In article , Brian Gaff (Sofa)
scribeth thus
Yes but he presumably meant dab and FM, presumably the latter as the
modulation type on digital is more complex and a lot more powerful due to
the duty cycle.
After all you are just sending a movable blank carrier on fm, more or less.
I think they probably my use travelling wave tubes at uhf though not sure
about the dab as that is band 3.
With regard to Long wave, there are whole transmitters around I think that
could be used at those low frequencies, but its true, the more specialist
the valve, the less likely it is to be available against when everyone was
using them. I'd imagine the low end of Medium wave type transmitters use
similar devices but the current Long wave transmitter is much higher power
than most of the medium wave outlets.


Brian


We look after a small DAB system that comprises of a modulator thats
running a bit of free open source software on a small NUC machine. That
drives a small universal software programmable driver unit. The output
of that goes to a linear Class A power amp of a 100 watts capacity
thence to a sharp passband filter and then to the aerials.

All there is to that bigger systems will have a somewhat more elaborate
mod and driver and a larger amp system by makers such as Rodent and
Black in Germany!


https://www.rohde-schwarz.com/uk/pro...d-media/radio-
transmitter/pg_overview_64079.html

or..

https://tinyurl.com/y4cexbtu
--
Tony Sayer


Man is least himself when he talks in his own person.

Give him a keyboard, and he will reveal himself.