PM3 Heart Rate problems

[Tall Man]

Today I received a used HR receiver and transmitter that I bought through this forum.
My machine is a D1+PM3 running the latest update of firmware for that processor.
Plugged in the receiver and its cable and display went BLANK. Some times a vertical or horizontal line would appear and other times nothing.
After calming down and cleaning my pants I pulled the batteries and let the unit reset.
Came back to life and I started breathing.
Plugged in USB. Dead again. Reset again.
Now unit is running, USB link with Row Pro is working but NO HEART RATE data showing up.

Heart rate from this TX shows on my watch, TX->RX--> cable work on my PM2.

I suspect there is something wrong at the HR jack or on the board in that area.

Any wise tips? before I start pulling things apart?

Paul Y.

[Carl Watts]

It is pretty rare to have any problems with the PM3 in the Heart rate area, in fact I have yet to see one in the whole time I have been servicing them. Having said this it would apear you have a problem, however I would put it back in the PM2 and wiggle the plug round on the reciver and check it keeps working. There could be an intermittant fault in the plug cable of the reciver for it to shutdown the PM3 like that. Also try plugging it in the PM3 befor turning it on and see what happens. Also try plugging it in and unplugging it several times with the PM3 turned off as if it has never had a HR receiver in it the connections in the socket can oxidise and make poor contact over time.

If it is the older 2003 - 2007 version of the PM3 you could be unlucky and the supercap that leaks on the board which is just by the HR chip could have caused some corrosion.

[Citroen]

Have you checked the cable between the PM3 and the received. It's a stock 3.5mm stereo extension cable, so the easiest test is use an iPod (or other MP3 player) and make sure you're getting noise in both ears.

Put the cable back on the rower and check that the HR dongle is plugged in well. Check the cable is plugged in (fully home) on the PM3.

Check the battery in your HR belt, the PM3 needs a good strong signal, any softness in the battery and you'll get nothing on the PM3.

Check the receiver and cable on another PM2/PM3/PM4 if you have access to one.

[Tall Man]

Good News/Bad News
- Heart rate is working. After some close inspection I saw that heart rate plug was not fully inserted. Working swell now

- USB jack is fully broken off. Now I'm really sad. C2 site says buy a new PM. All the tails and the contacts on the board look OK.
Not sure I'm up to the soldering task but guess I could find a PCB repair guy.

Paul

[Tall Man]

Oh and the capacitor is OK.
Is that USB connector soldered on at the two tabs on the "shield"? Looks like those were pretty corroded and let the whole socket flex on the 4 little tabs.

Looks like I'll need to get the bifocals out.

[Carl Watts]

The USB socket is totally repairable even when it pulls the four tracks off the back with it on the earlier models of PM3.

Unfortunatly the sockets themselves didn't quite come up to a high enough temperature in the reflow oven when they were made and hence the solder did not make a strong joint. Probably due to the relativly large thermal mass of the socket. It can be resoldered to the board with the right equipment.

[Tall Man]

Hey I did it.
Bravely re-soldered the USB port onto my PM3 circuit board.
Not for the faint of heart but thrilling!
Now I am un-stoppable (as long as I can look stuff up on youtube)

Paul