The best condenser for this use is of about 1/2-microfarad capacity, which is ample for voice-transmitting purposes, while it serves to effectively bar the major portion of the generator currents.
The two windings are bridged across the cord circuit, with a 1/2-microfarad condenser in series in the tip strand between the two winding connections.
This arrangement also largely prevented through ringing, since the currents would pass through the 1-microfarad condenser and the 500-ohm drop more readily than through the two condensers connected in series.
Two 500-ohm clearing-out drops of ordinary construction are bridged across the cord circuit and in each side of the cord circuit there is included between the drop connections a 1-microfarad condenser.
The condensers ordinarily used in telephone practice range in capacity from about 1/4 microfarad to 2 microfarads.
In this the calling and the answering plugs are separated by repeating coils, a condenser of 1-microfarad capacity being inserted between each pair of windings on the two ends of the circuit.
In order to reach the other clearing-out drop the ringing current must pass through the two 1-microfarad condensers in series, this making in effect only 1/2-microfarad.
A one-half microfarad condenser is placed in the receiver circuit at each station so that the line will not be tied up should some subscriber inadvertently leave his receiver off its hook.
Two high-wound locking relays are bridged across the line, the cord strands being divided by 1-microfarad condensers.
As is well known, a 1/2-microfarad condenser not only transmits voice currents with ease but also offers a very high apparent resistance to ringing currents.
It made use of two condensers of 1 microfarad each, one in each side of the cord circuit.
The farad is a very large unit, and accordingly the microfarador one millionth of a farad is often used, though this must be reduced to farads before substituting in formulæ.
The direct currents of telegraphy are prevented from passing to ground through the telephone set during conversation by the 2-microfarad condenser which is in series with the receiver.
In the figure, AA are arresters, as before, GG are Morse relays; a 2-microfarad condenser is shunted around the contact of each Morse key F to quench the noises due to the sudden changes on opening the keys between dots and dashes.
The 250-ohm resistance connected across the circuit through one back contact of the telegraph relay absorbs the discharge of the 6-microfarad condenser.
Thus, a coil may give a ten-inch spark if worked alone, but on a capacity of one-thirtieth of a microfarad it may not be able to give more than a five-millimetre spark.
If any sparking takes place at the point of the stylus, a small condenser C' (about 1 microfarad capacity) should be connected as shown.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "microfarad" in a variety of sentences. We hope that you will now be able to make sentences using this word.
