Phil,

There's a similar problem reported on the Digitrax list, message
104253, where someone was trying to program with an NCE system. The
advice was to fit a load across a function wire. The OP never came
back to say if it worked...

A resistor in line with one SPROG output will not help in this case.
That's the fix for sound decoders, to limit the current, which isn't
usually required for SPROG.

Start with a resistor between a function output and the blue wire of
about 120 ohms and go down in value from there, or try a 12V grain of
wheat bulb. A LED+resistor will not draw enough current. This assumes
the decoder switches on the function outputs to generate the ACK pulse

Have you tried different programming modes?

Did the decoder actually program? Even though you aren't getting an
ACK, it may well be programmed.

I will be off-line for a few days, but please post how you get on and
I'll check when I return.

Regards,

Andrew

--- In sprog-dcc@..., "Phil Dunlop" <pndunlop@...>
wrote:
>
> Good Day all;
>
> I have the above set up, and just recently, like yesterday, tried
for
> the first time to program a digitrax TF-4 function only decoder.
> What a dismal failure, sigh.
>
> I've never had a problem with this set up before, done Tsunami,
> Loksound, Soundtraxx, and Digitrax motor control decoders, all with
> no problem.
>
> Don't know if it's a sprog or decoderpro problem. I tried direct
to
> decoder connections, and various resistor ideas trying to simulate
a
> motor load, etc. Decoderpro reports an error "stopping due to no
> locomotive detected". It's pretty adamant about it. It's not the
> decoder, I was able to program one on a digitrax programming
track.
> Did Digitrax design a decoder that only works on their system in
> spite of what the instructions say? Am I doing something stupid??
> Any ideas would be appreciated.
>
> Cheers
> phil d
>