I have some easy-peasy lights for my passenger cars and they work great. I decided to install a light in one of my RPOs using an N battery, a magnetic reed switch and a 1.5v bulb. I built a simple circuit but cannot get the reed switch to stay closed. I tried a couple and every time I remove the magnet, the switch goes off. One I even put in an easy-peasy light to test and it stayed on after passing the magnet over it. What is the trick to making the circuit work. Does the easy-peasy have a biasing magnet built into the circuit?
Mark beat me to it. I have seen latching reed relays, but that was 30-plus years ago. You do not have one by your description...sorry.
These are supposed to be latching reed switches. I did some more fiddling and I'm able to get them to stay closed with an LED circuit, but not with an incandescent bulb. I ended up shortening an easy-peasy circuit board to fit the RPO, I cut about an inch out of the end and re-soldered the leads...works. Just bummed I couldn't get the incandescent bulb to work. I swapped a couple in the easy peasy circuit and they all latched as designed with a pass of the magnetic wand. Just wouldn't do it with the peanut bulb, it might be due to the current flow.....not sure.
The lighting units that turn on / turn off with a magnet have a circuit that does the latching and un-latching. What I’ve done with many of my FREDs is to use a very small slide switch. It is black so blends in real well on the bottom of one of my auto racks, and on the bottom of a trailer on a flat car. I also have one on an Atlas covered hopper that is hidden because it’s between two of the bays. I use a skewer to turn this on or off. I would think on the bottom of an RPO car something like that would blend in well. Brad Myers Peninsula Ntrak / AsiaNrail My Blogs: http://www.n-scale-dcc.blogspot.com/ http://www.palisadecanyonrr.blogspot.com/ http://tokyo-in-nscale.blogspot.com/
When I used to use 1.5v PFM micro-lites for my cabooses (with an AAA battery) I replaced the caboose smokejack with a piece of "t" shaped brass .033 rod, soldered, and made a homemade push-switch all the way through the car to the bottom, so that you simply pushed down on the smokejack to complete the circuit. Worked well. All that stuff has been replaced with Richmond Controls circuits now. For a while I had my entire passenger train lit that way with AAA batteries in the baggage car and a pullman and wires between cars. The 'switch' was a tiny wire on the side of the baggage car that fit up into a slot/latch on the side skirting, looked like a retaining valve handle. If you knew where it was you could just put your thumb on it and turn it on. The battery weight was pretty heavy (and I had steep grades) and those PFM bulbs ate batteries fast, but it worked. The real bear was changing batteries in the two battery cars when everything was wired together.....not my best idea. All easy-peasy lights now. I had to cut one in half to make my dome work and jumper around the circuits. Latching reed switch? Really? I know the circuit itself latches, but the reed switch itself? I've experimented a lot with tiny reed switches and they'll work OK for triggering a low-current relay, but don't try to put much else through them. I had a memorable attempt to throw 16VAC reversing relays with them on the HVRR (magnet under the caboose) and it looked like fireworks going off under the train. Burned them out.
Yes, reed switches come in multiple flavors--NO, NC, latching, etc. The latching type are harder to find, and based on experience they're rather "fussy" to use. Better, IMO, to use a latching circuit.
Circuitron makes one I use for my freds, RS-2, Reed Switch Kit, 800-9102. Think I got mine thru Walthers. Bob.
I use latching reed switches that I got on eBay for my HO scale AT&SF "Fast Mail" rider, with marker lights on both ends. Instead of a reversing light circuit with diodes (I'm on DC) I'm using reed switches to switch between front and rear markers so when the train is backing up, the markers don't switch to the "wrong end". The reed switches are mounted side-by-side, so a swipe (or two, or three) of the magnet will switch it from front to rear or visa versa. The smaller magnets do not work as well as the larger magnets, which I hold about 1/2" above the switches, which are mounted in the roof. So, maybe try a larger magnet, with caution? Also try rotating them on their horizontal axis as the magnet should be more effective in certain positions. John
I tried rotating it, using a different magnet, etc. They work when I put them in a couple of LED circuits...an easy peasy light and another flasing LED circuit. For some reason, the same ones that work in the LED circuit, won't work with an incandescant bulb, they switch, but don't stay latched when the magnet is removed. I'm finding it odd that the same reed switch will latch in one circuit but not another. I guess that is where the ultimate question lies...why in one but not the other.
An incandescent bulb draws significantly more current than an LED. I don't know the characteristics of the reed switch you are using, but I suspect that the higher current draw of the incandescent bulb is enough to heat and soften the metal reed causing it to unlatch physically. As others have said before in this topic, they do not use reed switches for incandescent bulbs, just for LEDs.
