Toy train operating and collecting

The diesel horn on my SantaFe 2343 does not work.  The battery is fine.  I checked resistance through the horn to the horn case with the horn removed from the engine and the circuit is open. I did notice another insulated lug on the bottom of the horn with nothing attached to it.  Is that lug supposed to be the ground or does the case provide the ground? 

The horn is a sealed unit but there are tabs on the top of the horn that holds the top on.  I might be able to get to the horn innards by removing the top.  Has anyone ever repaired one of these horns and will removing the top of the horn gain access to the electrical components?  There are a lot of tight fitting tabs on the top lid, so I don't want to risk damaging the horn if I still cannot get to the horn electrical components.

There is also a screw on the bottom of the horn that I assume adjusts the sound of the horn.  Is that assumption correct?

Earl

The horn is essentially a buzzer.  It has a coil that attracts the diaphragm and an electrical contact that disconnects the coil when the diaphragm moves closer to the coil.  The screw adjusts the point where the contact disconnects.  It is possible that yours needs adjustment so that the contact is closed when the horn is off, which is proper.

However, be careful in adjusting it.  If the problem is something other than the adjustment, you could get it so far out of adjustment that you could damage the innards and ruin it.  I recommend marking the adjustment screw so that you can always return it to its present position.  Then adjust back and forth from that position by an amount that you gradually increase, until it either begins to work or you get the feeling that it couldn't possibly be mis-adjusted by the amount that you are turning the screw.

If you can't fix it that way, there's not much to be lost by taking it apart.  But I wouldn't have much hope of getting it back together.  Been there, done that. 

Before you take your horn apart, there are a couple of things you can try.

First, try taking a pair of wires connected to a toy train transformer, set to about 20 volts (A,C. is fine). hold one wire against the case, and brush the other wire against the horn relay terminal that is connected to the horn. Often the high voltage gets things going.

If that doesnot work, use aligator clips to attach the wires, and take a blunt object (the end of a toy train "log" works well) and sharply strike the diaphram that is visible in the opening of the horn.

If neither of those actions fix the horn, you may be able to dismantle the horn and fix it. I have fixed several horns. The problem often seems to be corrosion of the area where the horn's coil is grounded.

In other words; 'The Ole' Repair Hammer!'

Either way, it solves the problem!

Ralph

Thank you for all of your suggestions.  I tried all of them (screw adjustment, 20 VAC shock, and log tap) and was unsuccessful in getting the horn to work.  I was also unable to unbend any of the tabs to remove the top of the horn.  I don't know what the tabs are made of but they are tough.  I lost, the horn won.

Earl

Earl,

I'm, sorry for the hammer joke, but it seemed funny at the time, due to seeing my father, who built T.V.'s, radios and most anything, jokingly pick-up a hammer if an electrical appliance went askew.  He also had a hammer with his electronic test meters, tools-(instruments), a mirror, parts and other assorted needs.

Remember, on a T.V.,when everything stops working, check the '5U4G' vacuum tube, that was mostly the problem.  Now, circuit boards dominate. 

How about, Radio Shack 'Control/Contact Cleaner & Lubricant, it' Non-Flammable to be used in and on eleectro-mechanical devices, reduces wear, safe on MOST plastics.

WARNING: Contents under pressure and Harmful if coming in contact to skin, eyes and inhaling, use in ventilated areas, wear protective clothing and eye cover.

Ralph      

Train-O:

I'm, sorry for the hammer joke, but it seemed funny at the time, due to seeing my father, who built T.V.'s, radios and most anything, jokingly pick-up a hammer if an electrical appliance went askew.  He also had a hammer with his electronic test meters, tools-(instruments), a mirror, parts and other assorted needs.

The "hammer" trick often works when the failure is due to bad contact between the contacts inside the horn. The diaphram acutally acts as a contact inside the horn. Since the tricks I suggested did not work, I would guess that he has the issue with the wire loosing contact. Now that you have the horn apart, see if you can locate the ends of the wire coil. one end should be soldered to a spot on the frame, the other to the vibrator contact. I end that is soldered to the frame is probably no longer making contact. I suspect that the manufacturer used acid core solder for that joint, and over time, the joint corrodes away. I have been able to rig a new connection point. Getting the cover back on, and all those fingers crimped is the final task.

cwburfle,

I know, Earl knows of this remedy and is aware of my joking. 

I agree with you, because I've witnessed and done so.

Of couse, a very gentle tap, at times, does help and hopefully there's no battery leakage, which damaged and caused the horn unit to be inoperable.

My fancy, expensive, new, TMCC diesel engine needed a little, gentile tap and the sound unit started working, as designed.

Thank You,

Ralph

Unfortunately, I could not straighten any of the tabs so I cannot get the horn apart.  The tabs were too hard for me to bend using a screwdriver to pry them outward.

The horn itself looks brand new, but there is some rust or corrosion around the hole where the wire from the horn relay goes into the body of the horn.  There is another electrical contact on the bottom of the horn that is electrically isolated from the body of the horn.  There is nothing externally attached to the contact.  What is the purpose of that contact? 

Thank You...

Earl

Earl,

That contact on the bottom of the horn is the volume control set screw which Bob Nelson referred to.

When your turn it either clockwise, or counter-clockwise, with a minimum amount of electrical current, about 1.5 volts, you should hear the horn sounding.

The horn takes one 'D' size drycell battery, about 1.5 volts, so be careful with the correct amount of juice.  I believe the horn is made to withstand a greater voltage, than 1.5 volts, but don't risk it.

Good Luck,

Ralph

Earl,

         Ground that lug to the loco frame and see if that helps. Early 2343s use the same horn as the 2333, and the horn is mounted by means of a rubber grommet and shoulder screw. That grommet is the reason the lug needs to be gounded to the loco frame to complete the circuit.

If this doesn't help, try heating the tabs with a soldering iron to help them bend easier.

 Ralph,

There is an electrical contact in addition to the adjusting screw on the bottom of the horn.

Jim,

I have tried grounding the lug and that did not work.  The lug is electrically insullated from the housing so I doubt if it was intended to be grounded.  I suspect the lug is used for something internal to the horn.

Earl

Earl,

        If you can't get the horn to work, excellent repro horns are availabe. They are made by Delta Alarm, which is the same company that supplied the originals to Lionel in the postwar years.

EIS2:

I have tried grounding the lug and that did not work.  The lug is electrically insullated from the housing so I doubt if it was intended to be grounded.  I suspect the lug is used for something internal to the horn.

The lug insulated because it is used to mount part of the contact assembly.

EIS2:

 The diesel horn on my SantaFe 2343 does not work...

If all else has failed, simply purchase a new one.