1. . . .
Vocabulary
mixing valve
tuned aerial
intermediate frequency
high fidelity
low sensitivity
condenser capacity
sensitivity control
near-earth space -
TYPES OF TYPES OF RADIO RECEIVERSS
What are the characteristics of a good radio receiver? They are as follows.A good radio receiver should have high selectivity, high sensitivity and fidelity and low noise. Selectivity is achieved by a receiver receiving signals from one station and rejecting them from another station operating on a nearby frequency. A high-fidelity receiver contains both the tuner and amplifier circuits of a radio. And the high-fidelity radio may consist of a separate audio-amplifier and a separate radio tuner.
High sensitivity is achieved by having numerous stages of amplification. But it should be noted that high amplification is useful only if high fidelity of the system is achieved. It is also important to achieve as low noise as possible.
The most sensitive receivers have one stage of tuned radio-frequency amplification.
Questions
1. What are the main characteristics of a good receiver?
2. By what means is high sensitivity of the receiver achieved?
3. What device in a receiver generates a radio-frequency wave?
4. What signal does a radio-frequency wave mix with?
5. By what means is the aerial circuit tuned?
Task 2. Translate and write down the following words and word combinations in your workbooks. Make up a short plan of the text TYPES OF RADIO RECEIVERS and write it down in your workbooks, summarize the text in short.
2. . » , .
Short theoretical information and a sample of implementation
( )
Past Continuous Tense
Past Continuous Tense , , ,
to be .
not to be.
He was not passing the test at that moment. - .
to be , Past Continuous . ing - .
Was he passing the test at that moment? - ?
Choose the correct variant. .
- We did not like the studying of textbooks at all.
correct
incorrect - I were not reading a magazine.
correct
incorrect - They were not watching TV.
correct
incorrect - Where was he doing a language course?
correct
incorrect - The pupils were writing a test.
correct
incorrect - Who was testing our English?
correct
incorrect - At six o clock, we were having dinner.
correct
incorrect
Translate the following words and word combinations in written form.
|
|
|
.
Words
mix______________________
select_____________________
mixture___________________
selection__________________
Word combinations
intermediate frequency_______________________
low selectivity ______________________________
stages of amplification ________________________
Define what of the following words are nouns, verbs, adjectives? Fill in the table. Follow the model.
, , , . .
achievement, mix, tunable, remainder, selective, select, remain, achievable, selectivity, stage, reject, mixture, selection.
(Model):
| noun () | verb () | adjective () |
| noise - | to noise - | nosy - |
Task 3. Prepare a presentation of the topic TYPES OF RADIO RECEIVERS: make up slides about the topic TYPES OF RADIO RECEIVERS, write down the material of the slides in your workbooks, prepare your report (presentation) for the demonstration it in the lecture-room.
3. »: », , () .
8. 8. Unit 1.8. AERIAL
1.8.
