Does anyone know if the newer QSI decoders have improved low speed control over earlier ones? I have an Atlas HH600 that has excellent low speed control and a BLI SW7 that has decent low-speed control (upgraded a couple of years ago to add BEMF following the settlement with MTH). As noted in previous posts, my Walthers FM H10-44 will not go more slowly than 2 SMPH no matter what CV's I tweak. I am debating whether to install a newer QSI decoder (cheaper and easier solution if it works) or to bite the bullet and purchase a LokSound 3.5 decoder (the closest sound available for this is an FM trainmaster). There is plenty of room for a decoder and I can replace the speaker with a 100 ohm speaker, installing it in the same location (fuel tank). My four LokSound equipped engines have outstanding low-speed performance. This would be #5. Any insight or info would be appreciated. As of now, the engine is "deadlined;" the HH600 is getting the most use right now!
John
John.
Before spending money on a new decoder I think a little troubleshooting is in order. With the sound muted and DC enabled in CV29. Take an amperage reading on DC when the loco tries to start. Disassemble the loco and check the trucks for free rolling, bronze bushings have lube, hair and dust buildup on the axles. Idler gears are good and turn easily. Check if the drive shafts are in phase. The worm gears do not travel forward and backward but turn easily. Check the motor for dry bushings, dirty commutator, brushes are in good shape. Broken armature wire, Magnet rubbing. Maybe a high torque low RPM motor will be a better fit then the cheap stock motor. It could very well be the gear ratio is too high and the motor struggles to start. A new decoder will not make a poor running loco better just more expensive.
Pete
I pray every day I break even, Cause I can really use the money!
I started with nothing and still have most of it left!
Pete,
Thanks for the suggestions. Th engine runs very well and steadily at 2 SMPH and with CV5 (deceleration) set at 30, it will coast to a smooth and gradual stop. It runs at about .03-.05 amps (according to my RampMeter). The unit is lubed and has no lint in the wheels or mechanism. The BLI SW7 had poor low speed as well until I replaced its chip with an updated BLI chip. The worm and gears seem fine, It may indeed be the motor but the very chep 3 pole motor in my two Bachman 44 tonners run very well and smoothly even at .5 SMPH with LokSound decoders. I might replace the motor, as you suggest but it may indeed be the earlier version of the chip. The HH600 creeps at .5 SMPH as well. Even an old Atlas S-2 with a Loksound decoder has excellent speed control, even though it draws .06-.15 amps.
I really appreciate your help.
If this is an early QSI there should be an upgrade chip available for it with RTC and BEMF. You said you had a newer QSI equipped loco? Maybe try a chip swap temporarily to see if it improves performance. My latest QSI equipped loco is the BLI I1sa. It crawls so slow if it were not for the chuff I wouldn't know I left it in speed step 1. This engine has the version 7 chip. My older M1a with version 2 chip crawls very slowly also. It does not have RTC and BEMF. The standard throttle with 128 SS has been very satisfactory and I see no need for an upgrade chip. I did have a newer Athearn RS3 that would jump start and could not get it to start slowly. I did as I suggested earlier except to the motor replacement. On that model I trimmed the brush springs like we did with the old Blue Box units and now it is smooth as silk.
Thanks Pete,
I just might tackle that project tomorrow. It can't hurt!
John,
I bought one of the new Atlas 600/660s recently and I was quite impressed with the low-speed response of the Q2 decoder in it. That puppy crawls! I found it quite a bit better than the older (but upgraded) QSI decoder in my BLI 2-8-2 Mike and better than my BLI 4-8-2 Mohawk. I have also found the the Q2 decoders are more sensitive to dirty track.
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
Tom,
That'swhat I was thinking. The H10-44 is over two years old (or whenever the FM switcher first came out) and is a Q1a. I hope to see if QSI has a Q2 with FM engine sound available since the Q2 in the HH600 works so well. The HH600 is excellent, isn't it! I hated applying the truck chains however! Aggh!
QSI had to disable BEMF in their decoders because of a lawsuit by MTH a couple of years ago. They eventually reached some type of settlement and reinstituted BEMF. Perhaps your older QSI decoder is one with disabled BEMF.
What version of QSI decoder do you have? I'm sure there are setting for voltage kick or equivalent to run at slower speeds.
Springfield PA