I want to calculate mark space ratio: f=25000Hz,T=4us

AI Thread Summary
The discussion centers on calculating the mark to space ratio based on a frequency of 25,000 Hz, which results in a mark time of 0.4 μs. The space time is derived as 3.6 μs, leading to a mark to space ratio of 1:9. There is confusion regarding the mention of 4 μs, which is clarified as part of the original question, indicating a total cycle time of 40 μs. Participants seek clarification on the definition of "mark to phase ratio," as it is not a commonly used term in this context. The conversation emphasizes the importance of understanding the relationship between frequency, mark time, and space time in waveform analysis.
engnrshyckh
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i know that mark time is duration in which a pulse is present and space time is a duration is which pulse is not present. my attempt to ques is: f= 25000Hz...> t=1/f=0.4us which means pulse is present for 0.4us. that is mark time is .4us. space time 4-0.4=3.6us s therefore:
Mark:space= 0.4:3.6
=4:36,,,...>1:9 please tell me if i my calculation is faulty. Also what will be mark to Phase ratio
 
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The period of a complete cycle is the reciprocal of frequency.
 
Asymptotic said:
The period of a complete cycle is the reciprocal of frequency.
25000hz leads to 0.4us not 4us so something is missing :P
 
engnrshyckh said:
25000hz leads to 0.4us not 4us so something is missing :P

1/25 KHz = 1/25 ms. 1/25 ms = 0.04 ms.
0.04 ms = 40 μs total period.
Total time = Mark time + Space time

engnrshyckh said:
space time 4-0.4=3.6us
Where did the 4 μs value come from?

How is this "mark to phase ratio" defined? It's new terminology to me.
 
Asymptotic said:
1/25 KHz = 1/25 ms. 1/25 ms = 0.04 ms.
0.04 ms = 40 μs total period.
Total time = Mark time + Space timeWhere did the 4 μs value come from?

How is this "mark to phase ratio" defined? It's new terminology to me.
4us is given in question... if i simplify the question then i want to find mark to space and mark to phase ratio given the frequency and time period. i havnt either heard about the letter
 
If a single cycle of the waveform is 40 μs wide, and the mark time is 4 μs wide, then what is the duration of the 'space'?
 
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