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I built the voltage regs,and the 555 tx timing I put in the sync capacitor and transistor. When I checked the sync it wasn't working, it was free running on pin 2. Pin 6 had a exponential rising wave on it synced to the tx of course the 3904 was driving the wave form it climbed to 0 v and was pulled to -vb when the tx went. I pulled the charge pump and the waveform is still present.something is charging the collector of my 3904 to 0v if the emitter is -vb and the base during off time is -vb the collector left open should be ? Is it acting as a capacitor? Or should I be looking for a solder bridge?
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Pin 6 is connected to pin 2 on the PCB (U2). R5 is pullup. -
It is transistor behavior, pin 6 is not connected on the charge pump I was using which left the collector open. Interesting. I jumpered pin 6 to pin 8 so that r5 could pull up the collector and its beautiful. I just have to order the lt1054, pin compatible is just a suggestion it seems to some manufacturers.Comment
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