I am having trouble with the whistle controller in one of my RWs. When I had the RW apart, I noticed the the rectifier disc was shiny. A continuity test across the disc confirmed that oxide surface had been destroyed. I ordered a replacement selenium oxide rectifier disc from a parts dealer, and installed in place of the original copper oxide rectifier. I installed the shiny side inward against the rectifier bracket. Now when the whistle button is pressed, the whistle relay closes as it should, but the track voltage drops sharply and the transformer vibrates as if it is overloaded. However the overload is not a direct short. The contacts on the whistle controller are clean, so I doubt that is the problem. I tried my other RW, that has a good original rectifier, on the same loop and with the same tender, and it worked properly. I would appreciate any help anyone can provide.
It sounds like the shunt was not re-connected to the last(bottom) contact in the whistle button leaf switch or the base of the rectifier when the rectifier was swapped out. All the current for the track is going through the rectifier w/o the shunt shorted across the rectifier. This would present as you describe.
Rob
Rob,
Thanks! I'll check that out.
Thanks again. I found that the contact that touches the point for the resistor was bent and not touching the point when the button was pressed. I also resoldered all the connections in the transformer and it works properly now.
I'm just going from memory here - the whistle switch could be a slide switch on the RW... I'm checking now...
It is a 4 finger slide switch, and the resistance shunt windings are on the rectifier plate. The bottom 2 fingers will short the shunt across the rectifier disk at the bottom of the button press.
Did you preserve the shunt windings? This should be your problem.
Our posts went up at the same time!
I'm glad you got it fixed.
I like the RW, I think it's easier to use than the much-celebrated 1033 and better looking, it's certainly more powerful. It has that nice sloped front and looks great on a control panel.
Bob Nelson
Bob,
The rectifier I purchased is a repro part (1041-13). This is the disc that most parts dealers sell. On the list I ordered from, it was described as a selenium oxide rectifier disc. Yes, I would have preferred copper oxide, but I haven't seen any NOS 1041-13 rectifiers for sale. I checked my local Radio Shack for silicon diodes, but the highest rating they stock is 3 amps. I wasn't sure if that would be sufficent. Do you know what rating I would need? Thanks for any info you can give me.
A selenium or copper-oxide rectifier the size of the one in a Lionel transformer should be rated at only a couple of amperes continuously. The Radio Shack web site list this 6-ampere diode, which should be plenty big. It doesn't have to carry the full transformer current; and the current drops substantially when the shunt is connected.
http://www.radioshack.com/product/index.jsp?productId=2062591&cp=2032058.2032230.2032269&parentPage=family
I googled the part number and indeed saw it described both as copper oxide and "selenium oxide". But I also found it listed as "aluminum rectifier", which is absurd. I wouldn't be surprised if you actually bought a copper-oxide rectifier from someone who doesn't know the difference. Is one side copper colored?
The side that goes against the plate is shiny silver, the side that the speednut touches is a grayish-silver color. Thanks for the help.
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