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Removing DCC Decoders
Arnaldo models OO and asks:
“I have been offered three cheap locomotives that are fitted with DCC but I operate DC. Is it simply a case of removing the chip to run them on my system, or will I need to do more?”
Supply your own suggestions under this post, or see what others have to say.
14 Responses to Removing DCC Decoders
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Buy a blanking plate. Replace decoder with the blanking plate to run DC or, check CV settings as many decoders will run on DC, but not all.
I Believe with the AID of JMRI, you may be able to RESET the DC OPTION back to ON, really depends on the LOCO, this may allow you to RUN IN DC MODE only
CV-29 has some BITS in it that you are able to alter to suit
Most modern decoders can be set to run on DC. Before removing them, I’d take them to a local model railroad club and see if someone there can reset them for you.
A locomotive that is DCC ready but doesn’t have a DCC chip will have a “blank chip” installed in the socket where the DCC chip goes. If you have those blanks, install them in place of the DCC decoder.
If you don’t have these blank chips, all is not lost as most DCC decoders will run on DC without you having to do anything. Go to the website of the chip manufacturer and check that this is the case.
You cannot harm a DCC chip by putting it on a DC layout. You CAN harm a DC loco by putting it on a DCC layout.
I don’t know about the locos you have but most DCC decoders made in the last few years will actually work with DC, as well as, DCC. I would try them before pulling them and see how they perform. A couple of things about the decoders; 1, the loco address must be set to cv=3, which is the default and 2, I believe a decoder can be set to never use DC, so if that was done it will have to be undone. Sorry, but I don’t know what the cv setting should be to use both. I am sure you can find it easy enough. I assume you don’t have any DCC equipment, so you will have to get assistance from someone who does to check the cv values and change them for you.
Most dcc decoders will run on dc. A few will not. Just try them out. If they don’t work, there is usually a dc plug you can get to replace the decoder itself.
There very well mat be a CV setting for either DCC or DC. If available and selected, the decoder will run on DC
I have multiple DCC fitted Locomotives but run DC and they run great. No need to remove the board. For example, I have a few N Scale locomotives from Bachmann and they operate flawlessly; lights work, slow speed excellent. However, by not running DCC, we are missing many sound features though, which for me, doesn’t really matter.
The best advice I can give is for you to find someone with DCC that can check the CV’s and reset them to operate on DC. Or, if that don’t work, find someone that can take them apart and see what needs to be done. If these are newer, then all the above advice is good. But if they are older, you might need outside help. Is there a club near you?
I’ve used these: digitrax.com/products/mobile-decoders/dhdp/
Agree most model decoders will run “dual mode”. I bought a used Loco with an older Digitrax decoder … so replaced that with the DHDP module – runs great on my DC layout. I believe this is for a 9 pin JST connector. Best try to research the decoder brand and model #.
If a DCC capable friend is available, reset CV 29 to allow DC running, or just remove the chip and install the original blanking plate if available. I always keep my blanking plates, and If I sell a loco I include the blanking plate with the sale.
Further to my earlier response, go to:
digitrax.com/support/cv/calculators/
Shows how the CV value is calculated to allow DC running using the locos’ pre-fitted with a decoder
Virtually any DCC equipped loco can be set to run on DC. Simply a matter of entering in CV 29 and setting the appropriate bit to accept DC running. Impossible to do this with a DC layout sou you will have to go to someone who is running DCC and have them program the decoder for you. Be forewarned the loco will hum and if left running for hours will probably fail and no longer operate.
If the locos you have were of the “Plug and Play” variety they came with a dummy plug that was removed to plug in the decoder. With the dummy plug restored the loco reverts to DC. The original plug is probably not available if the previous owner went to DCC but you should be able to find replacement plugs fairly inexpensively. Older locos that were not DCC friendly have probably had the wiring modified to run on DCC. While they can be converted back it is probably not that evident to someone who doesn’t deal with this regularly what steps to follow. It is not so simple as removing the decoder and putting it back together.