The Bridgeport times and evening farmer., 1922-04-03
HOW TO MAKE RADIO SET
 About The Fixed Condenser

New York, April 3.-The action that results from applying a current to two or more conducting surfaces, same being separated by a dielectic ! (n1ica sheets, glass or paraffin paper} ] {see Fig. is employed in many ways in radio circuits. Such a device is call ed a condenser, and is said to have a certain capacity or so many micro farads, depending upon the number and size of the conducting surfaces and the dielectic separating them. This may be of a fixed or variable ca pacbty, depending upon tSe construc- ton. If the elements are stationary. it will be of a fixed capacity, and If they can be moved at will it will be lof a variable capacity.
 Since ours is a single circuit re- ceiver employing a crystal detector or rectifier, it will be of help to em- ploy a condenser of small capacity across the telephone receivers which will have the effect of taking the weak electric impulses which after Ibe:ng rectified by the detector are of an Intermittent direct current na- ! ture and storing them up in the con it discharges them in Q more even ] manner in the telephone receivers, which will have the effect of increas- 1 ing the signal a1ldibility which is all way desirable.
 This piece of apparatus is very simple and easy to cor1strut. but care must be taken ,3s to smooth 10th out out that all sheets of foil are uniform.
 Following Materials Needed.
 A condenser for our purpose should have a capacity of about .002 micro farads and the following ma terials will be needed:
 binding posts.
 1 hard-rubber base 1-4 of an inch thick, 3-4 of an inch wide, 1-2 inches long.
 hard-ruhber cover Is of an inch thick, l 5-S inches long, 3-4 of an inch
 sheets of tfnfotI 1-2 inch wide 1-2 inches long (which can be pur- chased from a florist)
 ' sheets of mica 3-4 of inch wide. l inch long. .0Oo thick.
 To construct. drilF four 5-S2 inch holes in the hard-rubber base as shown in figure 9. Now take the tin foil strips and in one end punch holes to take the binding post ma chine screws, allowing about 1-15T of an inch wall at the end. Build con denser up in this fashion. Take the two binding post machine screws and mount them in base as shown. Take a piece of mica. sheeting and place it 3-4 of inch from either end. Now take piece of tnfoil. passing machine screw through the , hole on the right Now take another piece of mica sheeting. placing it df- rectIy over the preceding one. Then take a piece of tnfOIl and place it over the machine screw on the left end and follow these opera tions until you have used the seven sheets of tinfoiI and mica sheeting. You will see by this arrangement that you have alternated the tinfoil strips each time. You will then have three strips of tinfon connected with the binding post on the left side and four on the right. and will end by having a piece of mica on top of the last tfnfoiI strip. Now take the cover and drill two holes to take binding post machine screws, and assemble as shown in figure g. Tighten up on the binding posts so as to compress the tinfofl~and mica sheet1ng, there coud enser.
 THE ORACLE.
 G. Jennings. Detroit, wants to : sknow-If there are any restrictions e against an amateur operating a transrnitting station.
 A. All radio transmitting stations are licensed by the Government. Would suggest that you get in COG raupication with the radio inspector. Federal Building. Detroit, and re- quest him to supply you with a copy Sof the rules and regulations govern ing radio telegra phy, and application blanks for amateur station and operators license
 A. Snyder, Cleveland sends. in 6 long letter in which he asks may he operate a telephone broadcasting station which he intends to install in a department store for publicity pur- poses.
 A. Suggest that you get in com rnunfcation with the radio inspector quarters are at Detroit, Mich, and make application for station and operators license
 CTornorrow' article will describe the telephone receivers.) cDr .<rz xrr0N