I just installed 3 digitrax decoders into Proto 2Ks: an F2 a/b and an S1.
The F2 a/b is basically plug and pray, but I had to put a resistor in on the light for the a unit.
The S1 required that I take out the engine solder a wire to the nut that retains the brushes, solder resistor son two lights, rewire and then plug and pray. I broke a light bulb putting it back together.
I tested them on DC.
All three rans sluggish and hesitated. It took a lot of powewr to get them up to low average speed. The s1 lost all its smoothness at lower speeds.
The both the a and b unit also jerked. Then the b unit died. It had made 6 or 7 laps, some on its own some as a consist. When it though, the Tech II would not light for power. I retested both the a unit and the S1 and they still worked–if you call running slow and jerking running.
Sounds like you have some wires crossed, or something. What decoders did you use for these? All my P2K’s have Digitrax DH163L0 and they run fine under DC power. My 2 Stewarts have TCS T1 decoders and they too run fine under DC power. I can tell, especially for my Stewart DS4-4-1000, that the old rguar HO pack I have has too low a resistence in the throttle rheostat - the sucker takes off like a scalded cat. Under DCC it runs real slow - under a better DC pack it would likely also run slow, but I’m not about to go buy a really good DC pack just to use for occasional testing.
Also, which Tech II do you have? It could be the low end pulses they put out automatically that is confusing the analog conversion in the decoder. Do you have the simple cheapy power pack that came with the Hogwart’s set? Try running with that one. A decodered loco will take a bit more throttle to get it moving that the same one without, there is a slight voltage drop thought he output drivers on the decoder, but it’s not so drastic that you would now need 3/4 throttle where the loco used to start at 1/4.
The one unit stopping after a while leads me to believe it is miswired or draws too much current for the particular decoder and it’s overheating. Although AFAIK, only Digitrax decoders have any form of thermal overload protection in the decoders, and then only in the Series 3 Premium decoders. Other decoders would simply fry the decoder and be done with it.
Space, I can’t remember, do you have a DCC system yet? I ask this, because I have learned the hard way that it is always a good idea to put a new DCC decoder installation on the programming track of my DCC system first before exposing it to the full voltage and current of the main line. Any problems in decoder installation can be identified on the safe programming track without the risk of smoking the decoder if there is a short anywhere. I don’t run DC anymore, but noiced on my first installations that the loco’s did run slower than without the decoder. Could the jerky movement be due to the decoder equipped loco’s being more sensitive to dirty wheels and track, even thought they are running in DC mode?
The decoder in the S1 is a dtxn143ip an N scale unit. The two in the F2s are also Digitrax, but I don’t remember the part number. They are probably pretty good. I remember that they have 128 step and the cost $27 from Tony’s. I got Tony to recomend it.
I am taking them to the club tonight and run them on that system. The Tech II is a 1400. It does not have the pulse feature (I’m pretty sure.)
Dual mode DCC’s take about ~8 volts DC to get started when run in analog mode. Once it does get enough power it looks up the “Start Voltage” in the CV register (check your docs that came with your decoder) This may be too high for your engine and may need to be lowered using a programming track.
So here’s what happening…you crank it to 8 volts and the DCC powers up, you give it more juice and it gets going with too high a voltage causing a “jerk motion”
I took the 3 Protos and the two DCC trains I got to the club tonight to air them out. The SW1 worked fine and got a workout helping me trouble shoot the passenger station that will be my (and my new Broadway E7A’s home.) The E7A is awesome but load. I’ll have to turn it down. My favoritie part is the metal wheels scraping as it slows to a stop. The F2A worked fine as well.
The F2B, the one that died after 6-7 laps around a small oval track, would not be recognized by the system on the program track.
The IHC 4-4-0 would test as “good” but would not be recognized on the main. I took it home and tried to run it DC and it stayed put. However, unlinke the F2B, it did not trip the transformer. The green light came on like it was getting power.
So 3 out of 5 are working.
I’m hoping you guys can give a hint. The guy at the club tried hard, but was obviously no expert.
Hey, you’re making progress. That’s an encouragment! [:)]
Chip, did you even think that you’d be at this point on 12/27/04: Installing DCC decoders in 5 locomotives and 442 posts under your belt. I think we should start calling you SpongeBob. You’re soaking up things at an amazing pace…
I only did 3 and the one that failed was the easies, only plug and prey. Didn’t even have to solder a resistor to a light because is doesnt have one. As for for soaking…I’m making my share of mistakes. I know that 4-4-0 is solvable–that’s my daughter’s train. Gotta figure that one out.
I think the E7B decoder is toast at this point. If it tripped the power pack on DC operation, there was most likely a short somewhere, and decoders don’t like shorts.
It COULD be a short with the track pickups - try removing the decoder since it’s a plug in type, and see if it shorts the power pack then - with no decoder and not replacing the original jumper plg, it should just sit there and do nothing. Then try putting the old jumper back in and make it a DC only loco again, and see if it runs.
Sompe Proto2Ks have some wiring issues with the decoder socket, but I am not aware of the E7 being one of those.