UHF TV antennas for Lectrosonics receivers Srb.

[sergiofucchi]

I have seen some pictures sound of carts that someone uses UHF TV antennas. I would like to know how I have to do to connect two of these to my two Lectrosonics SRb.

 

Sergio.

[VASI]

You mean this?

 

http://www.lectrosonics.com/390-ALP620/View-details.html

[sergiofucchi]

No, as these:

http://www.telecoantenna.com/19/awd22-awd42-awd66-awd90-antenne-uhf-lambda.html

[nwstudios]

I have seen some pictures sound of carts that someone uses UHF TV antennas. I would like to know how I have to do to connect two of these to my two Lectrosonics SRb.

 

Sergio.

TV antennas will most likely come with an F connector.

F to BNC adapters are readily available.

[Jim Gilchrist]

Sergio,

Yagi antennas are often used for radio mic systems when high gain directional antennas are required. 

 

The frequencies most radio mic systems operate in are also used for television broadcasting, so radio mic yagi antennas look very much like yagis used for tv antenna systems. The sharkfin antennas Vasilieos linked to are a type of yagi antenna, they cover a wider bandwidth than the more traditional "tubing on a bigger piece of tubing" form factor generally do, although it's possible to build broadband conventional yagis.

 

A couple of options that are available are shown here and here,  You can read more about them here.

Best regards,

Jim

[chris_bollard]

Yagis can be fairly large, if you are thinking of having them in a bag setup

[iklioze]

I'm using this. Almost $33 in South Korea. But it is only RF type connector because it is for HDTV(470-806MHz) indoor antenna.

So you'll need connector. RF(M)-BNC(F), BNC(F)-SMA(M)

http://spectrum.co.kr/english/main/antanna/lp49.asp?cate=1&cate2=11&cate3=111

[sergiofucchi]

Very interesting, but this has 75 ohm of impedance and Lectro receivers have 50 ohm in antenna. Do you use an adaptor from 75 to 50 ohm?

[iklioze]

No. But it gives me great range. And you can put it in your front pocket of petrol bag(PEGZ-1).

[fieldmixer]

Bargain! Where can we get those in north America?

[iklioze]

Alomost HDTV antenna you can use.

http://en.wikipedia.org/wiki/North_American_broadcast_television_frequencies

 

Because transmitter frequency is in broadcasting HDTV range. 

You can find it PCB type LPDA HDTV antenna with connector. Or you can make it, but DIY is not cheap.

http://www.amazon.com/s/ref=nb_sb_noss_1?url=search-alias%3Delectronics&field-keywords=HDTV+antenna

 

PCB is broken easy, but I don't want to borke my Lectro antenna during RunNGun style shoot. 

If you are using HDTV antenna on location, it looks like you are watching TV.

So I'm put it in front pocket of my petrol bag and please remind that LPDA is directional.

[studiomprd]

" The sharkfin antennas Vasilieos linked to are a type of yagi antenna, they cover a wider bandwidth "

actually the typical sharkfin is a Log Periodic Dipole Array antenna, and Yagi (Actually Yagi-Uda) might be considered a form of LPDA

 

" this has 75 ohm of impedance and Lectro receivers have 50 ohm in antenna. "

if you insist, use the proper coax, and don't worry about it,  I suppose you could locate an appropriate antenna tuner; I used to have one for my mobile ham rig (200 watts PEP output), but now the transceiver  have an automatic tuner included, and the antenna is actually tunable as well

 

if you use a TV antenna, be sure you get one labeled for HD, so you will get the best sound....

[Jim Gilchrist]

" The sharkfin antennas Vasilieos linked to are a type of yagi antenna, they cover a wider bandwidth "

actually the typical sharkfin is a Log Periodic Dipole Array antenna, and Yagi (Actually Yagi-Uda) might be considered a form of LPDA

Thanks, Senator.

I was remembering what my father told me, and he's been dead since 1993. I may have a faulty memory or he might have been wrong but the antennas he designed worked well enough to help make radar work on ships in the '40's and put a man in space and then a couple of them on the Moon in the '60's.

 

He was probably keeping thing simple for a dope like me.

 

The perfboard and buss wire yagis LPDA's he helped me built for fun in the early '80's had crumbled to dust when I stumbled across them in a corner of my shop when packing for the move to our new place in 2011. Made me a little sad.

Best regards,

Jim

[nwstudios]

Very interesting, but this has 75 ohm of impedance and Lectro receivers have 50 ohm in antenna. Do you use an adaptor from 75 to 50 ohm?

 

If you only knew how badly how most broadband antennas actually performed

The impedance mismatch is pretty negligible in the overall scope of things.

The receiver side, where RF is not being reflected back, is much less critical than transmitters.

.

[jerryray]

A couple of things to consider if you choose a UHF TV Antenna.

 

First most are horizontally polorized. Most of the time your transmitters are vertical, but not always.

So you will have to mount the antenna accordingly.

Secondly they are more directional because they have more gain.

If your mics are off to the side you will have more signal loss than a Shark fin antenns because they have less gain.

[sergiofucchi]

For this reason I think to use two antennas placed at least 7 meters from one another.

 

Sergio.