Help! Manual operation of 148 dwarf signals

[Anonymous]

Hi, what kind of switches do I need to manualy operate 148 dwarf signals and where can I get them? I am looking for two. I think the Postwar ones came with a 390C. Thanks for any help.[8D]

[jkerklo]

The postwar 148 Dwarf Signal came with a 148-100 manual, DPDT switch. The switch allowed an operator to connect the switch to the track center rail and the signal lights on the 148. The switch could be thrown to turn power on in a siding or other part of the track and the signal would change lights to show the powering condition of the track siding.

The 148-100 may be hard to find, but check parts suppliers.

Any DPDT (Double Position, Double Throw) switch will work. Places like
www.Jameco.com or www.Mouser.com have them in great variety. They are almost as common as dirt. You will need one with a 10 amp rating if you are going to use it to switch center-rail track power.

Connect track power to the "C" (Common) terminal of one set of contacts and the track center-rail to one of the other terminals of the contact set.

Connect one side of your accessory voltage (12 volts) to the common on the track signal.
Connect the terminal for the red bulb to the terminal opposite the one you connected track center-rail to ON THE OTHER SET OF SWITCH CONTACTS. Connect the green light to the opposite switch terminal. Connect the other terminal of your accessory transformer to the common (usually center) position of the switch contacts being used for the signal lights.

When the switch is in one direction, the track center-rail will be off and the 148 will show green. With the switch in the other direction, the track center-rail will be on and the 148 will show red.

The 148 signal is really the same as a 153. It can be used with a switch or connected to operate automatically as a train moves through a block.

You can use just isolated outside rails or, of course, Three-Rail Innovations' Universal Trackside Accessory Controller.

See http://www.three-rail.com/TA153.HTM for how.

The UTAC will operate four block signals, and anything else.

Go to "SUPPLIES" on the www.Three-Rail.com web site for URLs for electrical suppliers for the switch.


John Kerklo
TCA 94-39455
www.Three-Rail.com