My uhf aerial

Forums › Freeview (DVB-T/DVB-S) › My uhf aerial

qwerty7

434 posts

Ultimate Geek
+1 received by user: 12
Inactive user

Topic # 120963 19-Jun-2013 18:23

This is my uhf aerial. Not The best I know but I want to try and make it work rather than buying a new one.

The rear plates are not attached to any wiring I assume as the rear cage of the spikey type uhf antennas are not, I guess these plates are to reflect the signal onto the smaller plates?

The front plates are connected to the inner wire of the coaxil cable.

Should I connect the rear plates to the outer part of the coaxil cable?

Or should I build some extra plate onto the front and attach them to the outer part of the coaxil cable?

Brunzy

717 posts

Ultimate Geek
+1 received by user: 80

Trusted

Reply # 839729 19-Jun-2013 19:07

Its a PL10 , the balun is in the middle in a box about 3" sq. Connect it to that & your done.

B1GGLZ

1933 posts

Uber Geek
+1 received by user: 130

Reply # 839731 19-Jun-2013 19:12

It's probably not going to work very well as you really need some sort of matching balun.
You are correct that the back part is the reflector and not connected to any co-ax.
If connecting coax directly to the front elements it should be inner to one side and braid to the other side.
However top and bottom elements are joined in parallel in your photo and ideally the connecting strips from bottom to top should cross over i.e top left element to bottom right and vice versa.
Good luck but you'd really be much better off buying a new one which would be complete with proper matching balun and f connector. This should give you the general idea
http://www.dicksmith.co.nz/antennas/uhf-phased-array-tv-antenna-dsnz-l3087
Magnify the picture and you'll see what I mean.

B1GGLZ

1933 posts

Uber Geek
+1 received by user: 130

Reply # 839739 19-Jun-2013 19:18

Brunzy: Its a PL10 , the balun is in the middle in a box about 3" sq. Connect it to that & your done.

You must have good eyes. Looks just like a black mass to me. No obvious balun box.

qwerty7

434 posts

Ultimate Geek
+1 received by user: 12
Inactive user

Reply # 839769 19-Jun-2013 19:48

Sorry should of explained better.
Yes the balun box is there with it, I pulled it apart to clean the connections etc. Inside the box is a simple circuit which is connected as described in the first post. The middle wire of the coaxial cable is connected to the two front plates and that is it. The Ariel works but I cannot get channel 1 or 2

Skolink

1079 posts

Uber Geek
+1 received by user: 31

Reply # 840631 20-Jun-2013 21:36

qwerty7: The Ariel works but I cannot get channel 1 or 2

You mean you can't get any of the TVNZ mux channels? Are the MediaTV (eg TV3) and Kordia (eg Prime) signals only marginal?

qwerty7

434 posts

Ultimate Geek
+1 received by user: 12
Inactive user

Reply # 840643 20-Jun-2013 22:08

Tv 3 and prime signals seem good and I don't experience any rain fade effect. Although I cannot find the part of the menu that shows signal strength. I can rarely get channel 1/2 at all.

qwerty7

434 posts

Ultimate Geek
+1 received by user: 12
Inactive user

Reply # 851303 9-Jul-2013 06:41

I assume this pl10 type aerial is weaker than the spikey type

Jaxson

6751 posts

Uber Geek
+1 received by user: 594

Trusted

Reply # 851315 9-Jul-2013 07:40

It is what it is. If you have cleaned the connections up and orientated it correctly then the next step is a new aerial that actually works.

Brunzy

717 posts

Ultimate Geek
+1 received by user: 80

Trusted

Reply # 851490 9-Jul-2013 12:36

Or put it in the optimum location
It's a few dB weaker than a small yagi

qwerty7

434 posts

Ultimate Geek
+1 received by user: 12
Inactive user

Reply # 851691 9-Jul-2013 16:06

Oh so it sort of helps if you don't have it mounted incorrectly by 180 degrees.

I will see how it holds up in the bad weather

Jaxson

6751 posts

Uber Geek
+1 received by user: 594

Trusted

Reply # 851777 9-Jul-2013 17:48

qwerty7: Oh so it sort of helps if you don't have it mounted incorrectly by 180 degrees.

Technically that won't matter, but 90degrees out and yes, you'll have problems.

Needs to point in the right direction and be orientated to the correct rotation/polarity too.

qwerty7

434 posts

Ultimate Geek
+1 received by user: 12
Inactive user

Reply # 851787 9-Jul-2013 18:06

Jaxson:
qwerty7: Oh so it sort of helps if you don't have it mounted incorrectly by 180 degrees.

Technically that won't matter, but 90degrees out and yes, you'll have problems.

Needs to point in the right direction and be orientated to the correct rotation/polarity too.

As if I could not feel any dumber today, yes I meant 90 degrees.

Brunzy

717 posts

Ultimate Geek
+1 received by user: 80

Trusted

Reply # 851884 9-Jul-2013 19:35

Sorry , but technically it does matter,
all depends on how good the F/b ratio is .
By optimum location ,I mean the physical location ,
if you are shaded from the Tx , you can easily half / double your signal in
a Sq meter, but you need the appropriate equipment to find out where that spot is.