I ran a DX-60 (original version) into an SB-200 with Bill, W3CK mods (
http://www.amwindow.org/tech/htm/wc3kmods.htm ). I had great audio reports and eventually I need to dig it all out of storage and maybe apply the un-controlled carrier mod to it so that carrier doesn't pump.
These mods allowed one to adjust the carrier which came in really handy. I would set it to put my SB-200 right at 100 watts output and If I recall that was anywhere from 8 to 12 watts depending on the band (from 80 to 10 meters). Pete is pretty close.
Remember these combinations (as well as the SB-220) were used a LOT from what I've read and heard so you should have no problems. I did have some issues with Chinese 572B's in the SB-200 losing emission really fast and watching output slowly fall over just one year. The original Sylvania branded 572B's (probably rebranded Cetrons) never gave any problems (until one of the rolled off the desk during a routine cleaning of the amp... oops).
RF Parts has visited their Chinese supplier last year with Cetrons in hand and made a deal for them to build the new ones to that standard. I actually bought a quad (not cheap, 300+ bucks) and have them in an Ameriton AL-811H and have been running them for only a month and a half now but so far so good, of course these are replacing 811A's at only 1750 volts on the plates so they are "loafing" in this amp. 4 tubes to get what 2 tubes in the SB-200 gives at 2200-2300 loaded.... but I'm hoping they last a lifetime.
Have fun!
John
