There is no such big differences between a light emitting (LED) and a light receiving diode (photodiode), they are just the reverse of each other. In fact photodiodes can even emit light, but very inefficiently. Same in reverse, LEDs can also detect light, just badly.
It seems like most efficient energy conversion methods can be used in both directions.
Yes, but you would blow out most of the amplification circuitry in a radio telescope reciver if you tried to use it for broadcast at any kind of power.
An LED (or photodiode used as one) is a fairly simplistic device compared to an assembled receiver / transmitter. Just like you can burn gasoline in a car but you can’t push a car to turn the engine to make gasoline - it’s a complex system that really only works one way.
There is no such big differences between a light emitting (LED) and a light receiving diode (photodiode), they are just the reverse of each other. In fact photodiodes can even emit light, but very inefficiently. Same in reverse, LEDs can also detect light, just badly.
It seems like most efficient energy conversion methods can be used in both directions.
Yes, but you would blow out most of the amplification circuitry in a radio telescope reciver if you tried to use it for broadcast at any kind of power.
An LED (or photodiode used as one) is a fairly simplistic device compared to an assembled receiver / transmitter. Just like you can burn gasoline in a car but you can’t push a car to turn the engine to make gasoline - it’s a complex system that really only works one way.
Nothing gets burned or otherwise destroyed when receiving EM radiation via a dish and converted it into electricity via a receiver.
Sure, the amplification stage of the process likely works only one way, and should be replaced in order to send something.
The one way process of burning oil to generate heat seems much more primitive than the energy conversion offered by a diode, TBH.
You can push or tow an electric car and charge their batteries. Because electric motors are also generators.
Even with your simplistic fossil fuel car in your example the alternator within can also be used as a motor.
Not by “simply reversing the flow” it can’t. You’d need to remove and replace many components, just like the example of changing an Rx to Tx system