KNOBS-GenRad_Experimenter_May_1948 电路图.pdf

《KNOBS-GenRad_Experimenter_May_1948 电路图.pdf》由会员分享，可在线阅读，更多相关《KNOBS-GenRad_Experimenter_May_1948 电路图.pdf（8页珍藏版）》请在收音机爱好者资料库上搜索。

1、z: l- e . - - e . e co: l- V) = Q z: co: . :z: I- Q z: e V) I- :z: . :IE . co: = V) e . :IE PEBIMENTEB Radio . M . A VOLTAGE MULTIPLIER FOR THE VACUUM-TUBE VOLTMETER IN T HIS ISS U E Nt:w STANDARD PAItThi . WIT! FIXED Bllm;!J St:rn1lo. Page 2 . 7 eA 10:1 VOLTAGE MULTIPLIER is now availlhll to ext cu

2、d the ntl( of voltage mcnlllttlllcn of the TnE tSOOA Vacuum-Tube Voltmoter to a ll1!lxilllUIll of 1500 volt,:;, This multiplier is a capaeitive voltage divider which provides a 10:1 rcductioll bel ween the volttgc applicd to the Illulti- plier and the voltage appcating aCIO!l;1; the voltmctol tCl1l1

3、innls. The mult piiel EnWS on to the end of the voltmeter probe, adding !lbout. t.wo inches to its length. Since the input capacitances of the voltmeters difTel slightly, an (1101 in multiplier ratio of 2% is pOlsiblc. but an adjustment. is PIO- vided by IllCrulS of which the ratio can be.adjusted t

4、o l% for any TYlE l800-.o Vacuum-Tube OltlllctN. When a multiplier and a. oltmcter are ordered together, this adju:.lmcnt is made at the f:lctory. The CfFCf:lllC J.?rtlJlcJ iNput rcsist:mcc of thc muJ1jpJjT j: . of 1nl onJrr of tOO times that of the voltmeter probe alone, and the effective parallel

5、capacitallce is 1.5 p.p.f. When the cap and center plug arc lIsed, npproximateiy 0.5 /J/Jf i added. The n:SOIl/lIt fr0- quencyof t he probe, 1050 Me, is not changed by the acl- Figu.e I. Exploded ylew of pobe, mltlpll , and (p. IET LABS, Inc in the GenRad tradition 534 Main Street, Westbury, NY 1159

6、0 TEL: (516) 334-5959 (800) 899-8438 FAX: (516) 334-5988 RadioFans.CN 收音机爱 好者资料库 GENERAL RADIO EXPERIMENTER . - 6 0 n . , OIIUe 0; c. fig . 2. Piol of low.f,. quency . rror 10. Ih. Typt II00-P2 M . lllpU . Th. hi . q . ncy correctlOl lor Ihe ,.oltm.I II unchole-d by Ih. oddillol of lite mumpli . , d

7、itioll of thc multiplier. Thc multiplier frequency error iii plott.d ill Figure 2. The multiplier is not rc.ommended for use at frequcncies below 100 kc. SPECIFICA liONS Multiplier Itau, 10 to l. Dlmenllontl (Length) 2 ll (diameter) H ineh($, over-all. N. , WeIgh 4 OUtlCCll. Typ PM 00-P2 Multlpll. ,

8、 $1.00 NEW STANDARD PARTS Ill !lCW look that hM lalely been cvidfnt on GUlIe.ml Radio inatrumentll reflects the improement in appc!Ullncc of our ftandtlrd parts. Defigncd to lx altr:lclivc tl.! well as useful, th(!f knobs and diuls arc 3lso aailabtc separately to those who make their own lahor:ltory

9、 quipment. KNOBS TnB 1:1 Knobs, which rtplul.:e the TYJE ()37 series, nrc uniform in bCne.ul llppCllrance and application and wen: d igned primarily for use 011 Genoml Badio instruments. All arc simillUly fluted llIld have matching uarrow skirt;, so that a unity of design is achic(l when different t

10、ypes are used on the SRme pane. Pointcr model . 11Iwe InrbC white ,-f!hapcd iJldicators for good vi;i- bility, KNB_l KNB-2 lvo IlCW typcs are now available, the bar 100obs, KNB-l ami KNB-2, which are c:;pceiully cOlleniellt for Ule on rOlal) switches, :Uld the spin- ner knob, J(NU-3, for r:tpid rota

11、tion of the control sbaft. 011 slow motion drives. Each 1000b is made of blfLek phenolic rc:;in with a molded-in brass inert, and is fitted with two !Octscrcws, 00 apart, which are thCIl(k-d thlough the metal insert. The boring of t he shaft hole is performed us a Hllal operation on II pre- cision m

12、achine, csJlccially set tip for the purpose, so as to insure an accurately sied hole which il concentric with and perpendicular to the molded portion. Holes arc bored to fit a Jfi-ineh diameter shaft and arc equipped with removnblc bUl-ineh diameter shafts, l -INCH DIAMETER-WITH BAR Net Weight Packa

13、ge Package Ty for 6 Code Word oj 6 of ro ItN_1 13% o.)liANOUON:1 $3.S0! $13.00 1 I-INCH DIAMETER -WITH BAR Net lIeigll/ Ilckage Pocko(Je .-. Type for , Code II ord of fi of 20 KNI-2 1 6 o. IIIAIIKNOUTWO! $3,7S $14.00 IET LABS, Inc in the GenRad tradition 534 Main Street, Westbury, NY 11590 TEL: (516

14、) 334-5959 (800) 899-8438 FAX: (516) 334-5988 RadioFans.CN 收音机爱 好者资料库 , 2-INCH DIAMETER Nel Weight Package Package Type jor 5 Code Word oJ.5 0/ 0 KNSP. I. 0%. INUHLsollAn: I $4.2,1 $16.00 2-INCH DIAMETER -WITH SPINNER N. Type Weight Code Word 13/s-INCH DIAMETER Unit Price $3.00 Net Weight p(lcJ,:age

15、 /uckagc Type lor /j Code Ward of fj of f!O I(N5P.615h OE.)NUULNOliSIX I $3.001 $11.00 2%-INCH DIAMETER Net Weight Package Package Type for Ii Cf)I/c Word oj 5 of f!() KNSP-l01,2v o.!SuIlLsolln:;!U.50$21.00 r 2%-INCH DIAMETER-WITHOUT POINTER Nel Weight Type for .5 Code IV ord Package Pack(lgIJ oj 0/

16、20 KNS.12il7oz.j XUI!LNOBDOZ. 1$5.75/ $22.00 The TnE KN Fluted Jnobs fire shown 111- prol(imatcly one-hnlf actual size in the Blustr:l- tion. MAY, 1948 KNSP-8 ZKNU-3 KNSP-l0 KNS-12 KNOB AND DIAL ASSEMBLIES .- new line of photo-;tchcd dial; with frostcd-ehrome surfaces Ieplac(s the oldcr nickel-silve

17、r ll1odel. The nEs 001, 002, and 90f dials are ayailable with 01 without friction drives anci in two or morc scale lellp:f.hii. Thc:11ed for applicat ions requiring simple, dirc(.1. shaft positioning of mod- erate preeision. Dials arc lU;semblc1 on standard TYPE KN k-nobs and therefore r .mount on t

18、he salllC size of shaft. The punched brass dial is accurately located 011 the knob hy bu,ps, frOIll whi(h the iihaft hole is (OIINlltrieay bored, and is al.o insubted from the shaft insert by the phcllolic material of the kHOh. Each dial is photo-ctchcd and fin- ihed with blaek liups on a fro.W etch

19、ed dial is :;atisfactory, bu! when settings must be made more precisely than can be dOlle with a direct drive. Tho speed-reducing drive grips the rim of a separate disc behind the dial, so that the dial sUIface is not marred, and the driving Shtlft is mounted on the panel in an ect:onidc bushing whi

20、ch per- mits later:llndjuslmcnt to the smoothest operating position. N. Cod, Type An Dilluio1ll Dritoe lIeilllil Word Price 901.HO , . 00 . Direct. 2 o . 1111.00 $2.7S 901JD 270 . Olloct 2 Oil . 1)!I1 2.75 901-LD 3600 Din.l:t 20t. D!LID 2.7S 2=V4-INCH DIAMETER -TYPE 902 DIALS 902.HD IIO . Direct 211

21、1 oz. IlUIAI $2.75 902_JD 270 . DireUIIIl 2.75 902_HF 110 . FrirtiOIl, 3.3:1 4 oz . 1)1)1011 3.75 902. JF 270 . lrictiOIl. 3.3:1 4 oz . OI.IUO 3.75 4-INCH DIAMETER -TYPE 904 DIALS 904.HO I 110 0 . Direct. 5 oz . mrAU $3.25 904 JO 270 2 . Dirort 5 oz. 1)1101) 3.25 904_H 110 . Friction, 5:1 80t. IHt:N

22、 4.25 904.J 270 2 Friction, 5:1 8 oz. IlIrUT 4.25 FRICTION-DRIVE PRECISION DIALS 1 II; tlo:) :Iud 6 Pt(tiion Dial! 1fpl:Itf tilt ilIES iQ.1 and i06. They han finc black linN xl1ctly I)()!nj.;laing IUa Ihin., on a frO-tro-cilromc backgrolilld. The palin of Ihe lin(s is (hOOn to give h. tnllxinHlI1l a

23、ccuracy of (tting (on :,j . l(,lIt with readability. Earh dilll has a lathe-turned rim 0 ill:uJC cOlleentricity, lind is :lttachcd to a machined ura;: hub, which i f:U;tclIcd to the shaft by two !et:-CNw:-, :leee:si- hlc from the rront of till dial. The frictioll drivc, which is fully adju;,tahlp, o

24、perates on the outer edbC of a horse- Sh()(,lfl.ped lot in the di:.I, so that the SIOW-SpNXI knob turnfl in the nULe dircction as thc dinl :nd P-O that the (lJjvc mcchuniSlll al comes within the dinl proper. 4-INCH DIAMETER -TYPE 90S PRECISION DIALS 905HF 110 I 2 . I r:rklion, 6:1 I !l O. nll!l.G $1

25、0.00 905.JF 270 lriClion, 6:1 o o . 1)1111)1 10.00 6.INCH DIAMETER -TYPE 906 PRECISION DIALS 906-H 110 . Frietion, 8:1 15 oz. IlIIiOT $12.00 906J 270 FrictiOil,8:1 15 oz . 1)11lA 12,00 .-., IET LABS, Inc in the GenRad tradition 534 Main Street, Westbury, NY 11590 TEL: (516) 334-5959 (800) 899-8438 F

26、AX: (516) 334-5988 , MAY, 19 IET LABS, Inc in the GenRad tradition 534 Main Street, Westbury, NY 11590 TEL: (516) 334-5959 (800) 899-8438 FAX: (516) 334-5988 GENERA.l RA.DIO EXPERIMENTER GEARDRIVE PRECISION DIALS Two (ntiNly new unils, thc TnES !lO7 rwd 008 GC:lr-Drive llci,.ioll Dinl!, Wtn dc:;igll

27、d ror the Illo.:ilivc. fixcdrHtio reduction thivt. The diul if funlhld in fro.Rttd chrome piatt with contra.!tin btwk lin(!I, ami itl! hub is uttached directly to thC ,.hnft by two scU;creW!l. TIl( ppM ha.l internal letth, 0 that th knoh, driving I stainlc:S !;tC1 pinioll, turll in thc same directio

28、n us til( dilli. Thc pinioll ill held in a collet ill the knob o thal it Itlay be readily adjusted to projtc:t throuV;h :my panel, up to 16 indl IhitknCR, by simply looflclling thl: ttCI(i! in tbe knoh. This driw us- scmbl) rllJll! in a floating bronzf bUllhillg that i:; !lpring guidttl to hold the

29、gearll in propel IlIC!r wil hout backla:,;h and that abo olwilllt; Ow nt( for preci( pallfl drillin. The pinion IUlti I-Iltlr h:t! h are (tip! ciully dcsigned 10 nw lIIoothly tugether rlml are cut on a prcc:iI:ion P;(ll! shlllK1 to insure uniformity, The 10:1 nitio PCl11lil1l cnlibrating t h( J.l1ob

30、 as:t crni(r, The frontfpall(1 a.fcmbly require!: onl . two G-32 pnne hole,; for mounting, sod the I:uge holes for the window and drh-e of the bnek-of-pnocl model art round. so tha! they tnll be readily put in with :l. punch, holo-fllW, or flycutttl. The ant i-pflnlllnx floating indicator i !:!uppli

31、cd with Il. dullbluck billkup plate, which fills the window on the back-of-pan(1 I yP(,! 4-INCH DIAMETER GEARDRIVE PRECISION DIALS 0pl _ (jear 7yPf!._ _I?.unti Arc J)itUWM J)rilRatio 907.LA front.of.ponet -3600-1-360-1 10:1 Nrl Wright 11 907.LI I lock.of.ponel 3600 360 lOll 6-INCH DIAMETER GEARDRIVE

32、 PRECISION DIALS 901LA 1 f.ontof.panel 1 3600 360 1 lOll 901.LI lock.of.panel 3600 360 1011 II oz. 1 21 oz. 10 ox. Code JI fOr obtaining ml) required volt- age within their mnbe, quickly, rOIl- venienti) :lnd efficiently. Variac volt- age output is Hlbstulllially independent of load current, as (ont

33、rasted with re- sistive controls. Usually, :1Ila05 :rO fre- quently adjustrcl to meet changing rcquirelllcnts of speed, illumillfltioJl, 1100 voitag(, etc. Occu.;ion:llly, Vnrincs urc required to aci ilS fixed uutotmllsfornlcrs, a !;clvi(:c for which lile latter arc more properly suited. UncleI thes

34、e conditions, the Vnrine l)Ill;h srtting remains fixed for long periods undtI load, and the t.lIrllR nncle! I he bmsh arc Ibj.dcd to pro- longed Olxrat ion at high temperature. At this point a brief discw!sioll of the hmction of and need for carboll (adufilly :l. midulC of carbon, gmphit.c, nnd, som

35、etimcs, metal) brushes in V:triaes i!l ill oldcl. The olu$h is lhe scrret of successful Ynriac design, To pennit adjustmcnt (i.e., switching) undcr load ilhoul interruption of current, the contacting devicc 1I1l1st est.ablish COllt act with Illl adjacent t.m!l of wire before breaking the (!onttlct a

36、lready estab- lished. This means that the contacting device IUlIst, perforce, sholt citcuit. one or more lull1! in celtain positions. In order to limit. the short-circuit C UtTent. to a fl;afe and reasonable vttlue, the con- tact must huve It certuin minimum rcsitaIH.c. Since this resist.uIH.:e is t

37、lllV- ersed by the load current as well as by short cilcuit. CUIIlJlltS. it mllst not be too high. In effect, we have a tug-of-war hct.ween shOlt-ircuil losses, which call for fI high rcsistance, find load loss0!, which call for a low tclist,lillcc. The compromi;:e ig best effected ,hell the two los

38、ses atO equal. CarbOllaccow! Illatrliuls meet j bc resistance rcquire- mentH niedy and h:lve lubricating ali(I wear harlletoris-tics lh:t :IC excellent lignins! tlte copper ulfuc( of the cx- IXlse:1 brul$h ttuck. BccalliC of the load losses wh ieh arc unavoidably iutrodllce1 by the brush lqlljremcll

39、t, the hottest spot on a Valiac will nlways be dilCctiy under the brush. This localized hent ;:otlroo is ill addition to the uHirollllly distributed hettting of core and coppel losscs. These laUer arc muint!liued at cOllscnative levels in VUliac design, but the brush heat, even with bCJlCIOUS heat f

40、fldiatol plOvisions, if. still sufficient 10 raise t.he tempe/,ature of the turns ill thc inlltlcdi- ate vicinity of the brush to tl point where thc btue copper oxidizcs rnpidly. Copper oxide, uTlfort,unately, is a poor clectriCftl condlctor, and its fOIlHalion in the vicinity of the b/ush further i

41、n- C!,(,:lSlS the brush heating undcr 10:ld, Thu! heat IC:l(ls to oxide which lead, to marC hcn!. in fill cxtrcllwly vicions cilcle, H fnilulC is to be avoided, the citc1e lllUSt. be broken. Two good method . llfle so fnr been found 1.0 plCvent oxide accumulatioil. One is obvious. Keep the brush tmc

42、k clcan, using the fine crocus cloth nnd rtlrbon tetnlchlQlide clcaning tcclmique outlined in the Vnriac instruction shL-Ct., 3t. frequelll (semi-weekly) intcrwls. The other is to )lCvcni or slow down oxidation by excluding air from the vicinity of the brush by the pplictllion of a thin layer of hea

43、t. ICsist:.Ult, inert grease to the brush tra:k. Dow-Coming D-C-4-1 Silicone Grease ha.s been found to be excellent. for this purpo:;e. A COnl- bination of the two methods,;l thorough cleaning llnd lcgtca.singcery two weeks, will pctmit indefinit.e opelntion of Vari- !l.cs with fixfd Iwush setling.

44、-GII,D,nI SMILEY IET LABS, Inc in the GenRad tradition 534 Main Street, Westbury, NY 11590 TEL: (516) 334-5959 (800) 899-8438 FAX: (516) 334-5988 GENERAL RADIO EXPERIMENTER HONORS-Awarded to Melville East- ham, Chief Engineer and former Presi- dent of tbe General Radio Company, the 1948 New Englund

45、Award, at the anlluul meeting of the Enginccring Socicties of New England, at Boston, April 29. A scroll of illuminated parchment suitably inscribed, the New England Award is given each year to a living engineer, resident in New England, who, by out- standing achievement, shall merit reeog- !lition

46、of his accomplished work as well u.s of his character, by his fellow en- gineers of New England. RECENT VISITORS- From Poland: Przemyslaw, J. Jaros, Gencral Superintendent of Communica- lions, Polish State Railways, Warsaw. From Brazil: Captain Aldo V. da Rosa, Chief of Technical OiisioIl, Brazilian

47、 Air Forcc. From Chile: William Feick, Professor of Communication Engineering, Univer- sidad Tecnica Federico Santa l1aria, Valparaiso. From Holland: :1r. O. Goodhart and Mr. W. Y. Storm of N. V. Philips Tele- commlllication Industries, Hilversum. M,lvlll Eastham. PAPERS prcscnted at the 1. R. E. Na

48、- tional COJlvcntion, New York, lfarch 21-24, 1948-by If. B. Hichmond, Chairman of the Board, An Enginccr in the Electronics fndustr) -Prospects, Preparation, Pay; by W. N. Tuttle, Engineer, Use of Diode Rectifiers with Adjustable Transfonncrs for Motor Speed Control; by R. F. Field, En- gineer, Losses in Air-Cored Induc- tors; by J. K. Clapp, Engineer, Fre- quency Measurement by Sliding 1 far- monics. GENERAL RADIO COMPANY 215 MASSACHUSETTS AVENUE CAN.RIDGE 39 MASSACHUSETTS IlEW YGU ., IlEW YGU . WElT stlUT TU.-WOITII Iun TELEPHONE: TROWBRIDGE HOO BRANCH ENGINE