any amount of misplacement, near any material, of 300 ohm will have signal loss. you are less likely to have that misplacement in 7 feet.
Yes, but there is also an advantage to that, because then you can use the old aluminum foil sliding trick to tune the 300 ohm wire.

Yes, but there is also an advantage to that, because then you can use the old aluminum foil sliding trick to tune the 300 ohm wire.

Is that anything like the Toroid Ring trick for antenna matching?

I'll give the 300 ohm wire to the Matching Balun a try first.
Since I have several short pieces of 300 ohm wire laying around any way. ;)


Signed: Janitor Tzap

Ive never used the regular Amazing Goop, I used the Plumbers Goop. So you may want to do a test piece and measure, if any, the resistance with an ohmmeter on the highest range when its dry.
It says Plumbing on the tube. Says it hardens by solvent evaporation and forms an immediate bond. It is a contact adhesive and sealant. Yea, I better test on an old balun I have!

Thanks 300ohm.

Thanks for the Picture 300ohm.

Where do you think I could find one or two?

Thanks,

Intravino

Flea markets.

Back to the balun loss topic:

I just finished bending the 6 ga copper leads for my SBGH and decided to test the two baluns I bought from Raybel in Montreal. Using only the zigzags, no refector, in a concrete basement with no LOS, I could view channel 21 at 76 % with the first and at 97-98 % with the second. Wow !

Guess I'll stick with the 2nd one.

Thanks again 300ohm for the plans and tests.

I could view channel 21 at 76 % with the first and at 97-98 % with the second. Wow !

Heh. Same brand too ?

300ohm,
Should baluns be polarized? The one I bought shows continuity between the wires.

And, as far as a bowtie, do the phaselines have a certain polarity?

Should baluns be polarized?
Well, I have heard that sometimes reversing the connections on the balun improves reception.

Well, I have heard that sometimes reversing the connections on the balun improves reception.

The reversing of the baluns which type of balun would this be , one that has no impedence between the 75 ohm out to the 300 ohm in , or the ones with a small resistence from 75 to 300 ?

I think i worded it correctly , what I'm asking is if you took a meter and checked for some resistence from input to output.

300ohm: yes, same brand !!! Worth testing, no ?

Bonjo, can you post a picture of the balun?

I also bought two baluns from Raybel a while ago, they cost about $5 each, noname on it. The wires are freehanging, not of the 300-ohm twinlead. The balun was made for exterior use with a rubber sleeve for protection

is that the one you are testing?

I had a one that was not working like the other. I looked inside and move the wires (almost touching) so the space was equal to the space on the coax connector, and now is as good as the other. It's hard to get good performance when the pay is $0.35 per hr.

hungt1999: I will post a pic ASAP

Well, I have heard that sometimes reversing the connections on the balun improves reception.
I don't see how it would make a difference...the one I have is showing continuity, between the leads, center conductor and shield...everywhere. Both are showing the same. I could understand some resistance, but this is a dead short.

Someone please explain this to me.

300ohm: yes, same brand !!! Worth testing, no ?
Heh, it just goes to show each one can be different.

don't see how it would make a difference...
Yeah, not much logic to it. But if it works for you .......... ??

As I went to take pictures of the balun, I decided to redo the test.
In order to minimize errors, I tried different locations and, while doing that I noticed that holding a connected balun in my hand gave the highest signal read.

I re-did it a few times and guess what ? Both baluns peaked at 85 %

Baluns alone, no antenna...

In my opinion, this shows that it is worth testing the antenna and its connections before putting it on the roof.

Sorry about my hasty conclusion. Guess I could not wait trying the leads ...

http://www.digitalhome.ca/forum/picture.php?albumid=136&pictureid=640http://www.digitalhome.ca/forum/picture.php?albumid=136&pictureid=641

Yeah, not much logic to it. But if it works for you .......... ??

Do all baluns check this way? I mean continuity between the leads. I was thinking something was wrong with the ones I have.

Bonjopj, thanks for the picture. That is exactly the balun I bought for $5 each from Raybel

I tested that balun on one of my VHF13 yagi and found that the position of the wires is so sensitive. In my case while I was trying to catch WVNY-DT, a slight movement of the spacing and relative position of the wire significantly affected reception so I ended up using a cheap 99 cents balun that had a constant spacing of the 300ohm wires

hungt1999: my pleasure.
Grand Audio: Thanks for your comment, I will solder the balun leads to the copper elements. And test again...