I have a condenser microphone boom attached to my headphones which I intend to connect to the MIC1 input this has a stereo jack on the end, however the ring and tip terminals are connected together. The MIC1 input connector has the Mic signal on the tip and the +2V biasing supply on the ring connection. Internal to the SunSDR2 is there a resistor (4k7) inline with the +2V and a capacitor (330nF) inline with the Mic input? If so my microphone would work if not I will need to add these externally to the SunSDR2.
Does anyone know the answer to this please?

I'm using a Yamaha CM500 headset with electret condenser mic for both my Elecraft K3 and SunSDRDX2. I just plugged it in and it works.

I use a condenser mic ( UHURU xlr ), phantom voltage supplied externally, and is plugged into Mic 2 via the RJ45 plug.
In the manual, Mic 1 is specified for electret PC mic.
I originally had a dynamic mic on mic 2.
Tom W3FRG

I measured the output voltage on MIC1: 5V, measured voltage with 15k load: 3.8V therefore there is a series 4.7k ohm.
Measured TIP to ground: low resistance then 16k therefore there is a series capacitor.
This means that was safe to connect my microphone with short between RING & TIP, this I did and works very well!

I using Mic 1 when having tranceiver in my boat electret Modmic to Rode Mic Go microphone and then bluetooth to Rode Mic Go dongel in Mic 1
At home, have tried Rode Dynamic Podmic to rj45 works ok
But now since about 4 months Rode Podmic to 2 external soundcards and Cakewalk software and settings are Mic PC
For me this is what I want and have several options with plugins but only use 2 to get the audio I like together with Sunsdr EQ
Svante sm6usu