Ray, the plate modulation idea was published among a spate of No.19 set articles in A U.K. mag, name escapes me at moment, but it will come to me later. I do not want to look up any of those right now and anyway you don't want to do these hacks. The thing abt plate modulation is, you have a sealed cabinet with no air travel to cool the innards. You really want to introduce some tube like the single ended 6L6 in that cabinet ? 

I only have about 5 minutes experience with the No. 19 and that was several decades ago. It astonished me that with the antenna vario it could work a short wire, like no more than 7 foot or so, on 80 meters. 

More: there was a Canada ham who wrote maybe 4 years back about removing the mod limiter tube, and it worked fine, maybe better. This is something like 6H6 ? I can maybe find the email. Also i asked, maybe on U.K. milsurp group, abt removing the IF loading resistors, but someone replied that the set would "take off". I don't necessarily believe that and having dealt with similar before, think i could devise successful countermeasures. 

I think you know that someone in USA spanned the Atlantic with the No.19. 

I have maybe 5 of No.19 from radio alone to maybe 2 complete. I like them but you can't keep everything, the clock is always running and i don't want my story to end like the big estate sales i'm aware of in the last couple years out here in OR and WA. So i don't know if i will keep anything of this set. Don't worry, i won't run out of projects ! 

BTW, the W.S. No.19 Mark III is the one to own. Vernier drive improves the otherwise scarey tuning rate; has an RF gain control, and a basic CW note filter. 

I recall many years ago, i met a gentleman, US Army vet, who was in some kind of special map making vehicle that accompanied the Allied advance into Germany. He said the vehicle included a 19 set, an anomaly in US use, to liaise with UK forces. 

I was fortunate to acquire a couple pages of ads from a Seattle department store  touting the No.19 they were selling. Odd, but there was a sudden tide of the things, as they were built here but not used by our military.

-Hue Miller

copy to Julyah, Pres. of PSARA. She has 2 No.19 she rescued from some falling down building.