[BARC-List] CB sign on Divinity Ave, Cambridge (Harvard U)

[J. Forster]

Any number of ways. EKG signals are millivolts. If the 3 lead monitor is like powered, there could be ground loops (possibly through stray capacitances). If battery powered, it could be acting as an antenna.
Older versions could have fairly low or non-linear input impedances which could cause artifacts.

-John

Derek Scuteri wrote:

> Regarding interference with EKG machines,
>
> Patient with a 3 lead heart monitor on, now doctor orders EKG, placed EKG leads
> on, patient fairly still, notice "artifact" on the scope, try to troubleshoot to get clean
> non-wavy display prior to printing, not being successful, fellow workmate says
> the 3 lead heart monitor sometimes causes interference, the 3 lead monitor is
> temporarily disconnected, to my amazement "artifact" is gone.  How could a
> 3 lead heart monitor, which I though passively senses/receives signals from
> the body (neurologically speaking lets say action potentials ) cause inteference?
>
> Derek Scuteri
> Emergency Department Technician, EMT-B
>