Howdy all...I am looking at constructing 2 W2DU bead baluns as described in ARRL Antenna book that uses 12 Amidon FB-77-1024 beads. Is there a good source to get these at a reasonable price or maybe
Dave: I use CWS Bytemark (http://www.bytemark.com/index.htm) I just received 12 beads SB-1024-77 from them. I think they were $1.50 each. 73's Jim N9WW James E. Chaggaris President PowerOne Corp. 102
From: "R. David Eagle" <kb8nnu@yahoo.com> Subject: [TowerTalk] W2DU Balun Bead Source Howdy all...I am looking at constructing 2 W2DU bead baluns as described in ARRL Antenna book that uses 12 Amidon
There is a good discussion of baluns in the current issue of QST written by Ward Silver. The bead balun is a good choice. 73, Keith NM5G Not trying to change your mind, but you get more balun for the
I tried a Ferrite not long ago and took it off. I had a relatively small donut piece of ferrite and placed it over the coax, I didn't wrap it or anything, just a quick test. Hoping to get rid of any
I've been considering making a balun (1:1) out of a FT-240-43 and RG-142 (or RG-58??), but haven't seen any real conclusive eveidence on their effectiveness. So maybe someone can share their knowledg
That should work pretty well but I would recommend RG-400 teflon for the coax. -- 73, Cecil, w5dxp.com _________________________________________________________________ Your Hotmail address already
VERY good advice. As it turns out, I'm about 90% done with a tutorial on RFI and ferrites that includes a discussion of baluns, a lot of measured data, and specific advice on troubleshooting RFI and
I have used the W2DU chokes and at 1500 watts they get way too warm. I suggest the W0IYH design. I use one at the output of the amplifier and one at the feed point of every antenna. They work GREAT.
This is a problem with ferrite baluns if the choking impedance is too LOW. Maybe you had amps of RF current flowing on that coax, and you put a one ohm impedance in series with it. It's not enough t
The #77 material used for w2du chokes is primarily resistive and thus dissipates power. Other materials are primarily reactive and not as lossy as #77. -- 73, Cecil, w5dxp.com ______________________
Here's some good information on toroidal ferrite materials. Apparently, the FT-240-K has been optimized for baluns. http://www.amidoncorp.com/aai_ferritecores.htm -- 73, Cecil, w5dxp.com ___________
Well I guess if no one else is going to say it, I will. The reason your balun got hot is because you put in in series with your signal not in series with common mode currents. You can't put a balun o
I don't remember if it was on this reflector or another, but the common mode chokes were discussed in great detail with great info from this site: http://www.yccc.org/Articles/W1HIS/CommonModeChokesW
Wow, I missed that. Jerry, you probably should change your "can't do that" statement to a "you'll be sorry if you do" statement. :-) A T-antenna turns the coax into a radiating element. One will cer
Jerry, You get the "observant TowerTalker" award. Feeling dumb, Dan _______________________________________________ _______________________________________________ TowerTalk mailing list TowerTalk@co
Ok well that makes sense, since it did get (and I mean extremely hot) so I made a mini heater for the shack. Probably a good thing I took it off :0) So the ferrite was in series with the signal path.
Although it may not be readily apparent, if you short the inner connector to the outer connector on a piece of coax, zero RF current flows on the inner conductor. All the RF current flows on the out