2016-10-21, 22:17
Hi Dave,
Reflowed. I hand soldered them in and all of the joints are A1. I have over 40 years experience of soldering so you get to know a good joint. I reckon the open circuit is one of the components soldered at supply and just never spotted/tested before.
I didn't put a filter IC in H-3 and if I select the LC filter on this channel then it just shows no signal, not 50Hz noise so it must be an input open circuit, which has no pull down. My first guess is the second (o/p) multiplexer, but tracing through with a scope will pin point it. Sadly I am away for the weekend so it might have to wait until next week.
However, the H-field channels with LP filters and manual settings for gain are working really well.
I noticed your station working really well yesterday, picking up at long range, I would re-align the antennas back to where they were.
Robin
Reflowed. I hand soldered them in and all of the joints are A1. I have over 40 years experience of soldering so you get to know a good joint. I reckon the open circuit is one of the components soldered at supply and just never spotted/tested before.
I didn't put a filter IC in H-3 and if I select the LC filter on this channel then it just shows no signal, not 50Hz noise so it must be an input open circuit, which has no pull down. My first guess is the second (o/p) multiplexer, but tracing through with a scope will pin point it. Sadly I am away for the weekend so it might have to wait until next week.
However, the H-field channels with LP filters and manual settings for gain are working really well.
I noticed your station working really well yesterday, picking up at long range, I would re-align the antennas back to where they were.
Robin