. QST . 7^ by 10 H and the trans-mitter is 83^8 inches deep. Like other Viking units,the Adventurer is a product of the E. F. John-son Company. — Models 650 and 651 Matchmasters THE B & W Matchmaster is a piece of testequipment incorporating a dummy antenna,standing-wave ratio bridge, and powermeter in one unit. It is made in two impedancelevels matching the two commonly-used types ofcoaxial line. Model 650 being set up for 52-ohmlines and Model 651 for 73-ohm lines. The dummyantenna, which uses noninductively-wound wireresistors, has a continuous rating of 100 watts andan intermitte
. QST . 7^ by 10 H and the trans-mitter is 83^8 inches deep. Like other Viking units,the Adventurer is a product of the E. F. John-son Company. — Models 650 and 651 Matchmasters THE B & W Matchmaster is a piece of testequipment incorporating a dummy antenna,standing-wave ratio bridge, and powermeter in one unit. It is made in two impedancelevels matching the two commonly-used types ofcoaxial line. Model 650 being set up for 52-ohmlines and Model 651 for 73-ohm lines. The dummyantenna, which uses noninductively-wound wireresistors, has a continuous rating of 100 watts andan intermittent rating of 125 watts. Power in thedummy antenna is measiued by means of arectifier-type voltmeter, using a 1N34, connectedthrough a voltage divider across the dummy essentials of the dummy antenna circuits are shown in the accompany-ing diagram, in which the power-reading volt-meter and switching details have been interesting feature is the compensating cir-. The Matchmaster is a combination of dummy an-tenna, wattmeter, and bridge, and is useful fortestinR and adjustment of transmitters and antenna sys-tems. Dimensions are 834 by 8)4 by 634 inches. cuit for the dummy load, consisting of L\ (2spaced turns 34 inch in diameter) and the IOO-mm^-variable capacitor. The purpose of this circuit isto reduce reactive effects, particularly at the high-frequency end of the useful range of the instru- INPUT Lt OUTPUT
Size: 1661px × 1504px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectradio, bookyear1915
