\[7 BROADS, ANTENI 2-6 Mt-

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1 E.ECTRONCS TECHNCAN 3 & 2 VOL. 1 to each antenna couper (1) a.c. to operate the cooing fans which remove the heat generated during operation and (2) d.c. to operate the contro and protective circuits. The power suppy pane aso contains an audibe aarm to warn the operator of a oss-of-air fow within any of the antenna coupers. Antenna Couper Group AN/SRA..;34A (V) Antenna Couper Group AN/SRA-34A (V) is a variabe group of antenna coupers, associated adapters, and switching units. The major units of the group are antenna couper group OA- 4794A, couper adapter MX-4845A, transmitter adapter MX-4847B, remote switching contro C-4787, and RF switching group incuding eectrica equipment cabinet CY and RF switching units SA-1070 as shown in figure Each of these major units is shown in figure 6-18 as a functiona section of the AN/SRA-84A (V); however, the quantity of each major unit suppied for a particuar AN/SRA-34A(V) system wi vary depending upon individua instaation requirements. For exampe, a specific instaation may require severa MX-4845A equipments and may not incude an MX-4847B unit. The AN/SRA-84A (V) units have one primary feature in common. A are intended for use in a dipex system of antenna couper contro. (A dipex system permits two RF signas to operate on the same transmission ine simutaneousy.) FUNCTON OF MAJO R UNTS.-Antenna Couper Group OA-4794A/SRA-84 (V) provides antenna couping between HF receivers and/or transmitters utiiing dipex contro, and shipboard antennas that cover the to MH frequency range. The OA-4794A/SRA-34 (V) consists of Eectrica Equipment Cabinet CY -4082A/SRA-34 (V) and four Antenna Couper CU-1169/SRC-16 units. The OA-4794A/SRA-84 (V) is capabe of accepting up to four RF input channes. Channe spacing is dependent on the particuar receiver and/or transmitter in use. The RF power handing capabiity of each channe is 5 kw peak enveope power, and 2.5 kw average. The CY-4032A/SRA-34 (V) contains a watercooed heat exchanger which permits interna cosed-cyce air cooing_ for the CU-1169/ SRC-16 units. r------, REMOTE SWTCHNG CONTROL C-4787/SRA-34(V) L (NOTE ) _j REMOTE SWTCHNG CONTROL C-4787/SRA-34( V) \[7 BROADS, ANTEN 2-6 Mt- GROUP OA-4794/SRA-34A(V) FROM RADO SET AN/SRC-23A - V) RF SWTCHNG GROUP ELECTRCAL EQUPMENT CABNET CY-4033/SRA-34(V) AND RF SWTCHNG UNTS SA-1070/SRA-34( V) i ADAPTER MX-4845A/SRA-34V) TO TO TRANSMTTE R- TRANSMTTER ADAPTER MX SRA-34(V) NOTE. ADDTONAL REMOTE SWTCHNG CONTROLS (MAX. OF 4) MAY BE NTERCONNECTED; ONE FOR EACH RF SWTCH NG UNT SA-10 70/SRA-34\V) Figure Antenna couper group AN/SRA-34A(V) functiona bock diagram. 164

2 Chapter 6-CW AND VOCE COMMUNCATON SYSTEMS Couper Adapter MX-4845A/SRA-34 (V) adapts the contro circuits of various antenna coupers to the dipex antenna couper contro system. Compatibiity with the AN/SRA-13 through AN/SRA-16, AN/SRA-22, AN/SRA-56 through AN/SRA-58, and AN/URA-38 may be achieved by use of one of the jumper pug assembies suppied with the MX-4845A/SRA- 34(V). The ony connection required between the MX-4845A/SRA-34 (V.) and the RF switching group is the RF transmission ine. Transmitter Adapter MX-4847B/SRA-34 (V) adapts the contro circuits of various radio transmitters to the dipex antenna couper contro system. Compatibiity with the AN/WRT-2, AN/URC-32, AN/SRT.. 15, Or the AN/URT-23 is achieved by use of one of the jumper pug assembies suppied with the MX-4847B/SRA-34 (V). The ony connection required between MX- 4847B/SRA-34 (V) and the RF switching group is the RF transmission ine. The RF switching group functions as an RF switching matrix between radio transmitters, and/or receivers and antenna coupers empoying dipex contro. Eectrica Equipment Cabinet CY -4033/SRA-34 (V) contains provisions for one to four RF Switching Units SA-1070/SRA- 34 (V). A maximum of 20 RF sources may be connected to a maximum of 25 oads on a 1-for- 1 basis. One RF switching unit is required for every five RF sources. The RF switching group may be controed ocay (manuay) or remotey. Remote contro requires the use of one or more Remote Switching Contro C-4787/ SRA-34 (V) units. The CY -4033/SRA-34 (V) contains a water-cooed heat exchanger which permits interna cosed-cyce air cooing. The remote switching contro C-4787/SRA- 34(V) is a remote contro unit for the RF switching group. t may be ocated up to 900 feet from the CY-4033/SRA-34 (V). One SA-1070/ SRA-34 (V) is controed by each remote switching contro unit. Each SA-1070/SRA-34 (V) requires a C-4787 /SRA-34 (V) for 'remote contro operation. GROUP OA-4794A.-. Antenna couper group OA-4794 consists of four antenna coupers CU-1169/SRC-16 mounted in eectrica equipment cabinet CY -4032A as stated previousy. This couper group (fig. 6-19) may be used with an automatic receiver-transmitter such as Radio Set AN/SRC-23A (V), or with manua equipment and the appropriate adapter. Each of the antenna coupers mounted in Eectrica Equipment Cabinet CY -4032A/SRA- 34 (V) has its own RF input, but a four are connected to a common antenna. The antenna couper bandpass permits RF output from any one, or up to eight, of the antenna coupers to a common antenna. (Outputs from two adjacent antenna couper groups operating in the same frequency band may be connected together.) f more than one transmitter is transmitting at the same time, the frequencies must differ by at east 5 percent. The necessary contro information is transferred between the transmitter-receiver and the antenna couper by a sequence of ow-power puses dipexed on the RF ine. Since there are four antenna coupers invoved, each requires its own contro,circuits. Each antenna couper, therefore, has its own dipex subassembies that consist of a ow-pass fiter assemby, a couper eectronic gate, and an eectronic digita counter. n addition to the dipex subassembies, a pair of antenna coupers shares a sequentia timer card and a power suppy modue. The four antenna coupers share a common therma aarm contro. The circuits of Eectrica Equipment Cabinet and the four antenna coupers are cooed by an interna cosed-cyce cooing system empoying a water - cooed heat exchanger. n the event of excessive temperatures, aarm signas are generated that ight the aarm indicators on the ow er pane ofthe eectrica equipment cabinet (fig. 6-19}. Each of the four antenna coupers requires its own dipex circuits for operation. These circuits incude a ow-pass fiter, an eectronic digita counter, a coup)!r eectronic gate, one circuit of a sequentia timer, and an input to the therma aarm contro as shown by the functiona bock diagram in figure Contro information is transferred by a sequence of ow-power puses dipexed on the RF ine. This sequence of puses is repeated continuousy as ong as the equipment is energied. The first puse is a synchroniation puse and is twice the duration of the remaining puses. This puse is detected in the couper eectronic gate, and the information is used to reset fip-fops in the eectronic digita counter. Each of seven contro puses is preceded by a cock puse. The cock puse is detected in the couper eectronic gate, and this information steps fip-fops in the eectronic digita counter to provide the proper enabe puses. The contro puses carry binary information; that is, they are each either on or off, indicating, for exampe, operate or standby. 165

3 ELECTRONCS TECHNCAN 3 & 2 VOL. 1 ELECTRCAL EQUPMENT CABNET CY-4032/SRC-34{V) Figure Antenna couper group OA-4794A/SRA-34(V) (162A) The couper eectronic gate has circuits for detecting and generating the various contro puses, The synchroniing puse is detected, and the sync output is s.ent to the eectronic digita counter to reset the fip-fops. The cock puses are detected and sent to the eectronic digita counter to trigger the fip-fops. The contro puses from the transmitter-receiver are detected and ANDed with enabe puses to contro the antenna couper. The contro signas from the antenna coupers are ANDed with the enabe puses from the eectronic digita counter and then appied to the R F ine to contro the transmitter-receiver. The sequentia timer card contains two identica circuits. Each antenna couper uses one circuit; therefore, two antennas coupers share the same card. f a couper is receiver 166

4 Chapter 6-CW AND VOCE COMMUNCATON SYSTEMS NO. TRANSMTTER LOW PA SS FLTER AA ELECTRONC AAB ELECTRONC DGTAL AA7 CONTROL LNES A2 SEQUENTAL TMER AA9 NO.2 TRANSMTTER..N PASS FLTER AA2 ELECTRONC AAO ELECTRONC DGTAL AA CONTROL LNES A3 ALARM NDCATORS 1-- AND CONTROLS THERMAL ALARM CONTROL AA19 TO NO.3 TRANSMTTER LOW PASS FLTER AA3 ELECTRONC AA3 ELECTRONC DGTAL AA2 CONTROL LNES A4 r SEQUENTAL TMER AA14 NO. 4 TRANSMTTER LOW PASS FLTER AA4 ELECTRONC AA5 : ELECTRONC DGTAL AA& CONTROL LNES A (162A) Figure Antenna couper group OA-4794A/SRA-34(V} functiona bock diagram. tuned, the circuit provides a continuous operate signa (ground) to the antenna couper for 30 seconds after the receiver tune and operate signas are removed by the transmitter-receiver. This 30-second extension of the operate signa is provided to permit switching the RF ine (and dipexed contro information) from the transmitter to the receiver. The therma aarm contro receives a warning temperature ground from a therma switch at the rear of the cabinet and aarm signas from a four antenna coupers. The warning signa energies warning indicators, sounds a horn, and enabes the UNSAFE temperature aarm gate for aarm signas coming from the antenna coupers. An aarm signa from any 167

5 ELECTRONCS TECHNCAN 3 & 2 VOL. 1 antenna couper accompanied by the warning temperature ground wi ight the UNSAFE temperature indicator and cause an aarm signa to be sent to the transmitter-receiver feeding that antenna couper. The transmitter is paced in standby, and the antenna couper aarm indicator is it. n the therma aarm contro, there is a horn disabe circuit operated by the HORN CANCEL button on the front pane and an emergency operation circuit caed batte short enabe. This circuit can be operated by the BATTLE SHORT button on the front pane. The ow-pass fiters (fig. 6-20) provide access to the RF transmission ines for the acceptance or appication of the puse train. They aso provide ow-frequency isoation so that the puse train signas wi not be oaded excessivey by the antenna couper inputs. A radio frequency ine fiter (not shown) suppresses RF interference in the cabinet primary power input. A separate fiter is provided within the subassemby for each primary power ead. The power suppies (not shown) provide reguated 29 vots to the couper eectronic gates, eectronic digita counters, and sequentia timers. They aso provide unreguated 28 vots to the therma aarm contro. UHF MULTS UHF muticoupers are usuay used for transceiving. This and the cose channe spacing desired during operation require mutipe-resonator fiters to achieve the necessary isoation between channes. n a cases, coaxia cavity resonators are used. UHF muticoupers are designed for use with antennas whose VSWR is 2:1 or ess throughout the operating frequency range of the muticoupers. Two UHF muticoupers argey used in the feet are the CU- 691/U and the AN/SRA-33. Antenna Couper CU-691/U Antenna Couper CU-691/U (fig. 6-21) provides isoation between four transmitter and/or receiver combinations operating simutaneousy into a common antenna. soation is achieved with four highy seective tandem fiters and a combining network. The high seectivity reduces intermoduation interference, cross moduation interference, and spurious responses. Harmonic radiation from the transmitter(s) is aso attenuated Figure Antenna couper CU-691/U. GENERAL DESCRPTON.-nside the couper are eight siver-pated auminum tunabe cavities. When propery tuned, each cavity is a 1/4-waveength shorted coaxia eement. The cavities are aperture couped in groups of two, forming four dua-cavity tunabe tandem fiters. Adjustabe tuning sugs in the cavity side was permit compensation for minor irreguarities in the cavity resonance curve. The outputs of the four fiters are couped to a common june tion at the input of a combining network. The output of the combining network is the output connector for the antenna transmission ine. The couper is capabe of accepting RF energy on a input channes simutaneousy, each channe having a carrier power eve of 200 watts. A monitor couper assemby is inserted in each input transmission ine between the input type N coaxia connector and the input to the tandem fiter. The couper assemby deveops d.c. votages proportiona to the forward and refected wave components existing on each ine. The d.c. votages are suppied to the meter 168