Ifr 6000 test set message

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Ifr 6000 test set message

Postby Alisson2 » 15 Aug 2017, 06:21

Good night I wonder what is the meaning of the message (s reply timing) during the transponder test in the ifr 6000 test set. Thank you
Posts: 2
Joined: 15 Aug 2017, 06:11

Re: Ifr 6000 test set message

Postby maro12 » 15 Aug 2017, 20:33

Good Day Alisson2,

I suggest You google IFR 6000 Operation Manual and do some reading (available in Internet).

In the meantime...

XPDR - S Reply Timing Test verifies Mode S Reply:
-Jitter (difference between shortest and longest reply delay),
-Pulse Width (all pulses),
-Pulse Spacing (all pulses).

"Test Set interrogates UUT (Unit Under Test - Transponder system we are testing) with UF4."

UF4 - (Uplink Format 4) is a short, ground station request for altitude. It is initialised by ground station. So we are simulating interrogation in certain format and checking if aircraft answer is "on time" (checking reply delay) and if aircraft is answering in proper format.

"The Test Set interrogates UUT with UF4, 6 dB above MTL (Minimum Threshold Level), verifying reply is received with the same address and correct format.
The test verifies if reply delay minus range delay is:

128.00 μs (±0.25 μs) for Mode S

Measurements outside this tolerance result in a FAIL and are identified by an arrow.

NOTE: Range delay is 2.03 ns/ft (6.67 ns/m), calculated from the values in the Setup Menu."

For more Ref.IFR 6000 Operation Manual and other accessible sources.

Best Regards,
Posts: 72
Joined: 05 Oct 2008, 01:51

Re: Ifr 6000 test set message

Postby Alisson2 » 16 Aug 2017, 10:56

Good day maro12
thanks for the explanation.
Posts: 2
Joined: 15 Aug 2017, 06:11

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