Home | Contact Us | FAQ | Search & Site Map | Link to Us
Sign In | Join | Other 45 Sites in Network
Home
Discussion Groups
General
ModelsRailroadsRockets
Radio Controlled
Air ModelsHelicoptersLand ModelsWater Models
ModelGeeks.com
Contact UsLink To UsSearch & Site Map

Model Forum / General / Railroads / March 2005



Tip: Looking for answers? Try searching our database.

Momentary, position-indicating switches?

Thread view: 
Enable EMail Alerts  Start New Thread
Thread rating: 
RWM - 26 Mar 2005 17:00 GMT
Anyone know of a source for momentary, position-indicating toggle or
slide switches with the following logic, to be used to trigger
twin-coil turnout motors and hold position indicating LEDs?

 (ON)-ON-ON-(ON)

 or

 (ON)-ON-OFF-ON-(ON)

In either case, with toggle returning and remaining skewed in the ON
position in the direction of the most recent momentary throw?   In
other words, a sort of mechanical latching.

Thx.
Christopher A. Lee - 26 Mar 2005 17:17 GMT
>Anyone know of a source for momentary, position-indicating toggle or
>slide switches with the following logic, to be used to trigger
[quoted text clipped - 8 lines]
>In either case, with toggle returning and remaining skewed in the ON
>position in the direction of the most recent momentary throw?   In

Hornby make one.

Their switches are shaped to be combined in something akin to a lever
frame, but you could probably fit it into a cutout in the panel.

http://www.hornbyrailways.com/pages/prod_det.aspx?id=1165
RWM - 26 Mar 2005 22:09 GMT
That looks like it fits the bill on the momentary "(ON)" aspect,
remains visually set in one or the other direction, but does not appear
to return and hold an "ON" condition.  Or maybe it just isn't clear
from the Hornby docs.
richard schumacher - 27 Mar 2005 01:33 GMT
> That looks like it fits the bill on the momentary "(ON)" aspect,
> remains visually set in one or the other direction, but does not appear
> to return and hold an "ON" condition.  Or maybe it just isn't clear
> from the Hornby docs.

Why not use a toggle switch and a pushbutton?
RWM - 27 Mar 2005 15:34 GMT
The most elegant solution I've found are rotaries with spring returns
-- if I could find some reasonably priced.  (I'd need 20.)

Cole 3600 series, p/n 3611 or 3608 rotaries would be ideal, for
example.
Steve Magee - 28 Mar 2005 03:05 GMT
> The most elegant solution I've found are rotaries with spring returns
> -- if I could find some reasonably priced.  (I'd need 20.)
>
> Cole 3600 series, p/n 3611 or 3608 rotaries would be ideal, for
> example.

Think outside the square (or rotary as the case may be).

Use a normal 4-position rotary. Call them 1, 2, 3 and 4 - no, the positions,
not the switches! Wire 1 and 4 to your position LEDs, and 2 and 3 to your
switch machines. Treat these ones (2 and 3) as passing contact. Just make
sure you throw the switch all the way, in either direction.

Steve
RWM - 28 Mar 2005 18:48 GMT
If I were the only one operating, perhaps, but given how fragile those
turnout coils can be, that looks like a recipe for disaster...
richard schumacher - 29 Mar 2005 15:36 GMT
Maybe this was answered and I missed it: why not use one SPDT toggle
switch plus one pushbutton, or (if continuous LED indication is desired)
one DPDT toggle plus one pushbutton?  Sure, it seems inelegant, but it
meets the requirements, it's safe, and it's cheap.
David J. Starr - 27 Mar 2005 19:01 GMT
> Anyone know of a source for momentary, position-indicating toggle or
> slide switches with the following logic, to be used to trigger
[quoted text clipped - 11 lines]
>
> Thx.

   A lot of  us  would like such a switch, but I have never seen any at
a price point  suitable  for model railroading.
  The  most straight forward solution uses twincoil machines with
auxilary  contacts to drive  position indicating LEDs or lamps.
Unfortunately the common Atlas snaptrack switch machine lacks the
necessary aux contacts.
  For the Atlas machines I have used one of Peter Thorne's CD circuits
from "Model Railroad Electronics"  Kalmback Publishing MR handbook 37.
The circuit uses  two capacitors, six resistors  and  two SCR's. It will
 drive position indicating LEDs with ease.  I built up several  from
scrap  parts  and they  work well.  Part values are not critical.  The
SCR's handle the heavy current from the capacitors  to the  coils, the
control switch just carries the light SCR trigger current, which  means
low cost switches will last forever.

David Starr
Bill - 27 Mar 2005 22:25 GMT
------------------------------------------------------

Rob Paisley's site might have some useful information:

http://home.cogeco.ca/~rpaisley4/CircuitIndex.html

Another good electronics book is, "Complete Guide to Model Railway
Electronics" by Roger Amos:

http://www.amazon.com/exec/obidos/ASIN/185260591X/qid%3D1021573547/ref%3Dsr%5F11
%5F0%5F1/103-0961217-9639034/billsrailroaempi/102-7028332-4471300


This book is 34% off list price and includes free shipping on orders
over $25.

Bill
Bill's Railroad Empire
N Scale Model Railroad:
http://www.billsrailroad.net
Brief History of N Scale:
http://www.billsrailroad.net/history/n-scale
Model Railroad Bookstore:
http://www.billsrailroad.net/bookstore
Resources--Links to 1,000 sites:
http://www.billsrailroad.net/bills-favorite-links
Rob Paisley - 29 Mar 2005 16:54 GMT
> ------------------------------------------------------
>
> Rob Paisley's site might have some useful information:
>
> http://home.cogeco.ca/~rpaisley4/CircuitIndex.html

 Here is a specific link  for toggle switch control of twin coil
machines from my site.

http://home.cogeco.ca/~rpaisley4/ToggleTwin.html

Rob.
RWM - 30 Mar 2005 17:50 GMT
Thanks, Rob (and other suggesters).  I guess the answer is to do it
electronically.

One further question:  Do you have a rapid LED indicator turn-off
circuit for the Atlas and similar twin-coils with no separate coil
wiring?
Rob Paisley - 31 Mar 2005 02:26 GMT
> Thanks, Rob (and other suggesters).  I guess the answer is to do it
> electronically.
>
> One further question:  Do you have a rapid LED indicator turn-off
> circuit for the Atlas and similar twin-coils with no separate coil
> wiring?

-----------------

 I have added 2 new circuits for Atlas and similar machines.  In all
cases an extra pole on the toggle switch can be used for frog polarity
control.

http://home.cogeco.ca/~rpaisley4/ToggleTwin.html

Rob.

http://home.cogeco.ca/~rpaisley4/CircuitIndex.html
RWM - 31 Mar 2005 02:50 GMT
>  
>
[quoted text clipped - 18 lines]
>http://home.cogeco.ca/~rpaisley4/CircuitIndex.html
>  

Terrific!  Many thanks, Rob.

- Bob
Trainman - 28 Mar 2005 04:59 GMT
> Anyone know of a source for momentary, position-indicating toggle or
> slide switches with the following logic, to be used to trigger
[quoted text clipped - 11 lines]
>
> Thx.

Walthers used to sell a standard Cutler Hammer lever switch that did just
that, they called it the "Toggle Key".

You'd have to peruse electronics catalogs to find it however,  Try looking
under "lever switches" or "Telephone switches".  It's a style of switch that
was used years ago in telephone switchboards.

Don

--
don.dellmann@prodigy.net
http://www.geocities.com/don_dellmann
moderator: WisModelersAid@yahoogroups.com
moderator: MRPics@yahoogroups.com
moderator: vintageHO@yahoogroups.com
co-moderator: SCENERY@Yahoogroups.com
http://groups.yahoo.com/group/MRPics
http://groups.yahoo.com/group/vintageHO
 
Sign In
Join
My Latest Posts
My Monitored Threads
My Blog
My Photo Gallery
My Profile
My Homepage

Start New Thread
Enable EMail Alerts
Rate this Thread



©2008 Advenet LLC   Privacy Policy - Terms of Use
This website includes both content owned or controlled by Advenet as well as content owned or controlled by third parties.