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Henedce
11-02-2011, 05:41 AM
OK I built 50 odd DCSSR's earlier in the year , I seem to have about 12 with the same problem.
Plug into Renard no or very dim LED lights up
Jumping pin 16 on the opto to 15 13 11 and 9 all channels light
Checking pins 2 4 6 8 all 4 cycle on and off rubnning a 1 sec sequence
On the DC side checked voltage after the reg I have 5v
Cat 5 cable is a known good cable (double checked)
Pulling the opto for a known good one same result
Checked all resistor values with a multimeter all test right

thoughts ????????

LabRat
11-02-2011, 06:44 AM
... no or very dim LED lights up


Are you referring to the LEDs attached to the channel.. or the indicator LED that is on the board?

Henedce
11-02-2011, 06:56 AM
Are you referring to the LEDs attached to the channel.. or the indicator LED that is on the board?
Indicator LED

TimW
11-02-2011, 07:04 AM
checked for tarnish/corrosion on the RJ45 jack? ( can visually inspect or check for continuity between +5v on the controller and +5 on the board (can do this powered down)

Henedce
11-02-2011, 07:17 AM
Checked continuity on all 8 pins . all test ok . Checked input voltage from rj45 tests at 5v . At Indicator led it tests at 1.5v or there abouts .
Needless to say im stumped

TimW
11-02-2011, 07:52 AM
What opto chip are you using?

TimW
11-02-2011, 07:59 AM
Could it be dry solder joint(s) on the board?

Henedce
11-02-2011, 08:03 AM
Same opto is on 38 other boards with no problems .
Going to go over the solder joints tomorrow just to be sure.
Just tried replacing the indicator LED after rereading (bit of a long shot) what I posted her still no joy.

Henedce
11-04-2011, 07:00 AM
OK here is an update
with 13.5VDC in on a good board if I jump from + to pins 15 13 11 and 9 on the opto i get 13.5VDC then 8.5VDC when the channel switches on.
On a bad board it stays at 13.5VDC
Could I have a bad batch of resisitors maybe ??
They all test at 680Ohm but seems to be the only thing that could possibly be consistant across so many boards I did build in batches and looking through the boards it looks like it is the last batch I built.
I have 1 board that has 1 good channel and 3 bad

ABOVE IS WHAT I WAS TYPING UNTIL I WENT TO CHECK MY VOLTAGES.
Problem solved .680Mohm and .680Kohm are kind of different and make a big difference to the operation of the DCSSR

TimW
11-04-2011, 07:21 AM
But they are both .680 on your meter? :)

Glad you found the culprits.