Differential Pre-amp/ADC

[sled]

hey,

I wonder how a schematic for a differential RX Pre-Amp/ADC on a VLF detector would look like. Most schematics use a single ended configuration, but why, are there no benefits using a differential front-end?

[moodz]

...alot of designs connect one side of the coil to ground ...

[mykaitch]

when you think about it, all op amps are differential amps...

[Skippy]

Presumably a differential coil would cost more, having to be wound bifilar. And the coax cable would be twin-core screened, also slightly more expensive. Cable microphony may be less of a problem. Fine-tuning the IB null may be harder, any small tuning loops would need to be on the TX.

[Carl-NC]

I wonder how a schematic for a differential RX Pre-Amp/ADC on a VLF detector would look like. Most schematics use a single ended configuration, but why, are there no benefits using a differential front-end?

Mostly there is no differential signal to deal with, so a differential preamp doesn't buy you anything. You could design the coil to produce a differential signal -- such as with a DOD or figure-8 -- but even then there may be no advantage to a diff preamp, and even a cost disadvantage.