ECG electrode impedance checking system as for emergency medical service
First Claim
Patent Images
1. A circuit for checking a plurality of impedances, the impedances having a common connection point, the circuit comprising in combination:
- a first frequency source;
first circuit means coupled to the first frequency source for providing a plurality of switching control signals;
a second frequency source, said second frequency being at least fifty times said first frequency;
first switching means coupled to the first circuit means and the second frequency source and controlled by the first circuit means for switching the impedances into ones of a plurality of configurations and coupling the second frequency thereto;
second switching means coupled to and controlled by the first circuit means;
indicator means including one indicator for each impedance;
enabling means coupled to the outputs of the second switching means and to the indicator means and reference means for enabling one of the indicators when the respective impedance is greater than the predetermined value of impedance.
0 Assignments
0 Petitions
Accused Products
Abstract
A circuit for checking a plurality of impedances having a common connection point as for use in an emergency medical ratio, where the impedance of each ECG electrode contact is automatically and sequentially checked during the initial calibration transmission, using the AC non-polarizing signal which is also used as the ECG subcarrier for the medical data telemetry. The ECG telemetry calibration signal is also processed to provide a sequential switching control. Poor electrode contacts are indicated visually to the paramedic in charge and thus can be corrected before ECG telemetry begins.
59 Citations
12 Claims
-
1. A circuit for checking a plurality of impedances, the impedances having a common connection point, the circuit comprising in combination:
-
a first frequency source; first circuit means coupled to the first frequency source for providing a plurality of switching control signals; a second frequency source, said second frequency being at least fifty times said first frequency; first switching means coupled to the first circuit means and the second frequency source and controlled by the first circuit means for switching the impedances into ones of a plurality of configurations and coupling the second frequency thereto; second switching means coupled to and controlled by the first circuit means; indicator means including one indicator for each impedance; enabling means coupled to the outputs of the second switching means and to the indicator means and reference means for enabling one of the indicators when the respective impedance is greater than the predetermined value of impedance. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. An electrode impedance checking circuit in an emergency medical radio apparatus, the circuit including in combination:
-
a first frequency source; first circuit means coupled to the first frequency source for providing a plurality of switching control signals; a second frequency source, said second frequency being substantially higher than said first frequency; first switching means coupled to the first circuit means and the second frequency source, and controlled by the first circuit means for switching the impedances into ones of a plurality of configurations and coupling the second frequency thereto; second switching means controlled by the first circuit means; indicator means including one indicator for each impedance; reference means for establishing a predetermined value of impedance; and enabling means coupled to the outputs of the second switching means and to the indicator means for enabling one of the indicators when the respective impedance is greater than the predetermined value of impedance. - View Dependent Claims (11, 12)
-
Specification