don't always fit properly...where did you get the A-9735 coil from?

And as for fitting, is this a relay or an action coil? If an action coil there are coil holders that have slots for the front hole so they can be adjusted for off-size coils, otherwise I think you can file the sucker...

John :-#)#

Hi John,
Thanks for your follow up. I did not mean to imply that your chart
should be changed, just pointing out that it's very useful. Thanks for keeping that posted.

This is a relay coil. I'm helping someone who sent me an email question
about where to get an R20-4 coil. Searching for R20-4 coil turns up
lots of places selling the A-9735 as a substitute so I assumed this was
just a naming or insignificant resistance difference.

I'll see if he can file it down to fit. I wanted to check here first to
see if there was any experience with this problem.

- Kerry
--- Synchronet 3.19a-Win32 NewsLink 1.113

From Newsgroup: rec.games.pinball

On 2022/11/14 5:32 a.m., Kerry Imming wrote:

On 11/13/2022 5:26 PM, John Robertson wrote:

On 2022/11/13 7:07 a.m., Kerry Imming wrote:

This is for a 1958 Gottlieb Roto Pool I am helping with.
I thought the A-9735 coil was a substitute for the obsolete R20-4 coil.

This is both from the very useful flippers.com Coil Resistance Chart:
https://www.flippers.com/coil-resistance.html
and places selling coils online.

The game owner says the A-9735 is 1/16" longer than the original
R20-4 coil.  Is this expected?  Is there a way to make the A-9735
work in the relay?  For example, can the coil core be filed down?

- Kerry

Hi Kerry,

I don't have dimensions of the coils on flippers because that would be
too much like work!

That being said I guess when things like this come up I should add the
height of coils that people notice, so if folks want to send me just
the total height of the body of the coil I will add a column for that
added dimension.

I do know that there are Europeans making new coils and they are
metric, and don't always fit properly...where did you get the A-9735
coil from?

And as for fitting, is this a relay or an action coil? If an action
coil there are coil holders that have slots for the front hole so they
can be adjusted for off-size coils, otherwise I think you can file the
sucker...

John :-#)#

Hi John,
Thanks for your follow up. I did not mean to imply that your chart
should be changed, just pointing out that it's very useful.  Thanks for keeping that posted.

I now realize that adding the height of the coils would be useful
information to add to the chart - especially for substitutions. No problem!

This is a relay coil.  I'm helping someone who sent me an email question about where to get an R20-4 coil.  Searching for R20-4 coil turns up
lots of places selling the A-9735 as a substitute so I assumed this was
just a naming or insignificant resistance difference.

I'll see if he can file it down to fit.  I wanted to check here first to see if there was any experience with this problem.

- Kerry

John :-#)#
--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
#7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

--- Synchronet 3.19a-Win32 NewsLink 1.113

From Newsgroup: rec.games.pinball

The heights are:
R20-4: .985"
A-9735: 1.008"
--- Synchronet 3.19a-Win32 NewsLink 1.113

From Newsgroup: rec.games.pinball

On 2022/11/14 2:02 p.m., P2K wrote:

The heights are:
R20-4: .985"
A-9735: 1.008"

Thanks, added Height of Coil - inches to the list.

John :-#)#
--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
#7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

--- Synchronet 3.19a-Win32 NewsLink 1.113

From Newsgroup: rec.games.pinball

On 11/14/2022 4:02 PM, P2K wrote:

The heights are:
R20-4: .985"
A-9735: 1.008"

Thanks for the height information. I did not see this height difference
in any online sales listings I found.

FYI... I was rechecking today and see that Mayfair Amusement shows an
R20-4 available and doesn't mention that it's a substitute.

- Kerry
--- Synchronet 3.19a-Win32 NewsLink 1.113