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howto:hambasics:b003 [2019/12/14 21:47] – va7fihowto:hambasics:b003 [2020/02/20 19:04] – [Transmitters] va7fi
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 +|<100% ----- >|
 +|  [[home |Ham Basics]]  |  [[test |About The Test]]  |  [[Reference |References]]  ^  [[sections |Study Sections]]  |
 +
 <WRAP round todo center box 60%> <WRAP round todo center box 60%>
  **Under Construction**: VA7FI is editing this section, please do not edit it until this notice is taken down.  **Under Construction**: VA7FI is editing this section, please do not edit it until this notice is taken down.
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 ====== Station Assembly, Practice and Safety ====== ====== Station Assembly, Practice and Safety ======
 +
 +===== Block Diagrams =====
 +The next few sections use block diagrams to illustrate the configuration of various pieces of equipment.  Here's an excellent introduction that should help with what follows:
 +
 +{{ youtube>3VXnhIeeT6c }}
  
 ===== HF Station ===== ===== HF Station =====
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 All that being said, it's possible to go on HF with a transceiver that has an small integrated tuner in it, and a single antenna.  It'll just be a matter of knowing which frequencies your system can transmit on, and stay within them. All that being said, it's possible to go on HF with a transceiver that has an small integrated tuner in it, and a single antenna.  It'll just be a matter of knowing which frequencies your system can transmit on, and stay within them.
  
- +===== Transmitters =====
-===== FM Transmitter =====+
 <WRAP round info box center 80%> <WRAP round info box center 80%>
-=== To Review === +**Review** the [[wavemodulation |Wave Modulation]] page.  You should:
-For the next two sections, review the [[wavemodulation |Wave Modulation]] page.  You should:+
   * understand the difference between the //baseband// signal and the //carrier//, and how they combine to form the //modulated// signal.   * understand the difference between the //baseband// signal and the //carrier//, and how they combine to form the //modulated// signal.
   * understand the difference between //AM// and //FM//.   * understand the difference between //AM// and //FM//.
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 +==== CW Transmitter ====
 +{{ :howto:hambasics:3_4.png }}
 +
 +  * The **master oscillator** generates a stable sine wave signal at the rest frequency.
 +  * The **driver / buffer** is the first stage in the amplification process.
 +  * The **key** is basically an on/off switch used to let the signal through to the amplifier or block it.
 +  * The **power amplifier** is the last stage of amplification before the signal is released to the antenna.
 +
 +
 +==== FM Transmitter ====
 {{ :howto:hambasics:3_2.png }} {{ :howto:hambasics:3_2.png }}
  
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   * The **amplifier** increases the power of the signal to be transmitted by the antenna.   * The **amplifier** increases the power of the signal to be transmitted by the antenna.
  
-===== FM Receiver =====+ 
 +==== SSB Transmitter ==== 
 +{{ :howto:hambasics:3_6.png }} 
 + 
 +  * The **microphone** picks up the sound waves carried by the air and converts them into a weak electrical signal that becomes the //baseband//. 
 +  * The **speech amplifier** increases the strength of the baseband signal before it can modulate the carrier.  
 +  * The **RF oscillator** generates a stable sine wave signal at the rest frequency. Note that the oscillator frequency can be much lower than the final transmitted frequency.  
 +  * The outputs of the speech amplifier and the RF oscillator are mixed together in the **balanced modulator**. This produces a signal with two side bands, only one of which we want to keep. 
 +  * The **filter** only lets one sideband through. 
 +  * The **VFO** creates a sine wave frequency that can be varied. 
 +  * The **mixer** uses the output from the filter and the VFO to generate a higher frequency signal. 
 +  * The **linear amplifier** increases the power of the signal to be transmitted by the antenna. 
 + 
 +<WRAP important center round 80%> 
 +Note that a [[wp>Frequency_mixer |Frequency Mixer]] //multiplies// two signals together, which usually results in a total of four (or more) frequencies.  This is not to be confused with an [[wp>Mixing_console |Audio Mixer]], which //adds// different signals together.  See the optional [[wavemodulationmath#mixer | Wave Modulation Math page]] for more details. 
 +</WRAP> 
 + 
 +===== Receivers ===== 
 + 
 +==== FM Receiver ====
 Before we look at individual components, there's an important step we should highlight: The received radio frequency (RF) is converted down to a predetermined intermediate frequency (IF) before being processed further.  This solves a lot of problems that plague simpler receivers.  Now let's look at the details. Before we look at individual components, there's an important step we should highlight: The received radio frequency (RF) is converted down to a predetermined intermediate frequency (IF) before being processed further.  This solves a lot of problems that plague simpler receivers.  Now let's look at the details.
  
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   * The **audio amplifier** increases the strength of the baseband signal before passing it to the speaker.   * The **audio amplifier** increases the strength of the baseband signal before passing it to the speaker.
  
-===== CW Transmitter ===== 
-{{ :howto:hambasics:3_4.png }} 
  
  
-===== SSB/CW Receiver =====+==== SSB/CW Receiver ====
 {{ :howto:hambasics:3_5.png }} {{ :howto:hambasics:3_5.png }}
- 
- 
-===== SSB Transmitter ===== 
-{{ :howto:hambasics:3_6.png }} 
- 
  
 ===== Digital System ===== ===== Digital System =====
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   * B-003-001-001 -> B-003-003-010   * B-003-001-001 -> B-003-003-010
  
-[[sections |{{/back.png }}]] [[waveinterference |{{  /next.png}}]]+[[propagation |{{/back.png }}]] [[section |{{  /next.png}}]]