JPS5833742B2 - Multi-frequency signal receiver test equipment - Google Patents

Description

[Detailed description of the invention] The present invention relates to a testing device for a multi-frequency signal receiver.

Here, a multi-frequency signal receiver is one that receives a plurality, for example, two combined signals selected from a plurality of signals of six frequencies, for example, and outputs them to an output terminal corresponding to the combined frequency. For example, it is used when transmitting connection information via a trunk line in a telephone switching system.

When this multi-frequency signal receiver receives a combination of multi-frequency signals, it generates an output at the output terminal corresponding to the combination, and for example, it displays 1 for the combination of frequencies fo and fl. At the output end, there is also a frequency f.

In the combination of and f2, at the output terminal that displays 2,
..., etc., and send out the output.

When testing the operation of a multi-frequency signal receiver, we ensure that there is no level difference between the standard frequency, standard level, and dual-frequency signals, and that the noise is below a certain level when receiving a standard multi-frequency signal. In addition to testing whether it works normally, the frequency of the received signal, the level difference between the level two frequency signals,
It is necessary to test whether the device operates normally even with noise and other signals that easily satisfy the standard values.

Therefore, testing of multi-frequency signal receivers requires expensive precision oscillators and AC voltmeters due to the above-mentioned signals, requires complicated operations, and takes time to test. It took a while.

An object of the present invention is to eliminate the need for expensive and precise oscillators and AC voltmeters, and to quickly test multifrequency signal receivers with simple operations.

Next, the present invention will be explained with reference to the drawings.

The figure shows the configuration of an embodiment of the present invention, and the multi-frequency signal receiver testing device according to the present invention includes a tape recorder MT, a reference signal receiver RR, and a reference signal receiver RR as shown in the figure. A logic circuit for comparing and detecting a match between the output of each output terminal and the corresponding output of each output terminal of the multifrequency signal receiver under test, that is, the reference signal receiver and the multifrequency signal receiver under test. Exclusive OR circuit EOR, which inputs the outputs of the corresponding output terminals 1, 2 to n.

It is composed of EOR2 to EORn, etc.

The recording tape T of the tape recorder MT has at least two tracks, and the reference signal track TR includes a reference signal, for example, a reference frequency and a reference level signal, and the levels of two signals forming a multifrequency signal. If there is no difference and the noise level is sufficiently low, high-quality signals will be recorded for all required frequency combinations, and the test signal track TT will contain the reference signal recorded in the reference signal track TR. In other words, a test multi-frequency signal of a frequency combination corresponding to A good quality multi-frequency signal is also recorded as one of the tests.

Therefore, when the tape T is run at a prescribed speed in the direction of the arrow, the reference signal is transmitted to the head HR for the reference signal track TR, and the head HT for the test signal track TT receives the reference signal.
The test multi-frequency signals are simultaneously reproduced.

Both reproduced signals are amplified by amplifiers A and A2, respectively, and reach the input terminal IR of the reference signal receiver RR and the input terminal IT of the multifrequency signal receiver under test TR, respectively.

Now, the frequency f is a multi-frequency signal.

It is assumed that a reference signal and a test multi-frequency signal for a combination signal of and fl are generated from tape recorder MT.

Then, the frequency f of the reference signal receiver RR.

A signal R is output to output terminal 1 corresponding to the combined signal of and fl.
1, and the other output terminals 2 to n do not send out the signals R2 to Rn.

The multi-frequency signal receiver under test TR receives the frequency f from its input terminal IT.

A test multi-frequency signal of a combination of and fl is received.

If it is normal, it sends out a signal T1 of 1'' to the output terminal 1 like the reference signal receiver RR, and the other output terminals 2 to n do not generate signals T2 to Tn.

At this time, outputs R1, T1, and R2 from the corresponding output terminals of the reference signal receiver RR and the multifrequency signal receiver under test TR
and T2~Rn and Tn are exclusive OR circuits EOR, ,E
Each of OR2 to EORn is compared.

If they match, the exclusive OR circuits EOR1 and EOR
2~EORn outputs 11011, and if there is a mismatch, 1″
Output.

Therefore, the exclusive OR circuits EOR1, EOR2 to E
If the outputs of ORn are all 0'', it is determined that the multi-frequency signal receiver under test TR is normal.

In the above, if the multi-frequency signal receiver under test TR does not output °゛1'' as the output T1 to the output terminal 1, the output of the exclusive OR circuit EOR1 will be 1'', and it will not correspond. If 1'' is output as the signal Tn to the output terminal, for example n, the output of the exclusive OR circuit EORn becomes u 1
It becomes +1.

Therefore, the above exclusive OR circuits EOR1, FOR2 to EO
If the output of at least one of Rn becomes l'', it is determined that the multi-frequency signal receiver under test TR is not normal.

If the tape recorder MT is prepared with reference signals and test multifrequency signals for all the multifrequency signals scheduled to be received, the multifrequency signal receiver can be tested by running the tape T once. end.

In order to attach the multi-frequency signal receiver under test to the test equipment, the test equipment should be equipped with a connector in the form of a jack for each terminal of the multi-frequency receiver under test TR to facilitate attachment and removal. It can be done.

In this embodiment, a reference signal receiver having the same configuration as the multifrequency receiver under test can be used.

The present invention is not limited to the above embodiments, and various modifications are possible.

For example, instead of using a two-frequency combined signal corresponding to a multi-frequency signal as the reference signal, a signal of another format (single frequency, etc.) that can indicate the type of signal, that is, the combined two frequencies, is used to receive the reference signal. It is also possible to use a device having a configuration different from that of the multi-frequency signal receiver under test, which sends an output to a corresponding output terminal when receiving the above-mentioned signal indicating two frequencies.

Since the test device according to the present invention is configured as described above, it does not require expensive oscillators, AC voltmeters, etc., and tests can be carried out with simple operations, and the multi-frequency signal receiver under test can be tested in a short time. It has the effect of allowing you to complete the exam.

In the illustrated embodiment, there is an advantage that a reference signal receiver having the same configuration as the multi-frequency signal receiver under test can be used.

[Brief explanation of drawings]

The figure is a diagram showing the configuration of an embodiment of the present invention. RR...Reference signal receiver, TR...Multi-frequency signal receiver under test, MT...Tape recorder, T...Tape, TR... ...Reference signal track, TT...Test multi-frequency signal track, HR...Reference signal head, HT...
...Multi-frequency signal head for testing, A1 TS A2...Amplifier, OR1, EOR2 EORn...Exclusive OR circuit.

Claims (1)

[Claims] It has a recording tape in which a reference signal corresponding to a multi-frequency signal is recorded in 11 tracks and a test multi-frequency signal corresponding to the reference signal is recorded in another track, and the above-mentioned signals are simultaneously reproduced by different heads. a tape recorder for transmitting the signal; a reference signal receiver for receiving the reference signal and outputting it to an output end corresponding to the received reference signal; and a multi-frequency signal receiver under test configured to receive the test multi-frequency signal. 1. A test device for a multi-frequency signal receiver, comprising a logic circuit that compares the output of the output terminal of the receiver and the output of the corresponding output terminal of the reference signal receiver to detect a match.