Looking for ideas for a ~25 watt plate modulated homebrew Pissweaker rig

[W3SLK]

Rick, I don't have any links regarding power supplies in and of themselves. I just service the ones connected to our ozone generator. I will say this, it makes power control very easy. The output power of the generator, (KW) is controlled via loop power, (4~20 ma). This is done from our DCS system based on the ozone required. We use these as part of a disinfection train of our DI and ERW water streams. The ozonated water is then run through a string of UV lights that destroys the ozone after disinfection. I was really surprised at the size of the components for the generator though. I would say the PS board is about 8X11.

[W3SLK]

Here this guy did a swiched mode power supply for a Heathkit Warrior Amp. Its only 1500 VDC but you can get the idea. Maybe ask him some questions.
http://w5jgv.com/hv-ps1/

[AG5UM]

Toms original post said "for a 20-35 watt carrier", I was thinking originally of something cool to drive a linear.....
It's funny how in Ham Radio, the only certainty is that no matter how big the shop is..your going to need a bigger Shop!
Your going to need more ,better parts......and....Its going to need more money....
AG5UM

[K1JJ]

That switched HV supply is very interesting, though appears to be a pretty advanced project.  I'll read thru it again and see if it's worth the effort.

I was thinking that maybe another PDM approach would be going for 5KV with 3500V * 1.4   and the 70 uF 10KV cap.   Rather than the higher voltage 4-1000A approach, maybe  a higher current, lower voltage wud be better in the form of  3-500Zs or 4-400As.    I see in the BC PDM version they used just one 3-500Z to modulate a pair of 3-500Zs.   The triode is nice to eliminate the floating screen supply in the RF final but wud need to be neutralized.   I'm considering three or even quad 4-400As in the final modulated by a pair of 3-500Zs (or 4-400As) in PDM wud be cool.  Or some other combo of this to put 2KV on the RF final and 3 KV on the modulator.  Quad 813s in the final PDM'd by a pair is also FB, but I already have two rigs with 813s. No 4-400A rigs right now.

The pic below shows where I am at right now.  This is how I get a feel for what I wanna do by lining up the tubes, picking them up and sleeping on it.  Each day it's a different dream lineup of tubes until I settle in on one...

Under consideration are 3-500Zs, 4-400As, 813s, 4-1000As and 833As... all in stock.   A 4D32 is not in the consideration group due to its lower 600V plate spec.  That 4X1 sure is a monster for a glass tube.

T

[w8khk]

Here this guy did a swiched mode power supply for a Heathkit Warrior Amp. Its only 1500 VDC but you can get the idea. Maybe ask him some questions.
http://w5jgv.com/hv-ps1/

Thanks for the leads.  He does have an interesting website.  I will peruse and digest the information before contacting him.

[K1JJ]

Rick,

Thanks for the detailed info on the previous page about power supplies, etc.  It took some time to digest.  The jury is still out here.

On a different subject, I'm looking into possibly using an external anode tube also, like your 3CX-2500F3 ideas for series modulation.  The air noise is what keeps me concerned.  How are you making out with your noise reduction experiments to reduce the air sound?   Could you explain more how to pull this off in a simple manner using fabricated common materials?  That wud be a nice feature - to run a big rig in the shack with muted blower noise.

T

[Opcom]

someone new coming along and idly checking the end (these pages) of this topic looking to see how AM guys do a pissweak 25W rig are going to see that AM folks really mean business.     

[K1JJ]

This thread has moved over to a new thread and topic about building a new KW AM  PDM transmitter:


http://amfone.net/Amforum/index.php/topic,46420.msg332358.html#msg332358