31-03-2013, 07:13 PM
The temperature has returned to something approaching compatibility with life so it was time to have another go.
First I measured the DC Voltages. That didn't tell me much, ie nothing was desperately out of kilter, so I had to adopt the alternative approach of measuring everything.
At least after I'd unsoldered the PCB I could go back to the house to thaw my feet out.
I constructed a BoM and checked all the components - see attached.
Not to put too fine a point on it I suspect that the easy thing to do is to change all the Resistors, provided I have all the values.
The Capacitors, apart from the Hunts that I've already changed, should be OK, which is not surprising as they're all Ceramics. I had a minor panic with C518 which was miles out when measured in circuit, but OK when I took it out.
While I was at it I corrected a few typos that had crept into the Schematic
So, onward and upward.
Alan
First I measured the DC Voltages. That didn't tell me much, ie nothing was desperately out of kilter, so I had to adopt the alternative approach of measuring everything.
At least after I'd unsoldered the PCB I could go back to the house to thaw my feet out.
I constructed a BoM and checked all the components - see attached.
Not to put too fine a point on it I suspect that the easy thing to do is to change all the Resistors, provided I have all the values.
The Capacitors, apart from the Hunts that I've already changed, should be OK, which is not surprising as they're all Ceramics. I had a minor panic with C518 which was miles out when measured in circuit, but OK when I took it out.
While I was at it I corrected a few typos that had crept into the Schematic
So, onward and upward.
Alan
