2_m_TO_BROADCAST_BAND

Published:2009/7/16 3:52:00 Author:Jessie | From:SeekIC

Permits tuning to 2-m (146-MHz) amateur band with ordinary AM auto radio, for monitoring FM repeaters and other 2-m amateur stations. Article stresses importance of shielding, compartmentalization, and RF blocking along power lead to prevent bleed-through of broadcast stations. Separate 9-V battery gives long life if converter is turned off when not in use, because drain is only 25 mA. L2 is 4 turns No. 20 on 7-mm slug-tuned form, with 2-turn link L1 at low end and tap 11/2 turns from low end. L3 and L4 are 3 turns No. 20 on 7-mm slug-tuned form. L5 is 20 turns No. 30 on 4-mm solid ferrite form. Y1 is 48.5-MHz third-overtone crystal. Convener gives good reception of both AM and FM stations on 2 m, with sharpness of receiver IF tuning determining ability of radio to slope-detect FM signals.-J. R. Johnson, New Improved Repeater Monitor, 73 Magazine. Dec. 1976, p 106-109.



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