Trouble reading cv8

[geoffb41]

Just purchased a used sound loco which was advertised as a Broadcom Limited but the paperwork that came with it is all Athern. Been trying to read CV8 in both Railmaster and on the Elite to work out what it is and can't get a reliable read

The last 5 reads have shown 24,74, XXX, 78, 255

Have cleaned the programming track and can read other locos fine.

There is no brand name on it except made in China.

Any idea why reading CV8 would give such strange answers.

[Chrissaf]

I assume you mean Broadway and not Broadcom. Broadcom produce component parts for PCs. Bluetooth & Wi-fi IIRC

These brands of Sound Decoders have a reputation for being difficult to read and write CVs. It is to do with the amount of power that the sound part of the decoder uses up and prevents the very low power programming command from being reliable. There is a product on the market that claims to resolve this issue. It is called a 'PowerPax'.

PPAX POWER PAX Programming track booster

I use a 'PowerPax' with my Elite and it completely transformed my CV reading / writing experience. The PowerPax is wired between the 'PROG' output of the Elite and the attached programming track and requires its own dedicated DC power supply [mine is 12 volts DC].

Take heed of the red text warnings regarding damage. The programming track MUST be TOTALLY physically AND electrically isolated from the main track. Any cross-connection will damage the PowerPax. I also have an additional 'on /off' power switch in the PowerPax supply so that I only power it up when I need to use it.

The PowerPax guide is reproduced below:

[geoffb41]

I have a soundtraxx PTB 100 program booster which does my other sound locos fine.

Just having no luck reading or changing CV's on this Broadway decoder.Most reads give XXX now and if a write works it is nothing like the value i enter.

After more testing today i think the decoder is faulty and going to organise a return unless you think the powerpax might solve the issue but be a pain to have to buy just for this one loco

geoff

[Chrissaf]

The PTB100 is doing the same job as the PowerPax so I concur that the issue probably lies with the decoder. Since you have a PTB 100, buying a PowerPax as well will be a wasted expense. If you haven't tried already. Try writing 8 to CV8 using your PTB100 to factory reset the decoder. If after three CV8 = 8 writing attempts the decoder has not responded and still has reading issues, then I too would consider it to be faulty.