"Debunking Technical Myth and Hype" The information provided on this page is intended to inform you, the consumer, by supplying the necessary technical information required to make sound purchasing decisions while at the same time saving your hard earned dollars from being spent foolishly! In a service/retail industry where most of us strive to be the very best at what we do, some of us have a tendency to let our personal zeal and greed relieve us of our intelligence, as well as our common sense! This link has been created in an effort to restore some modicum of sanity in a world where grandiose claims and technical hoopla seem to be the rule of the day! I also welcome my fellow technicians to provide their input as well, since my intent here is not to slander or malign others who are engaged in plying their own trade, but to establish some realistic guidelines and provide technical specifications for some of the equipment currently available in the market today... The sample in the immediate lower left was brought to my attention by a customer who was looking to purchase an amplifier but had indicated to me that he was somewhat leary about the figures quoted on this particuliar web site because they were considerably higher than what he had seen elsewhere! _____________________________________________________________________________ model stock turbo = 1# exceeding rated input drive levels 250HDV 2# increasing operating voltages 250 350-400 *350HDV *350 *450-500 *sorry folks....but the devices used in 400V these amplifiers are simply not 400 capable of producing these "claimed" 550-600 power levels......... 500R 500 750-800 Device = 2SC2879 667V PEP Out = 100 W. 650 Gp Gain = 13 db. 800-900 Vcc = 12.5 VDC Drive/Input = 5.0 W. Watts PEP IMD3 = -24db. _____________________________________________________________________________ * The 350HDV utilizes 2 Toshiba 2SC2879 Transistors Typical output levels for this unit are as follows: AM....+/- 200 W.__________________SSB....+/- 300 W. Attempts to exceed drive level input or increase supply voltages above +/- 14.0 V will result in IMD, parasitic oscillation and shortened life of the equipment! All dependability/reliability is lost. Sound engineering principles tells us that the "extra" PWR. watts alluded to in the figures at the top of the page is meaningless when you realize that, (using a ref. of 200AM/300SSB) to produce a noticeable increase in signal level one would have to double these figures to 400AM/600SSB to yield ONLY a 3db increase in signal strength at the received end, which amounts to 1/2 an S-Unit, perceived as definitely noticeable to the human ear! Note: 6 db = 1 S Unit........ note: see the Transistor DataBase in the side menu on the main page for transistor specification data sheets in pdf format. ----------------------------------------------------------------------------- The Antron 99 is not a half wave antenna! (Another myth destroyed) You saw it, you looked at it, it was about 18 feet long, and right off the bat you decided, "It's a half wave antenna".......Well, you're wrong again! The Antron 99 is a loaded 1/2 wave over a loaded 1/4 wave, variable mutual transductance tuned vertical antenna! "Anyone who had read the advertising would know this"! here is a link to the equivalent electrical schematic representation of the A99. http://www.firecommunications.com/images/a99schem.gif how anyone can look at this and call it a shunt-fed 1/2 wave defies reason. here are the patent files for the A99 http://www.firecommunications.com/patents/antron99/ The term colinear simply means "in a straight line". Any antenna using 2 or more discrete elements stacked one above the other, is a colinear array. To be exact, it is a 2 element stacked colinear array for the 10 and 11 meter bands! Put it together and place the feedpoint at 37 feet above the ground, (which is approximately one wavelength at 27 mhz) and don't forget to connect the other end of the feed to the "base". Pick up the ground plane kit for it later on as this is a worthwhile addition! Besides decoupling the antenna from the feedline and optimizing the input impedance the ground plane kit will also help further reduce rf interference and TVI in the near field of the antenna.