Male Seeks Assistance With Recording Using Doctor's Scope

Clearwater FL

Description

I have a SLR digital camera with a mic jack and I severed a stethoscope and tried to insert a small Rode lav mic into the tubing and thought I saw the VU recording levels moving on the camera but I didn't pick up any bodily sounds when I plugged the camera into the computer. Do I need a different mic or scope or technique?