Buried in a multi page thread here a couple months ago https://www.part15.org/community/transmitter-talk/the-best-am-transmitter/#post-57801 there was some talk about the Grain Industries transmitter.. below are copy of the 2 key post:
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■Mark: My input to this transmitter thread. With the exception of the Wayne Miller Grain Industries transmitter that has audio only to 3K?, ...but if your receiver squeezes that into a compressed band width typical of "run of the mill" receivers which can be to 2.5-3kLz in a shrill little 2" speaker that's very hard to listen to and crappy tiny audio chip it won't sound very good, .....
■Carl:
The main objection always mentioned about the Grain Industries Wayne Miller Transmitter is its frequency roll-off above 3 kHz. But we should know by now that frequency range merely states the flat portion of the response above which the response 'rolls off', and the reason we have multi-band equalizers is to set a compensating boost to restore the higher range until we have the frequency response we desire. I would not rule out the Grain Transmitter based on its published frequency response."
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Well, I got to thinking about that, and while I don't fully understand what either of them are saying, it did make me consider how it is many (most?) part 15 FM transmitters do not broadcast in stereo, the reason being it decreases it's range.. in other words it's more efficient to broadcast FM in mono.
So, with that in mind, is it possible that the guy designed the Grain Industries AM transmitter with a 3k audio response to make it a more efficient use of power or signal for the sake of increased range?
Or is my speculation totally flawed?
