| Show fixed condensers vastly important part has vital function to perform in every modern radio set despite alie widespread use of fixed capacities in every radio receiver and receiving system the subject is not thoroughly comprehended by the av radio fun when considering condensers the fan thinks mainly in terms of capacity this Is baily true of fixed capacities of rel value such as by pass and filter condensers cry few fans gle thought to beveral per items relative to fixed conden sers manifest a grbac effect upon lie utility of the capacitance anit A topic very seldom discussed Is the resistance of condensers this term Is alie balue of resistance fteres by the dielectric of alie con leiker to the flow of direct che dielectric medium Is the solid in sul atlon material located between ohp active metal surfaces in fixed ca this Is usually mica or a high grade of par affined or waxed piper hie litton resistance a ery important part in conden consider athons for upon it Is dependent alie breakdown voltage of the completed unit lower alie insulation re si stance of a condenser alie locci will be its break down voltage I 1 urther more the value of the insulation re si stance plays an extremely important part in alie calculation of alie factor of a condenser especially the units utilized in low frequency work fixed capacity fhe average fixed capacity Is usually subjected to high values of either D or voltage the higher the insulation resistance of the unit the can the applied voltage be without fear of breakdown and the higher the insulation resistance alip iless the leakage in the condenser coa denser and tho greater its operating efficiency consequently it Is paramount to main tain the insulation resistance of fixed capacities at the highest possible level consistent with the improvements in the various phases of radio ers improvements have also been ef upon axed cap corn measurements conducted in the laboratory of the wire less corporation upon capacities to determine the improvements effected upon present day devices over those manufactured at the advent of regular broadcasting showed the insulation resistance si of the present day products to be many times those of the hectic days after the advent of radio broad casting to quote exact figures the insulation resistance of several large elia condensers fixed of yesteryear yester vear wai found to vary between and ohms whereas similar condensers of present design showed insulation resistance values of 1250 ohms another important consideration to fans who utilize filter condensers and by pass condensers Is the distinction between tace two values I 1 ana who ignore the distinction 1 tween these two value do 0 o a hilr own risk this Is equally arre with bypass and filter the working voltage la tie volt uge at ahe con can be v a satisfactory factor ahe testing voltage on alie other hand Is the limit of operation for very short periods under no cir um stances should a condenser be con subjected to the testing volt ape anlue if it 1 it will break down in a very short time working voltage values alth alie I high volt ages being applied to the vacuum tubes in alie receiver detailed must be accorded the working voltage values of the by PASS condenser asod in the receiver it the condenser Is so wired into the circuit bit it Is sub ejected to a continuous load the work ing voltage ratings of the bv pass cm denser must be high enough to permit alie of the high voltage ganv complaints of blown bypass condensers leave no doubt been re celvid by manufacturers in all fair ness to the manufacturer the fan must realize tint each and every bv pass condenser has a work ing voltage measurements made upon various bv pass condensers for receiver aae showed a working voltage rating of to 27 withie higher voltages are encountered arf the receiver either bv pass con should be used the bv pass condensers arranged in slee or re u made to small af pf filter condensers the correct working voltage k |
