notch filter. Encyclopedia of radio electronics and electrical engineering
Encyclopedia of radio electronics and electrical engineering / Knots of amateur radio equipment. Filters and matching devices
Comments on the article
The notch filter shown in Fig. 1 is tunable with C1 from 28 MHz to 60 MHz and can be useful for suppressing TV1.
Fig. 1 Coil L1 - frameless, contains 10 turns of wire 0,8 mm on a mandrel with a diameter of 8 mm, winding length - 18 mm. Branches - from 4,5 and 5,5 turns. L2 - also frameless, contains 6 turns of the same wire on a mandrel with a diameter of 12 mm, winding length - 18 mm.
The design of the filter is shown in Fig.2.
Ris.2
Literature
- Television Interference Manual, RSGB, 1979.
-
Radio amateur KB and VHF 9/97, p.29
Publication: N. Bolshakov, rf.atnn.ru
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