In article . com,
Radium wrote:
Hi:

What is the minimum amount of photons-per-second needed for a 150 KHz
AM radio carrier wave to transmit audio signals? Around 20,000-photons-
per-second?


1. What is the energy of a photon at 150 kHz?

2. What is the minimum discernable signal in your receiving system?
(How much power is needed at the receiver to overcome the internal
noise of the receiver system and detect the signal?)

3. What signal to noise ratio makes for a tolerable listening condition?
(How much more power than quetion #2 is needed at the receiver to decode
the modulation and yield a usable signal?)

Mark Zenier
Googleproofaddress(account:mzenier provider:eskimo domain:com)

On Jun 18, 11:05 am, (Mark Zenier) wrote:

1. What is the energy of a photon at 150 kHz?

6.2 X 10^-10 eV

In article . com,
Radium wrote:
On Jun 18, 11:05 am, (Mark Zenier) wrote:

1. What is the energy of a photon at 150 kHz?

6.2 X 10^-10 eV


You didn't answer the other questions. How much power does a good radio
need to get a listenable signal?

Here's some numbers

input impedance 50 ohms
Noise Figure 5 db
Bandwidth 6 kHz
signal to noise ratio 40 dB

(This would be what some of the newsgroups listeners here would want if
they had one of their pretty damn good radios listening to a broadcast
station. Really picky ones would probably want a 8-15 kHz bandwidth
with a 60 dB s/N ratio).

There are equations out there that will give you how much power
you need for this signal...

Mark Zenier
Googleproofaddress(account:mzenier provider:eskimo domain:com)