aurel

Hi Admin and others ! As i said in PM i have question. I have one old broken TV UHF yagi-corner antenna , and what is left from antenna is 5 directors are OK . - bowtie shaped half of feed Point dipole bowtie shaped aluminum pipe as element holder with original holes. I don't have reflector.. this is how original looks:

wow Juri is a tuff guy it looks that he like to simulate antennas it looks to me like he is fake expert but some of simulations looking nice

Thank you very much for simulation !! But i don't understand what kind of dipol is that ???? looks like -E shape ??? what is that? I have mateials for 5 directors bowtie shape and for one bowtie "dipole" so probably results should be little bit better maybe 12dB gain anyway even on your way i think that should work. currently i cannot mount antenna on foof because of very bad weather here.

I dont know because i dont have it...

It is suppose to be standard UHF antenna for 21-69 chanels so i think from 470-860Mhz ..right?

ahh sorry missing dim is 63 mm

ahh i see ...shape is little bit tricky..right i do my best with small plastic measuring triangle and here is . For testing i will put it again on old holder to try it as yagi ...

of course quick measuring from image

Ok I mut explain why I ask.. as far as i remember when i use this type of antenna ii don't get solid results then i become pissed off and cut aluminum thin and build yagi with 15 directors using folded dipol shape for all directors and of course with proper reflector and all that time this antenna work excellent.

Do you mean like this:

I am not sure that i understand your answer. Do you mean something like panel antenna with bowtie elements instead of rebuild this small yagi?

On the image ..is ordinary folded dipole as active element but i have on this one ith same shape as directors. so my questions should be : 1 . can i use or made something else (aluminum wire mesh ) or another bowtie shape as Reflector? 2. because i have only one side of active element ...is it better to build another one bowtie shaped or to build one like is on image above? thanks...

OK i have original - fabric made - asimetric element .hence baloon and i add it to antenna and now seems that work better. This small mink fractal i already build for 2,4ghz and work well but maybe minkowski shape is not the best for biquad type

This one is little bit different type of minkowski fractal i saw it before . anyway antenna is tested ..from 14 DVB TV chanels in my area i can pick them all. Two of them are not stable hence weak signal or just different direction. I must say that i pick up those TV channels without reflector...but when i add reflector then i get more stability as it supposed to be ... also antenna for testing is on TV set with just 1 m of coax 75ohm cable.. so i will mount it on my roof to test antenna outdoor. all best..

I don't know ..i just follow the logic ..and most of fractal antennas are created like this. Are you sure that CST know calculate fractals ?

And yes it is lambda / 4

he he ... what is NOT TRUE... 15x20 ? yes it is 300....but maybe some other aspects are not true i don't know?

standard UHF chanels 21-69 freq 470 -860 Mhz well 15mm x 20 sides is 300mm

It is late here ..so i will trying tomorrow ... I already build one similar and give to my friend ..he says that work fine as indoor antenna.

ok then which sizes to use ?

In general ...can we use this dimensions (from colinear antenna) to build this one? 27mm, 6mm, 27mm, like is on picture?

Can we use this shape for 2.4ghz? I first time see such a design !!! with what dimensions?

Yes i know i will fix that...

Hi How to connect 4 zigZag elements i have crazy idea! Is there image of feed point conections for alredy made 4 zigzag with 4 elements ? thanks

ok they are here ,,quality is bad and those are just prototypes...he he one is yagi biquad and second is jensky when i change cable both work fine ...it looks that jensky work better because yagi reqiure more directivity