2016-10-21, 16:34
(2016-10-21, 08:21)DrRobin Wrote: I have found the schematics. It looks like a problem with one of the multiplexers or signal lines when the filter is selected on the E channel. I will have to trace through with a scope probe.
Does "been all around the chip" mean a visual inspection or a reflow of each pin with fresh flux? Apart from the chip I missed actually soldering a complete side (Doh!) I had "fun" with one of the others, every pin looked well flowed and connected but a reflow cured the problem so obviously something wasn't properly soldered. I have a feeling that there is some form of protective substance over the bare solder or plated areas as putting the through hole stuff on didn't "take" as quickly as I'd expect.
As for settings that's just getting a balance between the conflicting variables: interference, noise floor, bandwidth (faster rise time), filter delay, etc. For the last couple of days I've been in manual with minimal filtering (54 kHz on Ch1 (null to Anthorn), 19kHz on Ch2 and 54 kHz on the E-field. It was working quite well. Note "was" I've fiddled with antenna orientation and given it a supply earth connection today and it doesn't appear to be working as well as it was. B-(