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Pennsy RF-16 Baldwin Diesels

Started by Cobrabob8, September 06, 2012, 08:11:46 PM

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DominicMazoch

Er, KCS and MKT did not have them either!

Joe Satnik

#16
Dear All,

NOTE:  SEE NEXT POST FOR CORRECTION

A crude Bell Button:  

6 amp or larger diode (example:  Radio Shack 276-1661 ) in series with one of the 2 wires between the transformer and tracks.

Jumper (short) across the diode for normal operation, temporarily remove the short (un-clip one end of the jumper) to activate the bell.

If you get the horn instead of the bell,  turn the diode around (in the other direction).


Transformer Term. 1----------------------------->l-----------------center rail          (  -->l-- = diode)
                                                          l                  l
                                                          l--short------l

Transformer Term. 2-------------------------------------------------outer rails

The reason I call it crude is because it will slow your train down as you activate it.

Not slowing down takes a little more thought and complexity in the design.    

Once you get it working, buy a 6 Amp or better momentary-off NC (= Normally Closed) SPST push button switch to replace the jumper.  Example:

http://www.ebay.com/itm/2pcs-BLACK-Head-MINI-Push-Button-Momentary-NC-SPST-ON-OFF-Switch-10mm-/160894894756?pt=LH_DefaultDomain_0&hash=item25761542a4


Hope this helps.

Joe Satnik
If your loco is too heavy to lift, you'd better be able to ride in, on or behind it.

Joe Satnik

Dear All,

A few more thoughts.

The reason the bell button from Brand L fails is because it's not made to handle a dead short at the tracks, which happens all too often. 

(A derailed wheel touches both the middle and outside rail.)

Rough calculation with an old ZW:

275 Watts/20 Volts =~ 14 Amps, for at least as long as it takes to trip the ZW's internal circuit breaker. 

The switch and diode in my crude bell button would be safer at 20 amps, not 6 Amps, so I'll look for more robust components.

Hope this helps. 

Sincerely,

Joe Satnik   
If your loco is too heavy to lift, you'd better be able to ride in, on or behind it.

Joe Satnik

#18
Dear All,

Switches:

The Cherry E13 series 15 amp switches on e-bay would work, and are reasonably priced.  

E-bay search word: cherry 15a  

Either a 3 terminal (wired NC - COM,  Normally Open "NO" terminal not used),

or the SPNC (Single Pole Normally Closed "NC")  2 terminal.  

Both types are momentary.

One of the auctions is for a lot of 10.

Any of the auctions with the dollar bill in the picture would work.

Diodes:  

Example:

E-bay search word: diode 15a 45v

The two outer terminals of the 3 pin tab diodes would have to be connected to one another. 

The cylindrical Schottky diodes (2 leads) would be simpler. 

Hope this helps.

Sincerely,

Joe Satnik

Edit:  Added diode info.


If your loco is too heavy to lift, you'd better be able to ride in, on or behind it.

671

Hi Joe,
         I think I have the answer to what I am looking for in a whistle / bell controller.

Follow my thought...
   1.   A double pole double throw switch of sufficient amperage. ( 20 amps )
                                           1     3     5     
        Terminals on switch 
                                           2     4     6

Wiring...  Transformer output to terminals 1 & 2
             Track input to terminals              3 & 4
             Cross wire terminal #1 to terminal #6
             Cross wire terminal #2 to terminal # 5
    This type of setup will allow you to use the existing whistle switch on your transformer ( I.E. ZW ) as a whistle/horn blower in one position and a bell ringer in the other position. By toggling the double pole double throw switch to it's other position, will allow the DC carrier to be reversed. This will then ring the bell.

                          What do you think?...671

Joe Satnik

Dear 671,

It could work. 

One concern would be the "glitch" or "voltage dropout" that would occur as the switch contacts "break" then "make" to the other polarity.

Will that dropout be long enough to put the electronic reversing unit into its next step, which is neutral, stopping your moving train?

Even if the loco stays in forward, will it stumble enough to be visually distracting?

Another concern would be the transformer's inductive kickback from suddenly being disconnected from its load. 

That's how an old Kettering (points) ignition system works in a car.

How about two 43 volt TVS circuit protectors, one across the lines on both sides of the switch?

1.5KE43CA from Digi-Key (or other sources) has a reasonable price and would do the job.   

It's a nice experiment to try if you're not worried about the cost of the switch and the 2 TVS's. 

Transformer terminal 1----------------------- ------dpdt--------------------Track center rail
                                                      l                 \   /           l
                                                   TVS                 X          TVS
                                                      l                 /   \           l
Transformer terminal 2-----------------------------switch-------------------Track outer rails

Let us know how it turns out.

Hope this helps.

Sincerely,

Joe Satnik
If your loco is too heavy to lift, you'd better be able to ride in, on or behind it.

671

Hi Joe,

         Thanks for the quick response. I think due to the fact that the Williams loco's have a capacitor in their electronic E-unit that momentarily holds the existing E-unit's setting when they cross a switch or rail crossing track, I should be OK.

          I will try to do a test model this coming weekend. I will run Williams and Postwar Lionel as a test.

          I will let you know the outcome.

                                  671