Lionel 1122 switch modification

Yes.

Yes, unless you search for & perform this modification which eliminates the buzzing.

Rob is right, the only sure for the buzzing is to not have current constantly applied to the coil when you're parked on them.  Constant voltage feed won't accomplish that.

IIRC, the simplest way to stop the buzzing would be to disconnect the two ground wires, one from each end of the solenoid, to the outside rails (the rails that have the fiber pins in them.)  Of course that would make them no-longer non-derailing. 

Just thinking out loud, if you wanted to activate the non-derailing feature you could install a Double Pole-Single Throw ON/OFF toggle switch in the circuit between the solenoid and the rails.  Then you could turn the non-derailing feature on and off as needed.

OK - I think i've got this ..... modify  the switches to run on constant voltage. Add a toggle switch to cut the power when I park a train on top of the switch. Turn it back on when I want it to be non-derailing.   Does that sound right?  That's option one.

Is there a second option that involves adding capacitors? Might there be a diagram available?

Spud

The thread John suggested discusses the use of capacitors and DC to power the solenoid instead of AC.  Since this is a more sophisticated method it would prevent the solenoid from any buzzing.   I read through it a few times and it doesn't look too difficult. 

I think the most relevant post was this one "I ended up with the original setup......power from ZW to diode (1n4001) to 100W resistor to 4700uF capacitor . The anode end of the capacitor also has the jumper wire from the switch attached there and the other end is attached to the ground terminal on the switch." 

Since the topic is less than a month old you could probably ask the guys in that thread to help explain the conversion to you.

I would think that if you powered the switches by D.C. instead of AC, there might be no  more buzzing, but if you parked cars on the switch, D.C. power would be constantly applied and possibly burn out the solenoids. I'm sure they would heat up pretty good even if they didn't burn out.

The whole point of the capacitive coupling is to NOT continuously send current through the coils.  AC or DC, continuous current will smoke the coils.

Read through the modification.

The DC is just for charging the capacitor, the capacitor throws the switch.  Your goal is to shut off/minimize current to the solenoids when a train is parked on the control rails.  The modification is brilliantly simple and effective.

Bob (lionelsoni) is the person that helped my years ago, after which I collaborated with him and submitted an article to OGR on it (the one that I constantly refer to in these threads).  Bob didn't want to write the article so I did, giving him complete credit.  I included maybe a dozen pictures too.

I've sent that article to many people including the person that started the thread (rogerNY) that is linked to above.  He and I have exchanged a few emails on it since.

Bob has recently offered an alternative to the resistor - using a #53 bulb (I don't know what that is, but it was the one recommended).

If you want the article with pictures and a schematic shoot me an email and I will send it to you.

Again, I want to stress that this is not my creativity at work.  It's ALL Bob Nelson's creativity and knowledge.

- walt

Thanks for the article Walt.

Thanks for the PDF! That is exactly the project I have been considering and you have saved me from re-inventing the wheel!

Gosh, I guess I was too fast, I should have waited for your version!

Thanks gunrunnerjohn. 

I haven't re-read my writeup in several years and forgot that I had an edited version.  I'll have to check and make sure that the document that I have been sending is the newer, edited version.

I looked at your PDF and some of the pictures, at least on the monitor here at the library, makes the detail hard to see.  I'll check the images that I sent to you and see if they too are hard to view detail in.  The images that I sent are digital retakes of film prints so I expect some lose of quality.  If my images are not clear enough I will try to improve them by taking re-takes to try to up the quality.

- walt