Mc In

LI - 6T NO. IS tNAM.,C.Tt 3/8 h LG, « 1/4" DIA.

1-2,1-3+1,5 - J5T NO. 24 ENAfcl., LG. * \/4 " DIA.,BRASS SLUG, TAP AT 3-1/2 T

L6 - .G2KhftFC OR 1ST NO, 26 ENÀM., 3/SN * 3/l€" DIA,

DI.DZ - MINIATURE COMPUTER DIODES {TYPE UNKNOWN), WITH LOW FWO, RESISTANCE & LOW CAfiftCrTANCE

Fig. 2, Low noise 50 mc converter. The transistors ore 52tf Tl-XM05's.

L6 - .G2KhftFC OR 1ST NO, 26 ENÀM., 3/SN * 3/l€" DIA,

DI.DZ - MINIATURE COMPUTER DIODES {TYPE UNKNOWN), WITH LOW FWO, RESISTANCE & LOW CAfiftCrTANCE

Fig. 2, Low noise 50 mc converter. The transistors ore 52tf Tl-XM05's.

into the receiver front end or about 7 volts peak across a 50 ohm circilit. Scratch one transistor! If your antenna relay has 50 db isolation in terms of power, then a K\V of peak power would only put ,7 volt into the receiver and the transistor might survive; Buy expensive coax relays that have good isolation especially if you operate with high power at 432 mc where antenna relays really lose db's of isolation,

About this time someone always asks why use transistors when tubes will cure this problem in the receiver front ends. The answer is that a receñí transistor costing about 52 cents will have a better noise figure than tubes costing 10 to 100 times as much, A lower NF always means more readable signals except perhaps in areas of high man-made noise, Even in high noise level locations, a low Nl' receiver and noise blanker system will help as

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