Making a switch to activate bell

[jac]

  I recently purchased a Williams O27 Hudson item no. 40101. I am currently running the train with an old Lionel 275 watt ZW transformer with only the whistle button.Several people have told me I can make a switch,I believe using a double pole switch.I am aware Lionel makes a sound switch (6-5906),however I would prefer to build one using 16 gage wire instead of the thinner wire Lionel uses.When running my post war Lionel Engines with the thinner wire the engine slows down considerably when activating the whistle.This doesn't happen with the 16 gage wire.Any help would be appreciated.Thanks                                                                                                                                               jac

[Joe Satnik]

Dear jac,

I, too, am not a fan of the wimpy 5906 bell button, but its thinner wire is only a small part of the slow down problem. 

Also, I don't think the bell button was meant to operate the old air whistles.   

The post-war Lionel steam locos have a motorized blower for an air whistle in the tender, which puts a significant extra load on the transformer and track wiring.

On top of this, the means to signal or activate the whistle is to block part of the AC power wave. 

So, a bigger load and less transformer power causes the loco to slow down.

Lionel compensates for the slow down by adding a 5 Volt AC boost winding to the whistle activation circuitry.

The newer Williams/WBB steam locos have a sound chip and speaker, (True Blast II) which take significantly less power to operate. 

The power wave is still partially blocked, though, to activate the sound chip, so you can expect some slow down, but not as much.     

The Lionel bell button has no provision for a boost winding, and is light duty (small current loads) only. 

(Avoid long heavy consists, gradients, and lit passenger cars.)

Do a search Bachmann board search on "zollo" or "eichenberg" or "bell button" for discussion and diagrams of heavy duty bell buttons.   

Hope this helps.

Sincerely,

Joe Satnik

[the nitro man]

i've noticed with my zw, i can't push the horn bottun all the way forward & get the newer stuff to work. it runs my postwar stuff great, but anything with a circuit board i have to push it only about half way. i guess it because the newer stuff uses so much less current?

[Joe Satnik]

Dear Nitro and All,

ZW and other post-war transformers use a 2 step whistle/horn switch.

http://pictures.olsenstoy.com/cd/transfmr/psvw1.pdf

First step (lever half way) adds 5V AC to the AC track voltage (8 to 20 volts AC) and rectifies the power wave, which results in a significant DC voltage offset, which kicks in the tender's air whistle DC relay.

Second step (lever all the way) bypasses the rectifier with a 1.5 Ohm resistor in parallel, restoring much of the boosted AC (13-25 Volts AC) waveform, but allowing enough of the rectifier's DC through to "hold" the whistle relay in the "active" position.  The boosted AC now spins up the whistle's motor.    

One interesting test of your "less current" theory would be to put an old air whistle tender on the track with a newer diesel.  Perhaps the diesel horn would work at full lever with the added electrical load.   (More current pulled through the rectifier causing more DC offset.)

I think the 8V AC minimum track voltage is causing way too many headaches for Williams/WBB owners, enough to recommend the ZW not be used without voltage reduction mods to the Williams/WBB locos.

This modification is very simple for 2 motor locos,  tougher for single motor locos.  

Hope this helps.

Sincerely,

Joe Satnik

Edit:  added "modification"

[jac]

Joe,
Thanks for all the information you've provided. I found your article from September 27, 2010 on how to make a heavy duty bell button. I went to Radio Shack to purchase the parts needed to build the switch. However, they don't have the 276-1661 diodes listed in their system anymore. They did have a 276-1653 diode. I also called Digi-Key and they have a 6amp 50 volt diode part number 6AO5-TP. Would either of these work?

Radio Shack did carry the 3 amp 275-1549 switch. They didn't have a 275-016 switch however, they did have a 275-0016 spdt sub mini lever switch rated at 5 amps at 125/250 vac. Digi-Key had a spst normally opened switch rated at 5 amp, 120 volt AC part number GH1358-ND. Would either of these 5 amps work because I prefer to go with the heavier switch.

Any feed back on which diodes or switches will work will be greatly appreciated.

Thanks

[the nitro man]

i just bought 2 packs of 276-1661 diodes no more than 3-4 days ago from radio shack. they do have them online. & there is 5-6 packs on ebay right now. just put in the part number on the search.

[Joe Satnik]

Dear jac,

Any diode 6 amp or greater, 30 Volts reverse or greater will work. 

Since rectifier diodes only seem to come in reverse voltages of 50 V or greater,  any 6 amp or greater diode will do.

Radio Shack  doesn't seem to have a switch on their website that will do for this application.   

There always seems to be at least one spec that is lacking. 

What is needed is a momentary SPST N.C. (normally closed) push button switch, 6 Amps or greater.   This provides the action we're looking for: Push(off), Release(on).   

Its visible parts should look nicer than ugly, and fit in the space you want to mount it.

An alternative switch configuration is a 6 Amp or greater momentary SPDT, which has 3 terminals: Common, N.C., and N.O. (normally open).   

If the Common and N.C. terminals are used (N.O. terminal ignored, not hooked to anything), it will function as the SPST described above, namely: Push(off), Release(on).  It must not have a "center off" position. 

Again, no go for an SPDT at Radio Shack.  They always seems to be lacking in at least one spec.....

I have been shopping on e-bay for a usable switch at a reasonable delivered cost. 

I stumbled on this one using the keywords: "momentary push button".

It's a little big, but it has a reasonable "buy it now" price plus shipping:

http://cgi.ebay.com/Micro-Switch-Cherry-E13-momentary-pushbutton-/360204908054?pt=LH_DefaultDomain_0&hash=item53dde2b616

Hope this helps. 

Sincerely,

Joe Satnik