Differences

This shows you the differences between two versions of the page.

--- howto:hambasics:b003 [2019/11/27 19:47] – [FM Receiver] ve7hzf
+++ howto:hambasics:b003 [2020/02/20 19:04] – [Transmitters] va7fi
@@ Line 1: / Line 1: @@
-<box orange |**Under Construction**>
+|<100% ----- >|
-''VE7HZF'' is editing this section, please do not edit it until this notice is taken down.
+|  [[home |Ham Basics]]  |  [[test |About The Test]]  |  [[Reference |References]]  ^  [[sections |Study Sections]]  |
-</box>
+<WRAP round todo center box 60%>
+ **Under Construction**: VA7FI is editing this section, please do not edit it until this notice is taken down.
+</WRAP>
 ====== 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 =====
@@ Line 22: / Line 30: @@
 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.
-===== To Review =====
+===== Transmitters =====
+<WRAP round info box center 80%>
+**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 //AM// and //FM//.
+</WRAP>
-<box blue 80%>
-For the next few 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.
-  * the difference between //AM// and //FM//.
-</box>
-===== FM Transmitter =====
+==== 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 }}
@@ Line 40: / Line 56: @@
   * The **frequency multiplier** increases the frequency of the modulated signal by a factor of 2, 3, or 4.  This is so that the oscillator frequency can be lower than the frequency transmitted at 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.
 {{ :howto:hambasics:3_3.png }}
-Before we look at individual components, it's important to highlight an important trick: 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.
   * The **RF amplifier** increases the strength of the weak radio signal received by the antenna.
@@ Line 52: / Line 89: @@
   * The **frequency discriminator** extracts the baseband signal.
   * The **audio amplifier** increases the strength of the baseband signal before passing it to the speaker.
+==== SSB/CW Receiver ====
+{{ :howto:hambasics:3_5.png }}
+===== Digital System =====
+{{ :howto:hambasics:3_7.png }}
+===== Regulated Power Supply =====
+{{ :howto:hambasics:3_8.png }}
 ====== Questions ======
   * B-003-001-001 -> B-003-003-010
-[[sections |{{/back.png }}]] [[waveinterference |{{  /next.png}}]]
+[[propagation |{{/back.png }}]] [[section |{{  /next.png}}]]