27-04-2022, 11:03 AM
(27-04-2022, 09:39 AM)ppppenguin Wrote: If you want multiple radio channels to receive in a museum environment then you can use multiple pantry transmitters fed by multiple audio sources.
It's not to demonstrate a radio working, or even multiple radios, but to demonstrate what using an actual AM band was like (rather than the radio), some time in the future when there are no manual analogue tuned radios and no AM stations. Thus multiple local AM sources are no use.
The wide band signals would be via induction to loop or ferrite aerials, or via attenuator to sets that only use an external aerial.
It's not for listening to an AM radio. It's to "replay" an historic AM band so as a visitor can experience what tuning AM was like. It could be somewhat faked by my scheme using pickup of a L.O. and simulation of the part of band the set is tuned to and using mp3 files or live satellite radio, but it wouldn't be the same as tuning the real LW, MW or SW bands.
So to recreate what's on air in the future when it's gone. The original proposal was made years ago, hence the idea of a VCR/VTR. But already there is little to record. I imagine any good simulation/historical replay of capture would have a selector for time of day/night.
Obviously the people discussing it and making recordings are totally familiar with ordinary low power AM fed by mp3, FM, DAB, Internet or Satellite. The word "pantry" is totally superfluous.
It's plausible that a simulation of an AM band using separate pre-recorded sources, artificial fading and noise could recreate 1920s, 30, 40, 50s & 60s AM radio bands in different countries, seasons and time of day. Play out entire band on an 18bit DAC and inductive/attenuator coupled. I think it could be done so it would seem real and match historical accounts. All that can be recorded now is the 2020s experience.
