Show 2 52 i ia j IM 51 10 g r on s i 1 0 s s p sa power aines are arc still source of interference t dueby ane 0 o the most t insistent problems y in interference elimination Is that deal ing with disturbance which isleb originate on briare orore ban led by a power line hoe heiple heiP je indies numbers of such disturbances caulp cause anything from arf ad 0 occasional ca ahl click to a con continuous dilu roa roar r velch WhIch will drown out even a local glicr itis it Is being z received over nn an antenna A power gwei uric acts 6 as a 11 wit sort of guide to high frequency currents 1 be induced in duc edin in it much as they are in an antenna or to high frequency currents mai may result from nn an clec electrical lor disturbance on tile una line itself 4 atle phenomenon Is better known wl reles the difficulty in eliminating this type of ence Is due to the fact that it Is quite sli similar ullar to tile the signal which Is to be rec received elved for son bon uie the part of it that thai Is induced in the antenna circuit Is exceedingly difficult to eliminate the e portion of it that comes in over the power line inc and through the lie power supply device of tho revolver re on the other hand bond may tre fre be reduced deeven eliminated where the receiver Is of the power or electric type two small colls coils suil such a are used as in a radio frequency transformer may be connected isserles in series serles with the line and used n at radio frequency chokes one coll coil should bet be connected in series with each power lead near the outlet and the ibe two should be carefully shielded from each cash other and the receiver A tenth microfarad condenser should be connected acres the line side atthe of the arp two chocta chob ta qs Alt although hiigli what Is known a ag s a 11 s shield beld Is used between the ih primary and ee condary windings of the thew power tv v transformer it will be found that line disturbances are frequently present the two colls coils should be carefully mounted and insulated an input find and output plug should be used in other words tile the unit should be given the consideration that le Is given any device 1 I operates on the power line try any dist disturbance which can be definitely traced to an appliance or motor sh should he be remedied edat at the so source uffe by using one of the devices which are available an on the market marked these are usually a combination of bf condensers with with one or diore more sets which use an A battery with a B battery eliminator are subject to tile same type of interference thae ise Is e c A in 61 electric corfe receivers in this ase t the he high frequency part of the may frequently be eliminated in td by connecting a frequency choke in series with the radio fre qu quency ncy tap at the eliminator A half microfarad bypass by pass condenser should be connected from the ground to the afi choke ke term terminal loal on the receiver side |