Whissle / Bell schematics

[Cacau]

Hi,

I'm trying to implement  a Whissle and Bell buttons on a custom power supply I'm building. I realise that lionel makes them, but , as I said, I'm building a custom panel/ control borad/ power supply, that will control a lot of thing. 

 

I know that the whissle and bell implies using some form on  DC currrent on top of AC, but I would  prefer to just look at simple schematics to decide how to do it in my case. 

 

I found an older forum post with an schematic, but unfortunately it was so small I could not see it.

 

Thanks.! 

 

[Cacau]

ok, I guess nobody has schematics. Anybody can give me any clue where can I find information to build my own bell/whissle controllers? Any help would be apreciated. Thanks.

[anjdevil2]

for schematics, I'd try Olsens toy trains.  Other than that, I'd look for a book called Modern toy train repair.  I suggest you find one and peek inside to be sure it's the right book.

[Cacau]

thanks!

 

However, I had already looked at olsen's and did find anything about teh independent bell and whissle controllers. I found something about it on the schematics of the 1033 transformer, but that is diferent than the independent whisstle controller that was installed between the regular transformer and the track.

 

I do know that the controller is supposed to provide DC to activate the whissle, but I don't think the schematics involves a simple diode....  

 

There is an old thread that goes into a lot of detail. it even gives a parts list. The only (BIG) problem is that the picture showing the schematics is very small, we cannot see it.

 

Thanks, 

[Cacau]

This is the old thread I talked about:

http://cs.trains.com/forums/428938/ShowPost.aspx 

[dsmith]

Here's one simple way of having a whistle/bell controller.  The circuit uses a bridge rectifier and a double pole switch.  I would use at least a 3 amp 50 volt bridge rectifier.  The switch I use is a double pole double throw normally closed spring loaded toggle switch that is rated for at least 3 amps.  If you can find a double pole normally closed push button switch, that would be ideal, but haven't been able to find any.

Here's how the circuit works.  With the switch normally closed, the bridge rectifier is bypassed and AC is applied to the track as normal.  If the switch is opened, the bridge rectifier is now in the circuit and full wave DC is applied to the track.  Engines with a whistle will work if the DC is applied in one direction and the bell will sound if the track wires are reversed.  If you want to do both, just build 2 circuits and hook the track wires up opposite.

If you need any of this clarified, just ask.

[Cacau]

Dsmith,

thank you very much! this is exactly what I needed it!

 

Question, for the bell (versus the whistle) , I just invert the polarity going to the track, right? In other words, if for the whistle to work, the "+"  sign of the bridge goes to the center rail and the "-" goes to the outside rails, then, to activate the bell, I have to put the "+" on the outside rails and the "-" on the center rail, right? 

 

Thank you very much! 

 

[dsmith]

Cacao,

Yes, you are right.

Here is the momentary toggle switch I used, it's from All Electronics.

http://www.allelectronics.com/make-a-store/item/STS-115/DPDT-ON-ON-MOMENTARY-TOGGLE-SWITCH/1.html

 

[lionelsoni]

David, I don't see how that could work.  With the switch closed, two of the rectifiers are connected across the transformer's terminals.

[dsmith]

Well lionelsoni, you're right.  I drew this diagram from memory and sure enough, it won't work.  So don't believe everything you read on the internet.  I'll have to open up my control panel and see what I did and redraw the schematic.

My diagram above has been corrected.

David 

[BobbyDing]

Here's a modified Lionel schematic for my modified 1033's (below). The diode arrays at the bottom is where you might get some ideas from. The reason for this was that all my locos would take off or slow down whenever I blew the whistle via the 1033(s). It was real bad with the K-line Porter. The darn thing would launch down the track!! After weeks of tinkering I came up with this, and it works great for me. The extra 5 volt windings are now always in service to compensate for the large voltage drop of so many diodes. Thru experimenting, I HAD to use this many diodes for ALL my loco whistles to work. Fewer diodes worked for the electronic whistles, but the post war whistles required this many diodes (though admittadly I don't run the PW too often). So what's the benefit?  All my locos now maintain the same speed, and the lights stay at the same brightness when the whistle or bell is triggered. No more sudden drag races. The 1033 now triggers the bell too. I used 6 amp 200 volt diodes (mouser). They are mounted in the 1033 case, so they look like standard 1033's (little picture at left).

This diode array could be used externally with a couple of momentary toggle switches taking the place of the 1033's lever. These diodes will drop the track voltage however by about 3 volts for normal running. So a few extra volts from the transformer would be required to keep things even. You may be able to get away with fewer diodes too. Be aware that the diodes DO get hot during use.

Hope this helps....

Bobby

[Cacau]

David,

I apreciate if you could do that (check your own wiring), as I prefer your approach than put all of those 6 diodes. In my case, I have a custom transformer and that would drop the voltage too much.

My guess is that your circuit must have some kind of relay which is normally open ,which when trown,  would then connect the rectifer somehow.

 

Cacau 

 

[lionelsoni]

An alternative to using individual diodes (actually 14, not 6) is bridge-rectifier modules, which can give you the equivalent of two diodes in series.  Use the + as the cathode and - as the anode, with the ~ terminals connected together as the center tap.

[railfancwb]

Question, for the bell (versus the whistle) , I just invert the polarity going to the track, right? In other words, if for the whistle to work, the "+"  sign of the bridge goes to the center rail and the "-" goes to the outside rails, then, to activate the bell, I have to put the "+" on the outside rails and the "-" on the center rail, right? 

I thought that only half wave DC would be fed to the track rather than full wave -- plus to center rail for one function, minus to center rail for the other, with AC to the running rails in either case.  Am I wrong?  The reason I thought that is that numerous warnings on modern locomotives say not to hook them up to DC, that it can do bad things to their electronics.

[dsmith]

I have looked at the circuit I use and here is the corrected diagram.  Occasionally, if the switch is toggled or released slowly, there is a fraction of a second  where the track receives no power and the engine will cycle to neutral.  The second circuit eliminates the cycling problem by providing 1/2 wave DC to the track during that fraction of a second that the switch is thrown.  I might change mine to the Lionel circuit sometime if the cycling problem becomes too annoying. 

Both circuits provide full wave DC to activate the whistle/bell.  I don't know of any problems with modern engines having problems with DC, perhaps someone in the know could enlighten us if there are problems.  I have 2 modern engines with electronic circuit boards and haven't had any problems. 

 I also have taken appart one of the simple Lionel whistle/bell buttons.  Here is the Lionel circuit using a DPDT switch and 4 diodes. 

[lionelsoni]

Mrb, although there are three rails, the outside rails are connected together; so there are only two connections to the locomotive and therefore only a single circuit and a single voltage at any one time.  That voltage is AC for normal running, with no DC component.  To blow the whistle, there must be at least a small DC component; and there are various ways to add that component, including the Lionel transformer's method of a 5-volt boost and a single diode-resistor parallel pair in series, diode strings with switchable taps, a dry cell in series, and switching in a bridge rectifier.

For an older locomotive with a whistle-horn relay, the polarity of the added DC doesn't matter.  For newer locomotives with electronics, the polarity is often used to select between whistle or horn on the one hand and bell on the other.  The sense of that polarity is that a center rail more positive than the outside rails blows the whistle or horn, a center rail more negative that the outside rails rings the bell.

A modern locomotive will see the necessary DC just as an old one will.  Whether a lot of DC, more than needed to blow the whistle, will harm the locomotive is another matter.  My experience and intuition is that it won't and that manufacturers who say that it will are either trying too hard to protect themselves from liability or want to avoid complaints that the whistle either blows all the time or doesn't blow at all.

David, that looks better!  Anyone who uses those circuits however should be aware that any common connection from a multiple-output transformer will not exist downstream of the whistle circuit when the whistle is blown.  This means that the outside rails must be gapped between blocks, that any accessories using a control rail need special consideration for their power supplies, and that running between blocks powered by different transformer outputs is an even worse idea than I usually preach that it is.