there is much confusion and myth surrounding the humble bird 43,
many people claim birds ignore signals that fall outside the rated frequency range including the harmonics of hf signals,
i will have one last go at clearing this nonesense up but i doubt it will change many minds,
this is NOT TRUE, it is a cb myth invented by a retard, the myth has been banded around cb forums for so long the line between truth and fantasy has become obscured, why people take what others tell them as gospel without doing their own tests is beyond me but hey thats cbradio for ya,
a while back freecell came up with the notion of harmonic oversampling based on the idea that as you move up in frequency the line section length becomes a larger percentage of the wavelength of the test frequency and as such will oversample frequencies that are higher than the rated frequency range of the meter, the claim is that the meters will sum all these sampled readings together giving a higher reading than what is really there,
he suggested a simple test of measuring known vhf/uhf signals to confirm this idea,
how many people have actually done any testing?, very few i would presume from what i read on cb forums,
freecells claims made sense to me so i did the tests with more than one radio and several meters of differing quality and type of line section, i used a good quality dc-2ghz 50ohm dummyload not some homebrew or mfj/palstar pos, i connect the meters straight to the load with no jumper,
my bird43 with hf slugs DOES NOT oversample nor does it ignore signals above 30mhz,
signals on 50mhz 70mhz 144mhz 440mhz all read much lower than the actual power applied,
from memory a 10w signal @144mhz reads about 2w on the bird using a 10w hf slug,
when using a vhf slug the bird reads very close to the tellewave and welz sp600,
on some of my meters mainly the stripline coupler cb type meters i do see significant oversampling as freecell claimed,
from what i see with the bird hf slugs i presume they have some form of frequency tailoring that attenuates vhf and above signals within the slug, maybe a shunt capacitor,
the bird certainly responds less to high frequency signals than my other meters including the ones using wideband torroidal couplers,
since i do not have any means to add a measured amount of harmonic content along with a clean hf signal and observe how each meter responds i cant say how any of them are effected when measuring amplifiers or clipped radios with high harmonic content,
i believe they will all show more power than is actually on frequency if high harmonic content is present and the bird43 using hf slugs would likely be less effected than many other meters going by what i see in my simple tests but i cant prove it,
what i can prove is that anybody telling you the bird43 using hf slugs do not see signals above 30mhz is talking the same kind of cb bullshit that ampower spouts to his retarded followers, they do not have a majical filter that cuts off sharp at 30mhz, the response of bird hf slugs rolls off as frequency increases above design frequency,
some meters do increase sampling as frequency increases above design frequency,
the bird also acts different to my other meters when measuring amplitude modulated signals ( not what its designed for ),
on some radios i can see forward swing, swap the meter to the bird43 and i see little forward or even backwards swing, my other meters do not do that, i dont know why that is but thats what it shows,
dont take my word for it go do your own tests, use a quality wideband dummyload, report your findings.
many people claim birds ignore signals that fall outside the rated frequency range including the harmonics of hf signals,
i will have one last go at clearing this nonesense up but i doubt it will change many minds,
this is NOT TRUE, it is a cb myth invented by a retard, the myth has been banded around cb forums for so long the line between truth and fantasy has become obscured, why people take what others tell them as gospel without doing their own tests is beyond me but hey thats cbradio for ya,
a while back freecell came up with the notion of harmonic oversampling based on the idea that as you move up in frequency the line section length becomes a larger percentage of the wavelength of the test frequency and as such will oversample frequencies that are higher than the rated frequency range of the meter, the claim is that the meters will sum all these sampled readings together giving a higher reading than what is really there,
he suggested a simple test of measuring known vhf/uhf signals to confirm this idea,
how many people have actually done any testing?, very few i would presume from what i read on cb forums,
freecells claims made sense to me so i did the tests with more than one radio and several meters of differing quality and type of line section, i used a good quality dc-2ghz 50ohm dummyload not some homebrew or mfj/palstar pos, i connect the meters straight to the load with no jumper,
my bird43 with hf slugs DOES NOT oversample nor does it ignore signals above 30mhz,
signals on 50mhz 70mhz 144mhz 440mhz all read much lower than the actual power applied,
from memory a 10w signal @144mhz reads about 2w on the bird using a 10w hf slug,
when using a vhf slug the bird reads very close to the tellewave and welz sp600,
on some of my meters mainly the stripline coupler cb type meters i do see significant oversampling as freecell claimed,
from what i see with the bird hf slugs i presume they have some form of frequency tailoring that attenuates vhf and above signals within the slug, maybe a shunt capacitor,
the bird certainly responds less to high frequency signals than my other meters including the ones using wideband torroidal couplers,
since i do not have any means to add a measured amount of harmonic content along with a clean hf signal and observe how each meter responds i cant say how any of them are effected when measuring amplifiers or clipped radios with high harmonic content,
i believe they will all show more power than is actually on frequency if high harmonic content is present and the bird43 using hf slugs would likely be less effected than many other meters going by what i see in my simple tests but i cant prove it,
what i can prove is that anybody telling you the bird43 using hf slugs do not see signals above 30mhz is talking the same kind of cb bullshit that ampower spouts to his retarded followers, they do not have a majical filter that cuts off sharp at 30mhz, the response of bird hf slugs rolls off as frequency increases above design frequency,
some meters do increase sampling as frequency increases above design frequency,
the bird also acts different to my other meters when measuring amplitude modulated signals ( not what its designed for ),
on some radios i can see forward swing, swap the meter to the bird43 and i see little forward or even backwards swing, my other meters do not do that, i dont know why that is but thats what it shows,
dont take my word for it go do your own tests, use a quality wideband dummyload, report your findings.