4. What function does a counter serve?
25 ‘ 7
Work in pairs. Prepare a short talk with your fellow-student on synchronous counters. Use ex. 23, 24. Then record your talk on a tape.
26 1
What is the name of this apparatus?
It is used for operating ammeters, wattmeters, and other measuring devices. It produces in the meters a current lower than the measured current but proportional to it. It also insulates the instrument from the circuit which is being measured. This is necessary for high voltage circuits.
27 9
Practice pronunciation. Open your textbooks and repeat after the speaker in pauses 3 paragraphs of the recorded text “Synchronous Counters”. Then close your books and do the same with paragraphs 4—9.
28 4
Dwell upon the subject of the story. Expand the ideas expressed in it.
One day Einstein was asked what the third world war would be like and what weapons would be used.
— I haven’t the slightest idea, — answered the' great scientist, — but I’m deadly certain men will have to use clubs, stones, knives, spears when the fourth world war breaks out. ..
The fourth class period
29 3
In the following sentences insert Infinitives.
1. Clear input permits ... counter in any time. 2. Each output may ...
to either level by entering the desired data' at the data inputs while the
load input is low. 3. The output will ... with data inputs independently of the count pulses. 4. This feature allows the counters ... as module-N dividers.
30 4
Choose the suitable Infinitive phrase to complete every sentence.
1. The counters are designed. .. 2. Both borrow and carry outputs are • available.... 3. He had taken extraordinary steps.... 4. Any absorption in this region is too weak. ... 5. It is possible that some errors may. . . .
6. For a long time the atom was thought.... 7. The transformer is
known. ... 8. Rubber and cotton insulations tend. . . . a) to be observed; b) to be cascaded; c) have resulted from careless operation; d) to burn up when wires are overloaded; e) to ensure the precision of measurements; f) to be a useful apparatus; g) to be indivisible; h) to cascade both the up and down counting functions.
31 3
Listen to 1—4 paragraphs of the text and translate them orally in pauses.
32 3
Respond to the questions. Compare your results with the text.
1. How can you tell when overflow occurs?
2. How can you tell when underflow occurs?
3. What is the function of clear input?
4. What is the function of data output?