I am considering this in lieu of mending plates for a lift out bridge section. Thought is that the phono jacks would make it easy to remove and reinsert the section, would help with alignment and would be cleaner than a quick release male/female type of connector. Question I have is (for all you electronic gurus out there) is if the bridge is the only thing that the connectors will power (layout will be powered from each side independently) will these connectors work? Or scrap this idea and go with the mending plates? Considering resistence and load to be carried. I am using a prodigy advance 2 with NO boosters.
Archipapa,
It could very well wind up being the weakest link in your layout. Consider something more robust, do it now rather than later. You won’t regret it.
Have Fun!
Frank
I recently installed a plug and jack for a liftoff section in my layout. It’s scenery-only, so the power was just for structure lighting and streetlamps, but the principle is the same. I went to an electronics place and got a two-wire automotive trailer connection for a few dollars. This is a very robust connector. The first time I plugged it in, I needed pliers to pull it apart, but it seems to work great just half pushed in now.
One thing you should seriously consider is wiring not just the bridge, but also the approach tracks for several feet on either side of the bridge. This will stop a train before disaster happens. And yes, disaster does happen. I would wire in some signals, too, to let you know the status of the bridge connection, and because signals are something everyone likes.
I use a phone plug for my turntable pivot and it works OK. However, for a lift out section I would use another type of connector. One with two dedicated pins that don’t wipe past each other when being inserted or removed like the phone plug.
If you use two, or four (necessary for alignment) and only feed one rail through each, they should work. However, the plastic sleeve on the plug isn’t designed to take much stress.
I use stereo jacks as switch keys and as block tickets in staff-and-ticket track occupancy control. These are the 1/4 inch size, not those wimpy miniplugs.
Chuck (Modeling Central Japan in September, 1964)
In my previous layout design, there was to be a liftout section. I went with a different design, but in that design, I ran the power to the liftout section. The approaches from either end were insulated, so they only had power when the liftout section was in place.
Like Marlon, I ran power to the liftout, then from it to the isolated track sections on either side. I used a 5-conductor plug from Radio Shack, with the fifth prong merely to ensure proper orientation of the others.
Wayne
When I built my most recent turntable, I found a new 1/4" phono plug at Radio Shack that was more robust than the standard ones. Worked great for that. Worth checking out if your application really would work better with a plug and socket arrangement.
EDIT: Found a pic of the phat jack – or at least part of it sticking out of the underside of this turntable:
There are two different sorts of things being talked about here. The device used for the turnbtable pivot is a Phone Plug. A Phono plug is like RCA jacks on audio and video cables.
Problem with a phone jack for something that might be plugged and unplugged while the layout is in operation is that they short when plugged in. You have to be very careful which connections are used - a stereo phone plug has 2 bands, making 3 sections, the tip, the middle ring, and the top ring. If you use the tip and upper ring, there won;t be a momentary short. RCA plugs, phono plugs, do not short. They are robust enough to carry the power for a lift out section.
Both have a flaw in that they offer 2 conductors - that means simply unplugging the wire will have no way to disable power on the approach to the bridge. With a 4 wire connector like the trailer plug you can feed power for a train length on either side of the bridge through the same connector so that when it is unplugged, both the bridge and the approaches have no power. Using leaf swithes or some part of the latch as the contact has a distinct advantage over using any sort of plug-in cable - you can never start to raise the bridge or remove the liftout only to have it jerked back and dropped because you forgot to unplug the wire.
–Randy
In using a PHONE plug, the barrel is GROUND and the tip is pwered. There should be no problem pushing it in or pulling it out. LION builds with the left rail GROUND and the right rail either + or - power depending on direction of travel (+=Forward).
For bridges and etc… LION has none, but him has automated layout, with no throttles, no reversing switches and no train controls at all. LION can walk all around the room while the trains are running. In case of problem, LION has Power-Cut-Off switches around the layout. These are NC pushbuttons, so pressing the button breaks the protection circuit and shuts everything off. If LION had a bridge-gate (or a fat [tasty] governor) him would place that bridge in the protection circuit : Nothing runs anywhere when bridge-gate is in session.
That is what LION would do.
Is what LION did do… sans the plump executive and his bridge-gate.
ROAR
The problem I see w/ using these as a means to locate the liftout, is that any benchwork movement due to enviormental conditions (extreme humidity or serious drying of the wood), can cause misalignment/ side forces on the “pins”. I don’t know the conditions of your layout space or the actual construction, but may want to take this into consideration first. There are many other methods of alignment that can work even w/ movement. If the liftout can be stored in a close proximity (brackets etc) a longer length of wire and a connector can be used. Flat plate contacts or microswitches can take the place of the “jacks” to kill power to the approach.
Since you want to both locate and power a lift-out section using some type of plug/jack combination, what about using standard A/C electric outlets and grounded plugs. The outlets can easily be secured to the layout benchwork using standard construction boxes. The grounded plugs will require a little engineering to permanently anchor them to the lift-out section but that shouldn’t be too difficult. The plug type used to repair the ends of damaged power cords usually incorporates some means of separating the front and rear of the plug to insert the wires. This feature could be used to “sandwich” a mounting plate between the two halves of the repair plug, thereby locking it in place. The ground prong would ensure that the wiring polarity could not be reversed. These outlets/plugs should prove plenty robust, too.
Alternately, you could use the outlet and plug (on a short length of cord) to connect/disconnect power to the lift-out and approach sections while using a less complicated method of locating the lift-out section. Again, the outlet/plug combination should prove plenty robust for the task and the ground prong would ensure that the wiring polarity could not be reveresed. Just a thought.