Rechecked, the 5v side of the resistor goes to u704 pin 14 vcc. The other side goes to u702 pin 12 output.
All outputs to the mosfets h and l are connected to u704, PIN 1y, 2y,3y and 4y...is this correct? I expectet h and l at 1a and 1b.
So, i have made a bridge between r707 and u703 pin 2. Now i have square wave on a few Pins of u703. But nothing on u704.
Somehow there was a solder bridge under the cap. Found three cut traces. But still no connection between r 707 and PIN 2.
So, still not ok, but better. On 703 i have Signals. On 704 only at pin 2 and 11. Maybe the ic is damaged during soldering?
I have found that the 74Hc02's are picky and sensitive to heat or ESD (have not determined which). I get my chips from Mouser to avoid cheap counterfeits but still will pop one every now and then. I have been the most successful when remembering to put on the wrist strap and use quick drag soldering.
Thanks for the Info. At the moment i fed up from this amp. Next time i will try aggain. Can you tell me, which solder you are using excatly? Normaly i still use solder with pb. But i also have very small diameter pb free, with high ag.
- Status
- Not open for further replies.