Can anyone confirm how easy these are to damage?
I spent several days debugging an HM2 build that had low output and was super thin and trebly sounding. I DID rock before boxing, but I tested with an optotron board already wired up. I've now removed the opto board and the HM2 is working perfectly. H11f1 had been sourced from smallbear FYI
Is it likely that I had killed the opto? And any way to test this?
I can check voltages and resistance on the opto if that will help ...
Are you sure its the H11F1 and not something else like a weak solder joint or wiring?
I've yet to kill an H11F1...but it can be done I'm sure...
Josh
I thought the same thing so I reflowed all the solder joints, and pulled the wiring apart and rewired it, no joy.
I'll replace the opto this evening and see if there's any change
Bad switch maybe if the other opto doesn't get it working...
I did consider that too, the switch checks out when testing for continuity, but I have a spare so try that if the opto replacement is no good
Then its doubtful its the switch...
That's what I thought. I'll report back later
try measuring the resistance across pins 4 and 6 of the H11F1 when the effect is engaged. depending on your CLR and the LED it could be that the optoFET has a too high resistance.
I'll be interested to see where this thread goes. I've tried the same opto board twice and also used SB H11F1's. Neither worked, but both effects work fine in testing rig and with 3PDT switch. ???
I ended up using a new board, opto and switch, and it's working fine.
I've swapped out the opto on the first board I was using but haven't tested it yet. I tried measuring resistance across pins 4-6 as above, but I couldn't get a reading.
good to hear you're up and running!
Still wondering about the issue though. When you tried to measure the resistance, was the bypass LED on?
2 reasons I can think of not to get a reading is a) effect disengaged ->no internal LED ->optoFET is blocking ->maybe too high to measure or b)burnt/statically destroyed FET
No experience with opto switching but in the few build doc's i've seen there's an upper limit to the clr, could that be the issue?
dave
I'll double check, but I'm pretty sure I had used a 1k for the CLR, so that should be within spec
Quote from: davent on May 11, 2015, 10:45:11 PM
No experience with opto switching but in the few build doc's i've seen there's an upper limit to the clr, could that be the issue?
dave
No intent to hijack, but same issue: my CLR on both non-working opto's was 4.7K.
I had read somewhere a warning about not overheating these. Can't remember where.
After having done a couple of opto bypass boards with socketted H11F1's I decided I did not need to socket them and ended up with a fried chip the first time I tried ... and I'm not too bad a solderer usually ...
Went back to socketing.
Yes, they are heat sensitive.
Josh
and now I remember where I read it ... :-)