FM transmitter power consumption? - RF Cafe Forums

RF Cafe Forums closed its virtual doors in late 2012 mainly due to other social media platforms dominating public commenting venues. RF Cafe Forums began sometime around August of 2003 and was quite well-attended for many years. By 2012, Facebook and Twitter were overwhelmingly dominating online personal interaction, and RF Cafe Forums activity dropped off precipitously. Regardless, there are still lots of great posts in the archive that ware worth looking at. Below are the old forum threads, including responses to the original posts. Here is the full original RF Cafe Forums on Archive.org

-- Amateur Radio

-- Anecdotes, Gripes, & Humor

-- Antennas

-- CAE, CAD, & Software

-- Circuits & Components

-- Employment & Interviews

-- Miscellany

-- Swap Shop

-- Systems

-- Test & Measurement

-- Webmaster

Mr.Whatever

Post subject: FM transmitter power consumption? Posted: Thu Sep 28, 2006 8:56 am

Captain

Joined: Fri Apr 07, 2006 6:10 pm

Posts: 18

Hi all,

I'm really not that familiar with a design of an FM transmitter, but I wanted to know about its power consumption. Does the power consumption fluctuate depending on amplitude of the input signal or is it constant regardless if there is an input or not?

I'm assuming that the antenna impedance remains constant during its operation.

Thanks!

Top

IR

Post subject: Posted: Thu Sep 28, 2006 2:00 pm

Site Admin

Joined: Mon Jun 27, 2005 2:02 pm

Posts: 373

Location: Germany

Hello,

In FM modulation the frequency of the carrier changes as a function of the modulating signal (Data), therefore the output power remains constant and thus the power consumption. If there is no input signal, the modulator will still transmit in the same output power and in the carrier frequency (Without frequency deviation), so the power consumption will still remain the same.

Hope that this helps!

_________________

Best regards,

- IR

Posted  11/12/2012