okay got it, so it removes some of the lower boomieness of the audio spectrum since it wouldn’t be heard much anyway and allow more of the mid and highs to get through. my first impression was a audio filter as I am familiar with it use in that application but its good to know its blocking DC as well. I spent a few minutes reading this very basic understanding.?

Joe

On Mar 4, 2019, at 5:11 PM, iz oos <and2oosiz2@...> wrote:

Primarily it does block DC, however it attenuates somewhat more the lower frequencies (as 300hz) than the higher (3khz).

Il 04/mar/2019 22:56, "Joe Puma" <kd2nfc@...> ha scritto:

So it’s not dc blocking but a audio filter??

Joe

Kd2nfc?

On Mar 4, 2019, at 4:52 PM, iz oos <and2oosiz2@...> wrote:

0.1uF at 300hz has a reactance around 5000ohm, at 3Khz 500ohm, so it acts as a sort of audio high pass filter. If the cap has a higher capacitance the audio response is flatter.

Il 04/mar/2019 19:15, "Joe Puma" <kd2nfc@...> ha scritto:

The easydigi does have this blocking cap. .1uf

Joe

KD2NFC?

On Mar 4, 2019, at 12:05 PM, Playthatbeat Mrdj <playthatbeat303@...> wrote:

So things are actually worse when using a transformer to isolate the mic line? So things like the easy-digi etc. make things worse? this was not my experience at all. before using a transformer, i could not sustain the audio connection between my (horrible) single audio jack on my handheld PC, but after i could without issue.

So, it's possible that using easy-digi or a transformer is shunting the voltage on the mic line to ground, which could cause all manner of strange problems with the uBitx? Is this correct?