New 2-8-2 sound value dcc loco

[jim margerum]

At an NMRA show this weekend, my friend purchased the new 2-8-2 mikado sound value dcc. It was taken to a test track to verify that it was OK. When it was put on a straight dc test track, it's lights flashed on both ends and there was a loud clicking sound coming from the speaker. The clicking and the flashing were in sinc. When the voltage was high enough, the lights were on solid and the sound started. The voltage at this point made the engine take off very fast.The test track had an old Troller unit for power.  It was then taken to a display layout that had very good dc/dcc controls. On dc, the lights still flashed, but the clicking sound was gone. It still took off way too fast at the start. It was then switched to dcc and the lights came on solid and the speed was more controllable. Is this normal for a dcc engine on straight dc? Two locomotives were tested and both ran this way. Thanks in advance, Jim

[Hunt]

An issue is the "old Troller" autopulse power pack.

The Sound Value decoder will work best in analog mode when using a high
quality, electronically regulated power pack, preferably one that supplies
smooth, filtered DC power. Older rheostat style power packs and pulse power
packs will result in erratic and unreliable operation and should not be used.

[bapguy]

A sound decoder needs around 6V to start. That leaves 6V to run on. Read any review of a sound equipped loco and you'll see this mentioned on how the loco ran on DC.  Joe

[ebtnut]

I raised this same issue a while back with my Mike.  I have an MRC Tech II for my test track and the loco exhibited some of the same actions you describe - lights flashing and some stuttering in the mechanism until the voltage got up to about 6 volts.  At that point the loco then performed OK, but only had the "chuff" sound.  When I took it to my club layout, which has a DCC section, the engine performed very well, with all the sounds and good speed control.  As noted, most all DCC decoders only perform basic functions and usually take about half the throttle to get them running.  And then you only have the remaining portion of the throttle for speed control. 

[jbrock27]

What model Tech II?