<3-500s may still be in production but the cost is high compared to <years ago and quality may be questionable. <Good tubes in ham service should last for decades. There are SB220s <out there with th
Never heard of an ICAS rating for the 3-500. I have a dual 3-500 amplifier with a pair of 20 year old RF Parts 3-500s and they're still at full output, but they have been run conservatively especiall
What is the current (pun intended) max grid current for a pair of 3-500Z's now days? And does it matter what the Plate voltage is? Joe WB9SBD 73 Rob K5UJ _____________________________________________
For actual Eimac tubes the Eima DATA sheet shows much greater efficiency and usable power with 4000 volts on the plates. Henry made several amps with a 3200 or 4000- volt switch and the 3KA I had eas
I had an AL80A for which I built a 4000 V power supply. The output network needed a fair bit of change on the low bands because the load point changed, but it would easily make 1200 W out on 40 m (th
Author: gudguyham--- via Amps <amps@contesting.com>
Date: Thu, 8 Oct 2020 16:01:27 +0000 (UTC)
3-500 tubes with directly heated cathodes, unlike tubes like 8877 and 3cx800s etc do not have fragile grids nor does reasonable peak grid current have cumulative degrading effects on the grid. Becau
It depends on the plate voltage. You have to look at the Eimac data sheet to make a determination. As far as I know, the Eimac Data sheet is the standard the industry looks at when designing an ampli
Where are you looking? At the characteristic curves? There's nothing for 4KV in typical operation; just max ratings. 73 Rob K5UJ _______________________________________________ Amps mailing list Amps
If that's for a single tube, that's way too high. 73 Rob K5UJ _______________________________________________ Amps mailing list Amps@contesting.com http://lists.contesting.com/mailman/listinfo/amps
I'm thinking 3500/3600 plate voltage or so Joe WB9SBD Sig The Original Rolling Ball Clock Idle Tyme Idle-Tyme.com http://www.idle-tyme.com On 10/8/2020 1:05 PM, Rob Atkinson wrote: On Thu, Oct 8, 202
You can go ahead and beat on a single 3-500 like that every day and I guarantee you'll be getting a new one in around 5 years. Especially if you operate high duty cycle or with a lot of compression.
I think as long as the max grid *dissipation* isnt exceeded, the grid *current* is at best an about here guide. But what I couldnt determine is, given the grid current, whats the dissipation? Is ther