Agreed on #73 ferrites for MW. Also the BOG xfmr I made has thicker than extremely flimsy wire and is lots harder to break than a couple of the xfmr's I have obtained over the years. Slowly I am learning how to make my own stuff..... 73 KAZ (5 thumbs on each hand)
-----Original Message----- >From: Chuck Hutton <[email protected]> >Sent: Sep 7, 2010 8:41 PM >To: [email protected] >Subject: Re: [IRCA] Beverage antenna kit > > >This doesn't look good. He's not using the cores that are best for MW, and his >idea of using iron powder cores with 10 - 40 permeability would require >hundreds of turns of wire on the biggest cores available. There's no reason to >do that - he could use #73 ferrite cores and have a better transformer that is >easier to make. > >His termination resistors would work fine until the day that there is a nearby >flash of lightning. See http://www.w8ji.com/beverages.htm and scroll down to >"Why Composition Types?" for an explanation. For a DXpedition they would be >fine but for a permanent installation, I would not use them. > > >Chuck > >> Date: Tue, 7 Sep 2010 04:34:33 +0000 >> From: [email protected] >> To: [email protected] >> Subject: Re: [IRCA] Beverage antenna kit >> >> Thanks, Chuck for bringing the technical issues to the forefront. I emailed >> the fellow directly, and here's his reply: >> >> Dear canswl, >> >> Good evening Gentleman ! >> I am using binocular ferrite cores for my >> transformers. The material I use closed to 43 >> material . It has permeability of 850 .That >> permits me to bild matching trasformers to >> frequencys 1.7 to 27 MHz. My goal is - to let my >> customers experiment on a different bands .... >> For MW I would use iron powder toroids with >> permeability of 10-40 ...I have such toroids but >> was using them only for 160 meters applications >> and stoped to do that ... >> Termination resistors I use are metal film >> resisotrs . After long experiments I use russian 2 >> watt MLT-2 resistors . These resisotrs has 5 times >> overload ability and has very small reactive >> resistance in values range untill 500 OHm - due to >> their specific construction .. >> I have adjustable termination resistors as well . >> We just moved to Canada and retuning to the >> business step-by-step . 4 BV antenna remote >> switches , bi-derectional BV , EMI coax arrestors >> , SDR receivers ,preamplfiers and other Low Band >> DX-ing gear will be available on eBay very soon >> ... >> You can try it . I sold my gear to almost 40 >> countries ... It's just works . >> Regards ! Alex >> >> - kafa2500 >> >> Looks like he's very accommodating for our needs. Being so close, I might >> just have to pay him a visit sometime and see his line up! ......Walt >> >> >> ----- Original Message ----- >> From: Patrick Griffith <[email protected]> >> Date: Monday, September 6, 2010 18:40 >> Subject: Re: [IRCA] Beverage antenna kit >> To: IRCA <[email protected]> >> >> > >> > Very good points Chuck. I have no experience at all with the >> > Beverage antenna. I have never lived in a place where I could >> > erect one. I just noticed this kit on e-bay and thought I'd >> > point it out. >> > >> > > From: [email protected] >> > > To: [email protected] >> > > Date: Mon, 6 Sep 2010 17:57:31 +0000 >> > > Subject: Re: [IRCA] Beverage antenna kit >> > > >> > > What I would ask this fellow is what ferrite material he used. >> > Hams tend to use cores good from 2 - 30 MHZ and they don't work >> > too well when used for LW and most of MW. A popular ham core is >> > Amidon type 43, and it certainly is not optimum for LW. >> > > >> > > And if I am going to pay someone to provide me with a mounted, >> > enclosed termination resistor I would want to know it is a >> > carbon composition type, rather than the extremely more >> > prevalent carbon film resistor which can't take any kind of >> > energy from a lightning discharge. >> > > >> > > Maybe his stuff is recommendable for us, and maybe not. >> > > >> > > >> > >> _______________________________________________ >> IRCA mailing list >> [email protected] >> http://montreal.kotalampi.com/mailman/listinfo/irca >> >> Opinions expressed in messages on this mailing list are those of the >> original contributors and do not necessarily reflect the opinion of the >> IRCA, its editors, publishing staff, or officers >> >> For more information: http://www.ircaonline.org >> >> To Post a message: [email protected] >> > >_______________________________________________ >IRCA mailing list >[email protected] >http://montreal.kotalampi.com/mailman/listinfo/irca > >Opinions expressed in messages on this mailing list are those of the original >contributors and do not necessarily reflect the opinion of the IRCA, its >editors, publishing staff, or officers > >For more information: http://www.ircaonline.org > >To Post a message: [email protected] > _______________________________________________ IRCA mailing list [email protected] http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: [email protected]
