6. Technical Specifications

Value
Characteristic
Units
Min
Nom
Max
Maximum amplitude of positive part of output impulse
V
25
40
Maximum amplitude of negative part of output impulse:
no load condition
V
250
350
under load (20 kOhm resistance and 2200 pF condenser connected in parallel)
V
70
130
Maximum duration of positive part of output impulse
micro-secs
320
400
Base frequencies of output impulses:
low frequency
Hz
60
medium frequency
Hz
100
high frequency
Hz
140
Deviation of variable output frequency from mean level during operation in the variable frequency mode
%
±20
Period of frequency changes during operation in the variable frequency mode
sec
30
Time required to change output intensity from minimum to maximum level
sec
9
Interval therapy:
Treatment
sec
3
Pause
sec
1
Time before apparatus automatically switches itself off
min
10
Battery voltage
V
7.2
9
9.5
Voltage at which battery discharge alarm is activated
V
7.5
7.9
Average time of continuous operation between battery charging
hrs
8
Size of apparatus without packing, not more than
mm
45x55x195
Weight of apparatus without packing, not more than
kg
0.5

The apparatus is powered by a Nickel cadmium battery, type Varta 5022, TR7/8, V7/8R (110mAh, 9V) or type "NIKA" (100mAh, 9V).


The form of the output electrical impulses is shown in fig.1:


Tv - period of output electrical impulse variations (frequency is equal to 1/Tv);

tp - length of positive part of impulse (defines intensity of treatment);

Um+ - amplitude of positive part of impulse;

Um- - amplitude of negative part of impulse;

t - time-axis.

Measurements are taken at the inner electrode relative to the outer.


Changes in the output impulse frequency during operation in the variable frequency mode are shown in fig. 2:


F - output electrical impulse frequency;

Fmax - maximum output electrical impulse frequency;

Fav - mean (average) output electrical impulse frequency;

Fmin - minimum output electrical impulse frequency;

T - frequency change period;

t - time-axis.

Maximum deviation (in percent) from the mean value is determined by the expression: (Fmax - Fav) x 100 / Fav.