Hi JB61264,
For a test, what you could do is, set all A, D, S & R knobs to for example a small value, let's say at 2 but not at zero, please! As Catwavez already mentioned, make sure you provide a gate signal to the gate input and then for example connect the out of that ADSR to the CV input of a VCA. If you have a Doepfer A-130-1 or A-131-1 then connect it for the sake of keeping the test simple to the CV1 input.
Then feed the VCA with some music, try to keep the rhythm of the music and the gate signal you sending to the ADSR in about the same tempo and then you should hear something coming out of your VCA. Once that works, try to play with the ADSR knobs and you should get some results.
Make sure that the gate signal that you feed into the A-140-2 isn't too extremely fast. For the sake of this test purpose provide a rather slow gate and then test it. Once you can confirm the ADSR works, you can increase up the gate speed of your preference. Note that Doepfer ADSRs (at least the A-140-1 that I have) can't cope with extremely fast gates.
If you are looking for a nice snappy EG (that can handle fast gates) then consider the Hikari Instruments - Triple AD as a second EG and use your Doepfer dual ADSR for the more slower gate stuff. I am not saying that Doepfer can't handle fast gates, it can but perhaps not at super speed (if that's what you are looking for). At "super" speed, the LEDs might not lit up. At extreme low ADSR knob settings the LEDs might not lit up either hence my advice to start with a slow gate first and all knobs set to two (2) for example.
Good luck with the troubleshooting and I hope you can manage to get your dual ADSR work. Kind regards, Garfield.
-- GarfieldModular
Awesome! Thanks for this, I did as you mentioned and its definitely working :)
Still wish they had some sort of reference 'manual' like Mutable has for their stuff...even if its just a page that has a brief label for all the connections and outputs...oh well, soldier on with the learning curve ;)
JB