KLM 27 Element UHF “Bandpass Yagi” Antenna Model KLM-420 .
Manual ForKLM 27 Element UHF “Bandpass Yagi” AntennaModel KLM-420-470-27This antenna consists of a 4-element broadband Log-Periodic surrounded by oneconventional Yagi reflector and 22 Yagi-style directors. The resulting antenna hascontinuous coverage with a uniform pattern, SWR and gain across the entire amateurUHF band from 420 to 450 MHz, making it suitable for FM operation in the 440-450MHz range, SSB in the 432 range, and ATV in the 434-440 range.The following pages are cleaned up 300 DPI scans of pages of the original manualsupplied with an antenna purchased in the late 1970s. These pages contain enoughdimensional data (element lengths, spacing, etc) to reproduce this antenna today.The original 3/8ths-inch aluminum tubing antenna elements had molded-on plasticmounting brackets/insulators. These brackets insulated the elements from the 1”diameter aluminum tubing boom, placing them about 1/8th inch above the boom.A possible approach to re-creating this antenna would be to use 1¼ inch diameter PVCpipe for the boom instead. One would pass the elements through 3/8-inch diameterholes crossing the diameter of the pipe.The log-periodic driven elements could be bolted to a piece of 1/8th-inch think G10glass-epoxy PC board with the right-sloping “zigs” of the log phasing harness etchedinto the top surface of the PCB and the left-sloping “zags” etched into the bottomsurface of a double-sided PCB. The back end of the driven-element PCB would extendjust enough farther back to also support the single reflector element behind the logsection. The forward end of this PCB would be fitted into a slot cut into the rear end ofthe PVC pipe boom for the director elements. The PCB would then be bolted and/orepoxied into the notch.The feed point of the 4-element log-periodic driven section is 50 ohms balanced. Theoriginal design used a quarter-wave sleeve balun, constructed of concentric pieces ofpipe, with an integral female “N” connector at one end. A possible easier-to-fabricatealternative balun would be a piece of coax cable with several ferrite beads, of a mixrated for the VHF/UHF frequency range, slipped over it. One end of the cable wouldhave ring terminals to connect to the feed point; the other would have a cable-mountfemale “N” socket attached, ready to accept a feedline with a normal male “N” plug.WA8LMF04 November 2007
Manual For KLM 27 Element UHF “Bandpass Yagi” Antenna Model KLM-420-470-27 This antenna consists of a 4-element broadband Log-Periodic surrounded by one conventional Yagi reflector and 22 Yagi-style directors. The resulting antenna has continuous coverage with a uniform pattern, SWR and gain across the entire amateur
500324053005 reset ic max811seus t klm-2810 2 500324053006 assp ic ds2411r t&r klm-2810 1 500334002100 inductor nlc453232t-4r7k-pf klm-2810 2 500335400380 crystal cx-49g-24.576mhz klm-2810 1 500335400400 crystal cm200s 32.768khz klm-2810 1 500404001100 inductor blm18bb121sn1d klm-2810 1 500404001280 blm18bb470sn1d klm-2810 2
500324053005 reset ic max811seus t klm-2810 2 500324053006 assp ic ds2411r t&r klm-2810 1 500334002100 inductor nlc453232t-4r7k-pf klm-2810 2 500335400380 crystal cx-49g-24.576mhz klm-2810 1 500335400400 crystal cm200s 32.768khz klm-2810 1 500404001100 inductor blm18bb121sn1d klm-2810 1 500404001280 blm18bb470sn1d klm-2810 2
Quick Start Guide 24. Crossover Type HP/Bandpass - The crossover of channels 3/4 can be selected as a high-pass or bandpass type. For example, bandpass is super for bi-amping your speakers, with channels 1/2 high pass for tweeters, and channels 3/4 bandpass for mid-range. 25. LP Crossover Frequency - Selects the lower frequency of the
Continuous-time filter design considerations -Monolithic highpass filters -Active bandpass filter design Lowpass to bandpass transformation 6:e Emalpx th order bandpass filter Gm-C bandpass filter using simple diff. pair -Various Gm-C filter implementations Performance comparison of various continuous-time filter topologies
computer-aided interdigital bandpass filter design For reproducible customized design in the 0.4-5 GHz frequency range Oneofthe morechallenging difficultiesfacing the Amateur experimenter in UHF and microwave com munications is to construct good bandpass filters a
lAvAliere microPhone, uhF wireless PAssPort systems Lavaliere microphone used with UHF wireless systems for Passport units. This microphone will NOT work with the older VHF belt pack transmitters. Part # Description MSRP 069-9020-000 LAV MIC WRLS UHF EXEC KIT (MU-53L UHF) 99.99 heAdset microPhone, wireless uhF PAssPort systems
Band radio users who use regular UHF frequencies and are not required to move. For example, a public safety UHF user of non-T-Band frequencies works with one of the above-mentioned agencies. Because they are both UHF, the T-Band and the non-T-Band user can communicate. If the T-Band agencies are forced to relocate to a non-UHF band, they will
The American Board of Radiology . ATTN: Valerie P. Jackson, M.D. Executive Director . 5441 E. Williams Circle . Tucson, Arizona 85711-7412 . SUBJECT: AMERICAN BOARD OF RADIOLOGY, REQUEST FOR ADDITIONAL INFORMATION REGARDING RECOGNITION OF NEW BOARD CERTIFICATES AND MODIFICATION OF THE CURRENT . RECOGNITION OF CERTIFICATION IN DIAGNOSTIC RADIOLOGY . Dear Dr. Jackson, I am writing in response to .
