JPS6131654B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a received signal mixer for television or FM radio.

For example, television broadcasts use both VHF radio waves and UHF radio waves, each of which is received by a separate antenna. When considering a television public listening system, the signals received by different antennas are mixed and sent to the same line. Here, the signals to be handled by the public listening system are outside the television signal.
Even with FM signals and television signals, depending on the direction of the broadcasting station, it may be necessary to handle the received signal with a separate antenna for a particular channel in the VHF or UHF band.

In such cases, conventional measures have been taken, such as changing the circuit configuration of the mixer depending on the situation in a particular region.

However, changing the design for each case in this way is extremely inconvenient for mass production.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a signal mixer suitable for mixing signals in various combinations and suitable for mass production.

In order to achieve this objective, the present invention includes a basic circuit for mixing a plurality of antenna signals and an additional circuit that is coupled to this basic circuit to interrupt a specific antenna signal and change the mixing content of the signals. The signal mixer is configured on separate circuit boards, and these circuit boards are partially overlapped and fixed to each other to make mechanical and electrical connections.

Embodiments of the present invention will be described with reference to the accompanying drawings.

FIGS. 1a and 1b show the internal circuit configurations of the basic circuit board BU and the additional circuit board CU of the signal mixer according to the present invention. Of these, the basic circuit shown in FIG. 1A becomes a normal mixing circuit for mixing UHF and VHF television signals by interconnecting the connection pieces A and B of connection sections 1 to 3. In this case, the UHF input terminal U-ANT is 300Ω, and the VHF input terminal V-ANT is 75Ω. and UHF
The input is passed through the impedance conversion circuit BAL and high-pass filter HPF to the output terminal OUT.
The VHF input is applied to the output terminal CUT via a low pass filter LPF.

On the other hand, the additional circuit CU in figure b is for mixing another UHF signal into the mixing circuit in figure a, and is the UHF input terminal U in the mixing circuit in figure a.
- Block the signal of a specific channel in the signal from ANT, and make this specific channel another UHF
This uses input. That is,
When connecting pieces A' and B' of connection part 1 of the additional circuit CU are connected to connection pieces A and B of connection part 1 of the basic circuit BU, the signal of a specific channel in the signal from U-ANT is passed through a band rejection filter. It is blocked by the BOF and is no longer transmitted to the high pass filter HPF, whereas the signal of a specific channel among the signals from U-ANT ₂ is transmitted to the high pass filter HPF after passing through the band pass filter BPF. As a result, the UHF input receives the U-ANT ₂ signal for a specific channel, and accepts the U-ANT signal for channels other than the specific channel. The connection part 2 is for common grounding between the basic circuit BU and the additional circuit CU.

Figures 2a and 2b show other examples of additional circuits. Figure 2a shows a specific channel of a VHF signal.
Figure b shows the FM signal mixed. In this case, the additional circuits CUa and CUb are connected to the connections 2 and 3 of the basic circuit BU. As a result, in the case of figure a,
Three antenna inputs: UHF x 1, VHF x 2,
Furthermore, in the case of figure b, three antenna inputs, one each of UHF, VHF, and FM, can be mixed.

3a, b, and c show the connection relationship between the basic circuit board BU and the additional circuit board CU. Here, both circuit boards BU and CU are double-sided printed circuit boards, and by overlapping their ends as shown in Figure b, side A of the basic circuit board BU and side A' of the additional circuit board CU are connected. and the B side of the basic circuit board BU and the B' side of the additional circuit board CU are connected with screw 1.
1 and the receiving fitting 12 are used to make electrical connection, and at the same time, by tightening the screw 11 and the receiving fitting 12, the mechanical connection of both circuit boards BU and CU is also made. It is more desirable that the receiving bracket 12 be soldered to the B-side conductor of the basic circuit board BU. Further, by making the end of the receiving metal fitting 12 protrude toward the opposite side of the basic circuit board BU, as shown in FIG.

Figure 4 shows the above basic circuit board BU and additional circuit board.
This shows an example of the configuration of a case that houses a CU, and here it has a drip-proof structure. In the same figure, 101 is a lid, and 102 is a base. Two circuit boards BU and CU are attached to this base 102, and the lid 1 is attached to the base 102.
Cover with 01. The lid 101 is inserted from one end of the base 102, and the hole 101a of the lid 101 is inserted into the base 102.
and the protrusion 102a. On the back of the base 102, a U-bolt 103, a tightening fitting 104, and a talking nut 105 for attaching a pole are attached. Signals are exchanged between the two circuit boards BU and CU inside this case and an antenna, a receiver, etc. using a cable connection section provided on the end surface of the base 102. This cable connection portion is covered with a rubber boot 106 to prevent dripping.

FIG. 5 shows a case for mounting the additional circuit board CU, which is used in combination with the case of FIG. 4, and a structure for mounting the additional circuit board CU to this case. This case for the additional circuit board CU is designed to prevent damage to the filters BOF, BPF, so that it is convenient to install the additional circuit board, i.e. the additional circuit board CU can be installed in precise alignment with the basic circuit board BU. It has various functions such as preventing

Figures 6a, b, c, d, and e show the external appearance and internal structure of the case shown in Figure 4, with figure a being a front view, figure b being a bottom view, and figure c being a right side view. Top view, Figure d is a right sectional view, Figure e is a rear view, Figure f is the base 1 with both boards BU and CU installed.
FIG. 02 is a front view of the ball 200, and FIG. This case is U bolt 1
It can be attached to the ball 200 using a U bolt 103 or the like, or it can be attached to a wall surface or the like using a screw or the like after storing the U bolt 103 or the like. In either case, the cover 101 can be opened in the installed state to perform connection work for the basic circuit board BU, additional circuit board CU, etc.

FIG. 7 shows another connection method between the basic circuit board BU and the additional circuit board CU. By adopting a three-terminal configuration as shown in the figure, the additional circuit board CU can also be made into a single-sided printed board.

As described above, the present invention has a basic circuit board for mixing a plurality of antenna signals, and an additional circuit board for interrupting a specific antenna signal. Since the mixer can be connected to the mixer, it is possible to easily configure a mixer that can arbitrarily interrupt a desired signal by simply selecting an appropriate additional circuit.

[Brief explanation of the drawing]

Figures 1a and b are diagrams showing the circuit configuration of a basic circuit and an additional circuit used in combination with this basic circuit in one embodiment of the present invention, and Figures 2a and b are applicable to the embodiment of Figure 1. Figure 3 shows another example of circuit configuration.
Figures a, b, and c are explanatory diagrams showing the connection structure between the basic circuit board and the additional circuit board in one embodiment of the present invention, Figure 4 is an explanatory diagram showing the case structure of the mixer according to the present invention, and Figure 5 The figure is an explanatory diagram showing the structure of the additional circuit case used in combination with the case in Figure 4.
Figures a to g show the structure of the mixer case in Figure 4 in more detail: a front view, a bottom view, a right side view, a right sectional view, a rear view, a front view with the lid removed, and a view with the pole attached. The right side view of FIG. 7 and FIG. 7 are explanatory views showing other embodiments of the basic circuit board and the additional circuit board used in the present invention. BU...Basic circuit board, CU...Additional circuit board, HPF,
LPF, BOF, BPF...Filter, 11...Screw, 1
2...Bracket, 101...Lid, 102...Base, 10
3...U bolt, 104...tightening metal fitting, 105...wing nut, 106...rubber boot, 107...additional circuit case.

Claims (1)

[Claims] 1. A basic circuit for mixing multiple antenna signals and an additional circuit that is coupled to this basic circuit to interrupt a specific antenna signal and change the mixed content of the signals, each of which is constructed using separate circuit boards. and a signal mixer in which mechanical and electrical connections are made by partially overlapping and fixing these circuit boards to each other.