WJW wrote:
Hello...a quick question looking for a good suggestion/solution/answer,

1) I have a small rural nursing school;
2) I have a $500 electronic stethoscope (micro-battery powered) that can
hear/play/record sounds using an I-Pod by using a direct wire/plug into
the I-Pod external microphone jack;
3) I-Pod sounds are very weak and you have to be within inches to hear
the sound during playback;
4) I need a room full of 10 students to hear the sounds from the
stethoscope;
5) I connected it to a wall-plug store-bought powered I-Pod speaker
sound system and it worked great...everybody in room could hear the
sounds fine!;
6) Was then informed it could possibly be a major shock hazard (110
power from wall through speakers to stethoscope to person wearing (ear
pieces) and to patient's chest (diaphragm);
7) So...now I'm back to Step 1 & 2...

Any suggestions on how I could truly prevent a surge danger for under
$100 bucks so that I can safely use the stethoscope and the powered
speaker system? Would an automotive quick-jump power pack with 110
inverter work or would the danger still be present? Is there really
even a danger in the first place?

Thank you very much for your wisdom, advice and expertise!

William in Colorado

Just isolate the patient electro-mechanically from the stethoscope by
placing the probe in a Plastic Baggie. The probe is most likely Plastic
or Bakelite with a plastic or rubber hose anyway, A thin layer of
plastic sheeting will not affect the acoustics !

Yukio YANO