Chris
Fellow Digitrax DT400 Radio RF users,
Ever lost control of your entire layout for a short duration? I'm
talking about all the radio throttles in the room.
I have found the cure. This is directed at users of the DT400
throttle running tetherless on radio, not IR mode. I have only
followed thru regarding RF use.
The fix:
Disable the Power Save mode by using Option #2 on the DT400. I set
mine at Hex X87. On the keypad, hit "Option"," Enter" consecutive
times until Opt #2 shows, and dial in the Hex value with the right
dial. Hit "Enter". Continue hitting "Enter" until it rolls out of
options mode.
The story behind it all:
The DT400 has a power save mode where the throttle goes into a
hibernation state (noticeably the display says "r-PS"), and only
comes back by making some kind of adjustment to the throttle, like a
speed change. I never thought much of it since the throttle jumped
right out of this power save mode, and I had minimal trouble
regaining control of my train. The issue goes much deeper than just
a simple power save state.
I run six throttles on the layout. Every 20 minutes or so all
tetherless operators would experience total loss of throttle control
and runaway trains were the order. It wasn't until we hooked up a
digital 900mhz radio with a signal strength meter and a high gain
antenna, that I was able to start tracking down the cause. A full
strength carrier is broadcast by the DT400 for a duration of about
20-30 seconds at a time, with different DT400 throttles
malfunctioning like this at different intervals (I call it a
malfunction, but it appears to be a design flaw IMHO). This carrier
was strong enough to block the normal traffic that was sent by all
other throttles, regardless of proximity to the UR91. I compared
three DT400 throttles that were bought over a span of more than a
few years, and all have similar MO, but not identical. One seems to
start malfunctioning shortly after going into power save mode, the
others typically take up to 20 minutes or more before doing the
same. The malfunction continues to cylce like this as long as the
throttles are allowed to stay in the power save mode. Since
disabling the PS mode, I have not monitored one incident on my
900mhz radio setup. Looking back the power save mode was annoying
anyhow, so I could have saved myself all the grief troubleshooting,
by disabling it from the start (lesson learned). I did have one
very brief conversation with Digitrax after my findings regarding,
and they did agree on taking the DT400 out of the PS mode.
Jeff