I realize this is kind of troglodytic and all that but for those still into DC, I thought I would post that there were earlier and later versions of this power pack made. I got curious when I got my regular N scale layout back up here after moving it from Rochester and decided to use two 2500's. I also have read posts by others online about some acting differently than others. In fact, one guy said he had four of them and three out of the four made his locos buzz quite a bit and the other one made them run much quieter. Sure enough, one of mine was the "buzzy" type and the other, the "quiet" type. I opened them and MRC obviously redesigned the 2500 somewhere along the line (when, exactly, I don't know. The earlier one appears to have a 8005 date code on the transformer (5th week of 1980) and the later one has a 9406 date code (6th week of 1994), although I didn't think they were still making the Tech II's by that date. Anyway, the circuit boards are very different. The earlier one has two adjustment pots on it, one adjusts the maximum voltage output and the other one adjusts the lower end voltage and where it gets high enough to start the loco. All the capacitors are mounted on the board. The later unit's board has no adjustments on it and is smaller. The evolution of board technology is very evident, also. It's much more refined/neater looking. One capacitor is mounted on reversing switch. The capacitors between the two versions are different values, also. An older locomotive powered by the earlier unit buzzes quite loudly right off the bat. Newer ones aren't as affected due to closer tolerances in newer locomotives. These older 2500's had a pretty aggressive pulse laid on top of the DC voltage. The pulse gradually reduces as the speed is increased although it doesn't completely disappear until a fairly high speed is attained. A loco run from the newer version is much quieter and isn't really much different from running on a straight DC pack. In fact, it's obvious MRC reduced the pulse amplitude fairly drastically. So anyway, just some info for those who may have wondered why all 2500's don't act the same. Doug
Were you able to look at the waveform on an O-Scope? I would be curious to see how they look at different speeds. Maybe 10%, 50% and 100% throttle. I built a DC Throttle out of a cheap DIY power supply kit and I got better slow speed performance from my locos than I did with the Kato throttle. When I looked at the outputs I was surprised that my DIY power supply was pure DC and the Kato pack had a sawtooth pattern.
Although I have used oscilloscopes many times in my life, I don't currently have one. If your locos are newer ones made after tighter tolerances were used and better designed motors, they may very well perform better on straight DC. Doug
That's really interesting Doug -- thanks for the post. Perhaps 35 years ago I somehow found myself in possession of an MRC Tech II 1500 and a Troller Transamp 1. They were both good packs; I don't recall any buzzing sounds emanating from my locomotives when using the MRC or the Troller. I still have both packs. I also seem to recall that when Troller was new, it was victimized by a strange surge in negative comments about its products, the first real threat to MRC's dominance in the field. People sometimes parrot remarks by others without thinking things through and I wonder if this lead to Troller's demise. My Troller ran just as well as the MRC. I still use my Troller handheld.
By coincidence, I have both those packs, too. I have had the Tech II 1500 since 1989 and it was the first Tech II I bought after having a 500N for years (which I still have). Mine never caused any buzzing either but I'm sure the 1500 has pulses much less aggressive than the 2500 and I remember it has always been said the 2500 had the most aggressive pulses of any MRC pack. I wonder if MRC got field complaints about that and hence, the redesign. I just got the Troller Transamp 1 from my stepson (he found it somewhere and bought it) and haven't had a chance to use it yet. I did plug it in and the track voltage light does work which is a good sign. Tim likes to go to all the MRR shows actually looking for Aurora Model Motoring cars and stuff but he likes trains, too. I gave him all my Aurora stuff I've had since I was a kid including a number 1302 set with everything still there and extra cars, Pit-Kit carrying case, extra track, and the obstacle course set to which my friends and I added strips of aluminum foil on top so the cars could go over the pieces at slower speeds without stalling. I remember all the attacks on Troller stuff too and I always thought it was probably from guys who tried to run 7 HO locos with a 1 amp pack. I recently read a complaint like that about an MRC Tech 4 because some guy tried to run several HO locos with it and it kept tripping the breaker. He didn't think it should do that. Doug
Hi Doug, I've been using MRC power packs or transformers since 1967. You could say I'm a satisfied customer of MRC power packs. Here is a short walk down memory lane of all my MRC power packs. My first DCC set And my current DC power pack. I really like the slow speed control of the new MRC THROTTLEPACK 9900, plus the hand held controller is a really nice option for switching operations.
Kinda like the automotive forums I see, where someone "tunes" a new car with aftermarket software and ruins their engine, then complains of poor engineering and that the Dealer won't cover the repair under warranty. Plus, posts are titled 'New Car Engine Failure' chasing away potential customers who don't understand what was done.
Thanks for showing us all those packs, Rich. The 100 was almost my first upgrade pack from a train set pack but somehow, I managed to be a little more patient and save the money to get a 500N. $14.99! That seemed like hundreds of dollars back then. I still remember riding back home from Nichol's hobby shop on my '67 Schwinn Deluxe Sting Ray with the box tucked against my side . I thought I would never get home. Now that I have my 4' X 8' N scale layout back up, I need to think about a walk around again . It would be handy. Doug
To me, almost every time there is a highly popular and successful product involved and suddenly one or a couple of people claim disaster and proceed to lambaste said product, said people end up being crackpots. Years ago, my late best friend (RIP) was the service manager at a motorcycle/snowmobile business and guys who had ripped up the front end/track by running their snowmobiles over tree stumps or broken fence posts buried in the snow, would come in and raise holy h**l because he wouldn't repair the snowmobile under warranty. They would try to claim a well-built snowmobile should be able to withstand that sort of abuse. Doug
I had a similar issue with a Jet Ski that I repaired. The repair was expensive and almost the cost of this ski. It was an old ski that was pretty much junk anyway. But I did the best work I could with what the owner wanted me to do. I couldn't find the damaged gear, but I found an engine that had the gear already installed and the new engine was in much better condition than his was. Replacing the entire engine was actually cheaper in labor than replacing the gear so he said yes on the engine but no on replacing the starter. The starter gear had also been damaged but it was not missing teeth... just chipped a couple. I told him then that if he didn't replace the starter I could not guarantee that the starter would not damage the new gear. He didn't want to spend another $100 on a starter. OK. Well he got the ski back out in the lake a couple times then it happened again. He brought it back to me for warranty. I removed the starter and felt the counter gear... yup missing teeth again!. The starter was also chipped up even more than before. I told him there is no warranty, the starter he didn't want to replace damaged the counter gear again and again that gear is no longer available. He wasn't happy. I didn't charge him for the diagnosis but I wasn't going to be out for this repair either. I eventually did find a counter gear and the seller knew this gear was next to impossible to find as he wanted $100 for it. Also I could not find any starters for this engine so with out the new starter it would not do any good to put a $100 gear in it. Oh well... He later brought me a more modern ski that suddenly would not run. He said he went to leave the beach and it just died and then nothing. I crawled under the trailer and looked into the jet... yup there was a rock stuck in the impeller. I was able to turn the crankshaft and free the rock, and amazingly it started right up. I wasn't going to charge him but he insisted and gave me $50 for my fixing the new ski. I didn't see him for the rest of the summer, but I'm pretty sure I will see him next spring because he doesn't know how to store watercraft over the winter.
I have a friend who runs a small sideline business out of his garage fixing personal watercraft engines. I once asked him, "How do people keep their lawn tractors, watercraft, motorbikes, cars and weed whackers all maintained?" His answer was a simple, "They don't."
My late father-in-law and I used to run a part time TV repair business in the seventies. There were customers who practically tore your head off for charging them 20 bucks to replace a power cord. They were expecting maybe 2 bucks. And then, there were the other kind of people. One guy I worked with on my other job (at Hormels) was also a farmer. He farmed during the day and worked at Hormels at night. He was kind of gruff all the time from being tired (I don't know how some of those guys did that). He and his wonderful wife had a big RCA console TV/stereo and I repaired it a couple of times. He would ask me how much he owed me and when I told him, he pretty much doubled what I wanted and he and his wife would say, "You're staying for supper, aren't you?" They are both gone now. Doug
Who else on here mastered the technique with the old MRC 500's with starting a loco/train on pulse power and then switching to full power after it got going and simultaneously turning down the throttle to just the right spot so the train would neither jerk to the higher speed nor slow down too much? Doug
Oh, that's funny -- I'd forgotten all about that technique! A routine part of train operation. I think I still have my old 500, but it's pretty banged up after numerous moves.
