Even in a very noisy environment, Model-139B still has the ability to determine quickly and precisely the positive and negative polarity of a loudspeaker、headphone、receiver and every single unit in a loudspeaker system. Model-139B also includes 3 sets of external input terminal

and selector which can be used to combine with other instruments, in order to measure the other features of a loudspeaker simultaneously. It is quite suitable for 100% Q.C. testing for loudspeakers in production line.

Characteristic

(1) Model-139B can determine at once the positive & negative polarity of a loudspeaker,receiver, headphone and every single unit in a loudspeaker system.

(2) Model-139B uses both the "positive" & "negative" polarity indicators, to measure instantly the positive & negative polarity of a loudspeaker, besides, to avoid visual error that causes the wrong determination of polarity, Model-139B is designed with the supplement of a beeper, which when buzzing, indicates the positive polarity.

(3) Model-139B can't not be interfered by the background noise, even in a noisy production line, Model-139B still can determine quickly & precisely the polarity of a speaker.

(4) Model-139B also includes 3 sets of external input terminal and selector which can be used to combine with other instruments, in order to measure the other features of a loudspeaker,for example :

(a) Model-139B can combine with an Impedance Meter / Freq. meter ( Model-152A ), to measure the impedance of a loudspeaker.

(b) Model-139B can combine with a Digital High Speed Fo Meter ( Model-7117C ), to measure the Fo value of a loudspeaker.

(c) Model-139B can combine externally with an Audio Sweeper(Model-7116C), to test the buzz, rattle of a loudspeaker, it needs only one person to operate, its quite speedy & convenient to operate. Users may use a foot switch to control the selection of either one set of testing item, to make alternate testing with loudspeaker's polarity (WF or M&T).

Model-139B

Pulse Testing Method.
Polarity :
Pos. polarity :Green LED indicator with beep sound.
Neg.polarity:Red LED indicator with no sound.
Sensor:ECM
Five selecting switches :
WF:suitable for the woofer.
M&T:suitable for the midrange, tweeter & headphone.
Ext.1~Ext.3 : For connecting instruments.
Dim.:28 ( L ) ×9 ( H )×21 ( D ) cm.
6.Net Weight : 2.5 KGS