Syl's Old Radioz wrote:

"Patrick Turner" a écrit dans le message

I don't expect anyone to pay 3c for what I say, which could be seen as OT.

You just met our village idiot it seems...

There is an unspoken rule here..._Ignore_ his posts. Let him talk to
himself.

We don't get into fight with village idiot like you do on RAT...Keeps rar+p
"clean"...;o)

Syl

Well, with all due respects to all gentlemen and possible idiots
on all groups to whom this subject thread is cross posted to,
I reserve the right to decide who I will ignore or not.

I will desperately try not step on anyone's toes as I act in well intentioned
freewill.

I won't budge from the idea that its possible to digitise the signal from the
antenna and simply apply
suitable algorithms, and get digital decoding, without all the phase shift
caused by consecutive tuned circuits.
Like on expensive CD players, a tubed output filter on the final DA converter
could be used,
and a decent sound could be had, at least in Oz, where the audio transmitted by
AM is often very
wide bandwidth, depite the fact that the networked stations send their radio
shows to air at different times,
and via satellite, before finally being broadcast by a local AM transmitter.
God knows how many links the signal goes through, afaik.

I have tried to address the problems caused by tuned circuit delays in
recommending
that 2 MHz IFTs be used.
I do think tubes are good for IF amps, certainly the last IF amp, because
of the huge dynamic range of the tubes, and far better performance
can be had compared to using j-fets and a lousy 12 volt B+ supply.
Some might argue silicon opamps would be better still.
I would have no objection to whatever they used, as long as it
achieves the goal of high quality sound, and it was a valid way of doing it, as
far as they were concerned.
But a j-fet balanced converter and first IF amp would be permissable
because the signals are so low before they get to a second and final IF amp.

To get ideal signal from an AM tubed receiver, the AF signal
from a 100% modulated AM IF carrier should be around 2vrms
at least, so the tube isn't working beyond its linear class A range.

Anyone have anything to say about this?

Patrick Turner.