1500W RF generator schematic

[Opcom]

This Materials Research Corp. model S-3013 RF generator unit makes 1500W easily and was used for RF plasma generation and sputtering continuous duty application in a wafer fab. It has a 50 ohm output and variable power by screen modulation of the driver. I suppose it would be considered a transmitter. Crystal controlled on 13.5Mhz. Maybe it could be modified for the 14MHz ham band.

Has anyone ever converted something like this?

The 3-ph power supply a bridge rectifier and no filter, but with a small filter, any ripple might be dispensed with. It might also be operable from single phase 220/240V as the open frame 3200VAC HV transformer is 78 LBS and looks like it would easily provide enough power. Just something to look at anyway. There is not really enough room to make it full-bandswitching, but the power is there and conservatively rated. I have 3 of these things.. Good for Parts? The file is too large to post, here is the URL for an 11x17 schematic:
http://www.bunkerofdoom.com/MRC_S-3013.pdf

[Ralph W3GL]

Hey, those beasts have 3-1000A's, grounded grid finals in them!

Strip all the 5763 and buffer junk along with all the other crap in there (good parts!) and then you should have room for a conventional single phase PS.  Leave the final compartment alone till the last of the control, etc stuff is removed. The filament xformer looks to be single phase as is so that is covered. Looks like lots of  good parts in there for the taking, RF as well as control stuff.

That thing should be in a big roll around case so there should be plenty of space to build it into a beautiful 3x1 amp... I think you just might be able to get HV from that 3 phase iron on single phase with the right hookup...

[n2bc]

I converted a PlasmaTherm 2KW, uses a 5CX1500.  The RF chassis layout was also very tight.  The blower was mounted on the RF deck hogging much room, I hung it on the bottom cover of the RF deck - there was plenty of room below it in the original cabinet.  This made it a bit difficult to work on the RF stuff so I temporarily mounted a couple heavy duty angle brackets on the back of the rack & can place the RF deck 'outboard' to access things while still having the deck hooked up and cooled.

The PlasmaTherm was also very light on B+ filtering, only 4uF as I recall. I picked up a Russian cap, 45uF @ 5KV on eBay quite reasonable.

I picked up plenty of space under the RF chassis by eliminating the oscillator & driver (a 6146 stage), plenty of room to mount a vac variable loading cap and the 5CX1500 input circuits.

I didn't have to fuss with 3-phase AC which made the power supply quite straight forward. 

Hope this gives you some ideas.

73, Bill  N2BC

[NE1S]

I got a bunch of those generators, plus a pair of their bigger brother, the 3KW ones using a 3CX3000A7, several years ago. I work in the semiconductor industry and our factory was obsoleting the equipment, and had a warehouse sale. I made sure all the generators got into the hands of hams in the area that would do something with them

I never converted them, mainly because the cabinet was bug and bulky. But I did use the final tubes, sockets, filament transformers, filament chokes, and a few other parts to built a pair of grounded-grid linear amps - one with a 3-1000Z, and one with a 3CX3000A7, on new chassis. A friend built an amp with 3 parallel 3-1000Zs from three of the 1.5KW generators. Same guy used one of the 3-phase plate xfmrs on single-phase using only 2 of the three sets of windings and was perfectly happy doing that.

I still have some of these kicking around if any body needs parts, but the final and IPA tubes have either all been pressed in to service, or I'm hanging onto them for spares for my two amps.

73,
-Larry/NE1S

[W3FJJ]

It looks like that rig will tune right up on 20 meters, just feed
ricebox or other exciter into cathode of 3-1000, ie disconnect 4-125 driver.

I recently converted a Henry 2000d, 3cx3000a7,  13.56mhz plasma generator to
160,80, 40 meters. There wasn't room in the cabinet to put band-switch and new
tank circuit, so I bolted another chassis right on top. I increased the choke inductance in  filament, wound a bigger plate choke, added tuned input, cathode meter, a few relays.
Works great... a conservative full legal limit amp...

Good luck, Chuck

[W3SLK]

Conawingo Chuck said:

I recently converted a Henry 2000d, 3cx3000a7,  13.56mhz plasma generator to
160,80, 40 meters. There wasn't room in the cabinet to put band-switch and new
tank circuit, so I bolted another chassis right on top. I increased the choke inductance in  filament, wound a bigger plate choke, added tuned input, cathode meter, a few relays.
Works great... a conservative full legal limit amp...

I wouldn't mind having one of them. Even just the 3CX3000A7. Nice triode, that doesn't require any special socket. Just bolt to the chassis and the leads and you're good to go. Nothing like a little dynamic headroom

[W3FJJ]

Mikey, The 3000a7 needs a socket, I think its the 3000F7 that has the bolt connection,
other than that the specs are the same. Yeah killer tube, hard to destroy.

I wouldn't mind having one of them. Even just the 3CX3000A7. Nice triode, that doesn't require any special socket. Just bolt to the chassis and the leads and you're good to go. Nothing like a little dynamic headroom
[/quote]

[W3SLK]

Yep, UR right Chuck. It is the F7 variant. Still a nice ceramic triode with plent of umph!