On 12/4/06, A.R.S. - W5AMI <[EMAIL PROTECTED]> wrote:
I need to post a want on amfone.net. I'm not in any hurry, but sure would be nice to secure one. Thanks Geoff.
If you've got 'em (and they're -much- easier and cheaper to find) you can string smaller inductance values together in series to get the inductance you need. that's what I'm doing, now. See, if I run 1500v @ 300mA, then that's not only 450W DC input to the final, it also presents a Z in the final of 5000 ohms. Currently (till I get my HV B+ supply built) I'm controlling the output carrier with the swinging link. That's all well and good, but the B+ doesn't change, and when you pull the link out to reduce power output (I do it because of the neighbors... self-imposed 'quiet-time, kinda) but when the link is puled out, and I'm drawing 100mA @ 1500v, that makes for around 150w DC input, but the Z has now shot up to 15k ohms of Z. Rule of thumb, as it's been stated here and on the AM Window is 8Hy per 1000 ohms of Z in the final. Well, 8 * 5 = 40Hy. That's easy enough to come up with. 8 * 15 = 120Hy and now we're talking *serious* iron, but I'm doing it. That big chunk of PEter Dahl iron I got from Brett put me just over the 120Hy edge, but that's with 6 chokes in series. When the power supply is built, the B+ will be varied with a VariAC on the primary. At the half-points (750V @ 150mA) = 112.5w DC input - good enough for the neighbors, and the Z stays the same, as if it was 1500v @ 300mA. Therefore, the 40Hy will be all I need. AT THAT TIME, I could probably come up with a 20Hy @ 500mA to help you along the path. but your gonna have to come down here to get it. Shipping is gonna kill ya ;-) -- Operating your AM rig without a scope is like driving our car at night without headlights.(~K4KYV) 73 = Best Regards -Geoff/W5OMR ______________________________________________________________ AMRadio mailing list List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:[email protected]
