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
