$400
Dave, W3ST Secretary to the Collins Radio Association Publisher of the Collins Journal www.collinsra.com ----- Original Message ----- From: "Jim Isbell" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Saturday, November 22, 2003 3:46 PM Subject: Re: [AMRadio] RF Chokes > What do the cost? I am interested. > > David Knepper wrote: > > >Anyone interested in several large BW butterfly capacitors with a full set > >of KW swinging link coils? > > > > > >Dave, W3ST > >Secretary to the Collins Radio Association > >Publisher of the Collins Journal > >www.collinsra.com > >----- Original Message ----- > >From: "John Coleman, ARS WA5BXO" <[EMAIL PROTECTED]> > >To: <[email protected]> > >Sent: Saturday, November 22, 2003 12:15 PM > >Subject: RE: [AMRadio] RF Chokes > > > > > > > > > >>Hey Jeff, why don't you build a linear grounded grid out of a pair or > >>all three 450s? > >>1. You would have the plate dissipation capability. > >>2. No high level modulator required. > >>3. Pi Net output. > >>4. No need to neutralize on the lower frequency HF bands. > >>5. Same filament source required as with class C and plate Modulator. > >>6. Full output beyond the legal limit. > >>6. Easy Solid State Biasing. > >>7. One HV supply. > >>8. Less distortion. > >>9. Less TVI. > >>10. No arcing when over modulated! > >>11. Smaller foot print (the amp, not you) > >>12. Good on all modes. > >> > >> > >>Disadvantages > >>1. Due to high filament current you will probably have to wind your own > >>filament RF choke of # 6 wire or bigger. > >> > >> > >> > >>-----Original Message----- > >>From: [EMAIL PROTECTED] > >>[mailto:[EMAIL PROTECTED] On Behalf Of Geoff/W5OMR > >>Sent: Saturday, November 22, 2003 9:55 AM > >>To: [email protected] > >>Subject: [AMRadio] RF Chokes > >> > >>A while back, some ham came over, and we got to talking about > >>homebrewing. > >>He was building something, and needed an RF choke. I had a brand new, > >>never > >>used, National RF choke, still in the original box. At the time I never > >>had > >>any plans of building anything. I have my push-pull, link-coupled 250TH > >> > >>final, and even though it was built in the 50's, it will probably > >>outlive me. > >> > >>But, recently I got the urge to build. I think the conversation here > >>about > >>all the homebrewing that's been going on had a heavy hand to spark that > >>interest. I thank y'all for that. > >> > >>The plan is to build up a final, using a single tube in the final. > >>Either a > >>450TL, or a 304TL. I'm leaning towards the 450TL, because I've got > >>three of them, and a single tube, modulated by a pair interests me. > >> > >>I've got the main tuning capacitor (B&W Butterfly w/neutralization caps > >>on the back) an HDVL jack-bar, all the plug in coils for 80 thru 10, an > >>aluminum chassis to mount it on, and most of the necessary associated > >>hardware... except for the RF choke. > >> > >>I found a couple on E-bay... but $8.oo to $10.oo? Are they really that > >>expensive, even still today? > >> > >>Does anyone have a spare they wouldn't mind parting with? > >> > >>73 = Best Regards, > >>-Geoff/W5OMR > >> > >>_______________________________________________ > >>AMRadio mailing list > >>[email protected] > >>http://mailman.qth.net/mailman/listinfo/amradio > >> > >> > >> > >>_______________________________________________ > >>AMRadio mailing list > >>[email protected] > >>http://mailman.qth.net/mailman/listinfo/amradio > >> > >> > > > >_______________________________________________ > >AMRadio mailing list > >[email protected] > >http://mailman.qth.net/mailman/listinfo/amradio > > > > > > > > > _______________________________________________ > AMRadio mailing list > [email protected] > http://mailman.qth.net/mailman/listinfo/amradio
