US2666183A

US2666183A - Variable attenuator

Info

Publication number: US2666183A
Application number: US314804A
Authority: US
Inventors: Frank J Ocnaschek
Original assignee: Collins Radio Co
Current assignee: Collins Radio Co
Priority date: 1952-10-15
Filing date: 1952-10-15
Publication date: 1954-01-12
Anticipated expiration: 1971-01-12

Description

Filed Oct. 15, 1952 INVENTOR. /kA/wr Owens-avril Jan. l2, 1954 QN l NM. Q BM. .WN N N NM. @www DN l QN @uw NN a. www NN m 7 7 /f 7 /r ,NN u f. 0N NN ,WN .WN W7 www `7 J NN WN NN NN NN m. NM. QM NM.

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Patented Jan. 12, 1954 2,65*@183 VARIABLE .A1-mueres Frank J. 0cnascl1ekDallas, Tex.; assignorV to ,Hollins` Radio `(lolurlpany, Cedar i Rapids;v Iow'a',

e qrpereiieiwf Application lOctotb'ear 1952, Serial No. 314,804

Thisrinvention relates to-a variable attenuator material 29. A resistor 3i! has one side conf- Whereinthe-impedance'mayibevaried-toprovde nectedtothe inner conductor 28. A lead-31' is a change in coupling.` connected to the other sideV of resistor `Sliffarid jltis? oftentimes desirable to lattenuate .a high, to a second'capacitor disc 3 l.

ultra-high, or very high Afri-o uency signal to ai 5 A'fourth resistor 32 has one end connected toA fraction'of its-value; "At other times it desir.- the disc 3| by a lead 38 and its opposite endA able to match ,mpedancesso that the ,most attached to the memberf23 by solder material 33;:

eilcient utilization of power ma?! bev Obtaind: vAtapered threaded portion? 34' is attach'edto, =It`isanobiectof this invention, therefore, Lto the cylinder it and a tapered threadedcollar: DIOI@ 'a--Vlable llmlatOr and COlllllrlg .der 10 35-is received' thereon'so as to clamp the mem`` vicevvhereintheamountzof coupling and imned: ber `23 to the member 34. The internal threads.v ance maybevariedatwill. of the collar 35 aretapered .opposite fto .thetap'er, feature -of this invention is found in. the of the threads oimember `Bil.4 When the collarv provision `for afgenerally .cylindrical ,cal/{ty'QS 351s loosened Ythe member .23 may be rotated or onatorwhichhas mounted/atopposterends input 15 slid relative to cylinder lll by suitablelevers `36. lines-:connected to capacitor .plates :by a .pair G` When the collar .35:is tightened, vthemember leadsfsoastoiform ,an 4inchlctive coupling. 23 is rigidly held and cannot .be rotated.A

Further -features, objects and Jadriftrlilfties will FigureiZ illustrates schematically .the appaandclaimsfwhenreadin `view of `the,f-lfftivlfles z 20 thrcapacitor fplates 2i! and n:il are1c,anacitively n-which; i couplefipto .eachother andinductances L1 and La Figure risasectioual viewloifthefvatebe 'etareinductively .coupledtoeach Qthtr- The i11- nuator of this. invention, .and` 4 dutance L1 is the loop comprisinathe leadsll. Egurez isa .schematic `vievv illustrating the and,38;and3platec31. ,The indugtange-11aj5-Aghe electrical equivalents of the circuit. 25 loopeformedphy:the leads39 and 34,9 and the,

Figure ALillus'trates a `hollovv conducting .Cyl' plate-2.0'-

inder l0 whhi-hasrmounttd in 011e end thereof Theacoupliue 4between the capacitive Plates an internal conducting plug ll- It iS fastened loa-nd .lpmav be varied `by,Ilflovrl.themerigir tothemember lo by set' screws i2 or other tudi-nally 4relativetoeach other, ,frhiskmaynbe uoiingiiieans. .aecomolishe,dlov` loosening the .sleeve mand member H` and' a portion lli enlarged and 36. Thisallpws .coarse ,adjustmentof the co threaded. A coaxial cable connector 45N 1S plingbetyveen theinputand, ontputsioles .Minor threadedly 'received/Q in the portion I 4 andy termladjustments, mayfhe ,mdefbr 1 meting l Wel-mem, nanas in an outer conductor I5 and an inner ber 23 relative to the member" I' so that 'the conductor Il. The inner and outer conductors 3v coupling loops comprising L1 and L2 rotate relare insulated from each other by insulation maative to each other so that the coupling is varied terial I8. The outer conductor i6 is electrically from a maximum to a minimum Value. This connected t0 the Conducting DOTOH H but the allows ne adjustments to be made :at these inner conductor I7 is insulated therefrom. frequengiea A resistor I9 has one side electrically connected Llo other advantages that are obtainable with to one end of the inner conductor l1 and its this structure are; opposite end is connected to a lead 39 which 1s 1, can be used over a large frequency range, connected to a rst capacitive plate 20. A sechigh frequency, very high frequency and ultra ond resistor 2| is connected to a lead it which high frequency. is connected to the plate 2li. The other side 45 2. Very low standing wave ratio.

of resistor 2| is connected to the plate I by 3. Provides same attenuation over Wide fresolder material. quency ranges.

The opposite end of the cylinder l0 re'lves 4. Will withstand severe conditions of shock therein a second plug 23 of conducting material and Vibration which is formed with a central Opening 24 and 50 5. Longitudinal movement provides coarse conwhich has a threaded portion 25 in which a trol, and rotational movement provides fine second coaxial connector 26 is received. control.

The outer conductor 21 of the connector 2t is 6. Can be used as an impedance transformer connected to the member 23, whereas the inner as well as an attenuator by changing the values conductor 28 is insulated from it by insulation 55 of resistance in either end of attenuator.

goodies 7. Can be inserted anywhere in transmission line.

8. Has no tuned elements, therefore does not require tuning and is very stable with respect to frequency temperature and humidity changes.

9. Provides a common conductor.

10. Can be used in a balanced circuit by suitable changes in circuit arrangement.

It is seen that this invention provides a variable attenuator or impedance transformer which may be very accurately adjusted.

Although this invention has been described with respect to a particular embodiment thereof, it is not to be so limited as changes and modications may be made therein which are within the full intended scope of the invention, as defined by the appended claims.

I claim:

1. A variable impedance and coupling device comprising, a hollow conducting cylindrical member, aflrst internal conducting plug received within one end of said cylinder, said first plug formed with an axial opening, a first coaxial connector connected to said first plug, a rst resistor mounted within the axial opening of said first plug and connected to the center conductor of said coaxial cable connector, `a first capacitive plate attached to the opposite side of said first resistor, a second resistor with one end attached to said rst plug and the opposite end connected to said rst capacitive plate, a second plug rotatably and slidably supported in said cylinder and formed with an axial opening, a third resistor mounted within the axial opening of said second plug, `a second capacitive plate attached to one side of the third resistor, a second coaxial connector connected to said second plug, and a fourth resistor connected between said second plug and said second capacitive plate.

2. A variable coupling and impedance matching device comprising, a hollow cylindrical member, a first plug formed with a central longitudinal opening mounted in one end of said cylindrical member, a first resistor mounted in said longitudinal opening, a coaxial connector connected to said first plug and its center conductor connected to one side of said resistor, a first capacitive disc connected to the other side of the first resistor, a second resistor connected between said first capacitive disc and said first plug, a second plug slidably and rotatably received in said cylindrical member, a second coaxial connector connected to said second plug, said second plug formed with a longitudinal opening. a third resistor mounted in said longi tudinal opening with one lead connected to the center conductor of said coaxial connector, a second capacitive plate attached to the other lead of said third resistor, a fourth resistor connected between the second plug and the second capacitive plate, and a lever attached to said second plug for rotating and moving it longitudinally relative to said cylindrical member.

3. A variable attentuator and coupling device comprising, a. hollow conducting cylindrical member, a pair of plugs mounted in opposite ends of said cylindrical member, said plugs formed with longitudinal openings therethrough, a pair of coaxial connectors mounted, respectively, to said plugs, a rst resistor formed with a pair of relatively rigid leads extending from opposite ends thereof, one of the leads of said first resistor connected to a first capacitive disc, said first resistor mounted in the longitudinal opening of the first plug and the opposite lead of said first Vresistor connected to the center conductor of the first coaxial connector, a second resistor formed with a pair of relatively rigid leads with one of the leads connected to the first plug and the other lead connected to said first capacitive disc, a third resistor mounted in the longitudinal opening of the second plug and having a pair of relatively rigid leads, a second capacitive plate connected to one of said leads of the third resistor, the other of said leads of the third resistor attached to the center conductor of the second coaxial connector, a fourth resistor with relatively rigid leads, one of its leads connected to the second plug and the other lead connected to the second capacitive plate. and Yfastening means for loosening and tightening the second plug relative to said cylindrical member.

4. Apparatus according to claim 3 wherein said fastening means comprises a tapered threaded portion on one end of said cylindrical member, and an internally threaded tapered collar receivable on said rst tapered portion.

FRANK J. OCNASCHEK.

References cited in the fue of thispatent UNITED STATES PATENTS Number Name Date 1,888,278 MacDonald Nov. 22, 1932 2,422,601 Tashjian June 17, 1947 2,494,722 Rosen Jan.'17, 1950 2,514,544 Hansen V July 11', 1950 2,561,184 Dehn July 17, 1951V