2.19 RESP - Frequency Response
The frequency response test, RESP, may be used to check that the
variation in power loss of a telecommunications or audio transformer over
a specified frequency range is less than specified limits.
The RESP test consists of a number of Insertion Loss (ILOS) tests
repeated at different frequencies.
The resistors shown are fitted to the test fixture and should be switched
out of circuit when making other measurements such as resistance and
This can be done by fitting relays to the fixture and switching them at
appropriate points in the test program using OUT tests.
The first ILOS test is made at a reference frequency that is usually near
the middle of the band of frequencies of interest.
The result of this test is the 0dB reference level. Further ILOS tests
are then carried out at user selected frequencies and the results referred
to the reference dB level.
If all the referred ILOS results are at or inside the specified limits,
the result of a RESP test is the referred ILOS result that is closest to
If any of the referred ILOS results are outside the specified limits, the
RESP result is the referred ILOS result that is furthest away from the