Jim,

What kind of power supply are you using? You need a regulated DC
supply and sound decoders in general can draw a lot of current during
programming. There is an issue with QSI V7 decoders (what do you
have) but this kind of intermittent behaviour can also be a symptom
of an unsuitable power supply. The resistor kludge isn't generally
required with SPROG but there's no harm in trying a low value in
series with one of the programming track leads.

Andrew

--- In sprog-dcc@..., "Jim Davis" <jimbdavis@...> wrote:
>
> Hi Gang,
>
> When I use my SPROG II to program QSI decoders (in Broadway Limited
> switchers and a Proto2000 GP9), it sometimes has trouble reading
> CVs. DecoderPro keeps trying though, and everytime it has been able
> to read the CV after another try or three.
>
> Any thoughts on what might be causing this? I realize that QSI and
> other DC-active sound decoders present problems when reading CVs on
> the programming track, but I find this intermittant problem to be a
> little odd. Interestingly, as I read more CVs from a locomotive
> during a single session, it "misses" less often.
>
> I've cleaned the track and the wheels, and the connections to the
> track are soldered. Do I need bigger wire/less resistance? I also
> recall reading a recommendation that a resistor be added to the
> program track connection for some DCC systems to improve reading
> ability.
>
> I'd appreciate hearing from anyone with similar experiences or
ideas.
>
> Thanks,
>
> Jim Davis
> Moscow, Idaho USA
>