If subject has a perfectly healthy heart, wrist-to-wrist placement is more convenient. Never use any electrode larger than 1-1/8" long by 1/8" wide to avoid wasting current on surrounding tissue. Confine exactly to blood vessels ONLY. Add a drop of salt water to each electrode's cotton cover ~every 10 minutes to keep electrodes thoroughly saturated during entire session.

Now rotate amplitude control to MINIMUM (counter-clockwise) and plug in electrode cable. Subject now advances dial slowly until he feels a "thumping" and tingling. Turn as high as tolerable but don't advance amplitude to where it is ever uncomfortable. Adjust voltage periodically as he adapts or acclimates to current level after several minutes. If subject perspires, skin resistance may decrease because of moisture, so setting to a lower voltage for comfort is indicated. Otherwise It is normal to feel progressively less sensation with time. You may notice little or no sensation at full amplitude immediately, but feeling will begin building up to maximum after several minutes at which time amplitude must be decreased.
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