Rohde & schwartzFAM 电路图.pdf

MODULATION ANALYZERS Characteristics, uses The Modulation Analyzer FAM otters a maximum of con. venience for modulation measurements on AM, FM and phase-modulated signals. All tunctions being microproc- essor-controlled, manual operation is reduced to aminimum. Modulation measurements over a range of carrier frequen- cies from 55 kHz to 1360 MHz are performed more precisely end more easlly with the FAM than with previously available equipment. The lEG-bus interface makes the instrument system-compatible end suitable tor use in automated test assembties. Types 01 measurements The Modulation Analyzer can be used tor measurements otherwise calling tor up to five differ- ent instruments. It features the following capabilities: . Measurement of modulation depth, frequency deviation and phase deviation . Simultaneous carrier-frequency measurement with 1 Hz or 10 Hz resolution . Measurement of modulation frequency with 0.1 Hz reso- lution . Distortion measurement down to <0.1 %, also SINAD indication in dB . AF vo/tage measurement with weighting filters (psophometer function) . Evaluation of external AF signals Unwanted modulation can be measured and weighted accu- ratelyon account of switch-selected test bandwidths and standard weighting filters. Fjeld of appllcation The basic model covers a carrier- frequency range of 55 kHz to 120 MHz and offers a very economical and high-performance solution tor measuring tasks in FM and AM broadcasting and certaln radiotelephony 254 and other radio services. analyzers The Frequency-range Extension Option - which can be retrofitted - extends the frequency range up to 1360 MHz, thus covering practically all radio services. Special features The FAM exhibits negligible inherent noise and excellent linearity. Residual FM being less than 1 Hz in the basic frequency range (proportionally increasing above) with CCITT weight- ing and 5 Hz with 20 kHz weighting bandwidth, whilst residual AM is as low as 0.01 %. the FAM perrnits unwanted modula- tion to be measured precisely. The FM stereo noise of FAM model 54, being -72 dB referred to 40 kHz deviation, CCIR weightlng, permits precise SI N-ratlo rneasurements, say, on FM broadcast transmitters. The transmission IInearity of the FAM fulfils the exacting demands involved in wideband modulation methods used. tor example, in FM broadcasting. Excellent amplitude and phase linearity make distortion-free demodulation of multi- plex signals possible; see application example on page after next. Dlstortlon of less than 0.1% and stereo channel separation of 50 dB guarantee accurate results of measurement. Democ*Jiat8d stereoaignal av8l8*M FMoI ModIMaon AnaIyzer FAM RadioFans.CN 收音机爱 好者资料库 analyzers Setting, measurement, display The front panel ot the FAM is divided into thr tunctional sedions for easy operation and clear presentation ot the results, several parameters being displayed simultaneously: Lefthand section Carrier-frequency display and entry (with manual tuning) Middle section Result display and setting ot operating modes Righthand section Modulatlng-slgnal display measuring section tor modulating frequency. distortion, SINAD F 8ICtion: ci8PIaY 01 mcxjIMMon - - 8Id Frequency setting Setting is performed fully automat!- cally under microprocessor control; see description on next page. When a signal is applied, the FAM tunes automatically 10 the input frequency within 3 sand displays this frequency in the lefthand section with aresolution of 10Hz. If automatic tuning is not desired in specific cases. the frequency can be set via the keyboard (this ia important tor instance when measuring selective ca/l equipment. with data transmission and other techniques where no continuoos signal is available). For sud1 specific measurements. the other automatic tunc- tlons can also be suppressed. AF attenuator or AF range can be held at or brought to a particular setting. Modulation measurement, display The middle section is used tor setting the type ot modulation and time constant, seleding the filter and displaying the modul8tlon measure- ment result. An additional, analog display in the form 01 a light spot moving around a clrcle greatly 1acilitates adjust- ments by providing trend indication. The user simply selects the type 01 modulation - AM, FM or <pM - and, with FM, one 01 three deemphasis time constants. The Modulation Analyzer demodulates signals 01 any mode 01 modulation including simultaneous FM and AM. Welgthlng Three HP and three lP filters provide a great variety of weighting bandwidths and suppress unwanted signals. CCITT and CCIR standard filters (perceived Ioud- ness) can be inserted or retrofitted as options tor standard SI N measurements. Display 01 resulta (absolute or relative) The measured modulation can be displayed as an absolute vaJue or relative to a key-entered reference vaJue. This is very convenient if modulation is to be determined as a funclion of modulation frequency or carrier frequency. K8Yb08rdR clsPay fOf reI8IIve meu The high resolution (O.25%) end the high accuracy of the modulation depth indication (1.5%) permit precise measure- ments without needing recalibration. Type of detectlon The rneasurement of the AF modul at- ing-signal amplitude can be performed either with peak- responding detectlon (most frequently employed tor measur. ing wanted modulation) or with rms-responding detection (for example tor measuring unwanted ulation). The CCIR weightlng filter option includes the prescribed quasi-peak responding detector. RadioFans.CN 收音机爱 好者资料库 FAM Modulation-frequency I distortion measurement The frequency of the modulatlng slgn81 is displayed in the righthand section of the front panel. The O.1-Hz resolution is required tor measuring frequencies of calling signals or code signals tor squelch switching. F 8ICIIon: righIhn dIIP8Y n keyboan! 8ICIIon Ior uency n Evaluation of external AF signals The AF section, com- prising the weighting filter, frequency counter, detector and distortion meter. can be used tor the evaluation ot an extemal AF signal via a separate input socket. The Modulation Analy- zer can thus be used as an automatic AF voltmeter and as a psophometer. IEC-bus interface The Modulation AnaJyzer has an IEC- bus interface so it can be controJled by an external computer, eg by an R crystal aging 5x10-8/month). Specifications Freq,. . Wilh option FAM-82 , .36 GHz F requency seIIIng . . . . . . . . Display , R-*IIon. f < 1(Xk) Wfz . f f (Xk) Wfz . 56 kHz k) 120 MHz 56 kHz 10 1360 MHz aIIOm8tic I) 8c1gits 10Hzor1Hz 100 Hz 10 Hz :I: 1 cIgiI + errrx treq. lI88d SM$-81 <:1:1 x 10-I,noIII <:t5x 10-I,m<WIII <:t.1x10-I,oC 3V (-21k1+22.5dBrnl 10SOk 1360Mtiz .,Vm3V (-17k1 +22.5d8m1 RF allenualor !WQgr8mmaOie via ) Frequency _ment .nd auIomatic tuning for AM sml.; for. 550 MHz 10 60%. RadioFans.CN 收音机爱 好者资料库 analyzers AmplMud8 modulatIon - 1atkInrw;yrange 10HZtoalOkHz 10Hz to 20 kHz f 80% 10Hz- kHz(PHkreskjU8lAM) .-J- NQN f_30HztokHz S.1:2% S:t5% ofrdg ,ic)n:.l4Ito1kHz 8OUl100kHz :S:t4% S:t10% e- atf100Hz .1:01W atS/N-ft-AW) with SS50MH 560 MHz g,OA .,. - ccm(weighted z f80ce fittars mIS-teep. d8fecmr) SO.OI% SO.% Dl8IortIon wIhFAM-68 T88f(mlatot30) :KI/40m100Hz :KIHzIo20kHz sO.05% 05% aIO/300to1000Hz CClR weI!IIting . . . . . . . . . . . . . . . SO.05% .1 % 2/3 to 10 kHz AM wIth FM3j 12.5/15/17.5/20 kHz (,- 1 kHz, 50 kHz d8vi8tIon. Automalic tur1ng (5/N 30) . . . . tInng range :t3%; est:KIHzto3kHZ) 0.1% aummaacswtEhoflMlenteqU8ll;y AF cisIortion (at AF ou; Is outside of me88lJraIMe lange f_30 Hzto20 kHz) SI20MHz Display 4.THOin%orSlNADindB 40%. SO.2% Displayrange 0.lto50%.8U1ce(SlNAD) EmJr(THDS10%) S:tIO%otrdgorS:t1:t1d1git T est programmabIe AF FreqU8lCy range 10 Hz to aIO kHz range 0.1mVm3V(max.5Vpe8k) Display . 4 Unita :mV;relative:%.dB ReIC*Iton O.lmV EmJrwlhLP3/20kHz S.1:1.5%.1:0.1mV wittQltLP S :t1.5% .1:0.4mV(JO Hzto60kHz) S.1:3% .1:0.4 mV (80 m 100 kHz) WeighIXIg AFfacilli88In1tl8FAM (. W8igI1IW1g networks. Irequerw;y CXIUI1t.-. mef8r) can a8o be In YOII8ge remenII (LP aIO kHz) In z.,400kQll300pF.tk)atIng;BNC tem8e 4Oto80%mod ,so.4% AM mo 100kHz wtIh P88k-88P. ( P88k r8sIcaI8I FM) _HzIO80kHz S.t:1.5% 1$:3% m100kHz s.t:3% s.t:8% wtd11nW-f8SP. (1*18 reIkIu8I FM) _30HzmkHz S.t:3% Is% 8O1o100kHz s.t:8% s% A.-I8IFM_f S120 120m 55Om 1050m Wtz 55OWtz 1GaWtz ,.- Wilh CCITT erd nn8-f81P. S1HzS3Hz stHz S12Hz We91tWIg bIfIdwMjIh 30 Hz 10 20 kHz. wiIh . detedOr SSHzS141o1z saHz SW Wlth CCIR wei.;I*9 -.I d881nand SI8r8O 8tH r8Iio (CClR) ref.lo40 zdeNlon S8Io1z- (,S120z.V.mV) 72dBtyp. IncenIaI FM wittI AM (1_1 kHz,m-5O%:test Hz 3 kHz) . . . . . . $20 Hz (plus P88k FM) AF cIImItIon (at AF; - 30 Hz 10 20 kHz) 75kHzd8Yi8fion $0.1% 500 kHz d8IIi8IkJn . . . . . . . . . . . . SO.5% at ,- 30 Hz fo 15 kHz . . . . . . . . . (Iyp. 50) d8 down at st8f8o out- put _1 kHz 50d8down Deern . . . . . . . . . . . . . . . . . . . 50/75/750 IS. switdI-8eI8cIed FM nmIMb ,. vijo-., oIbI8 (13 r8ng88) Pt1888 modulation nl888Urement (with i .25 MHz) MomMtion freq*lCy r8Ig8 . . . . . . . Hz m 20 kHz Maximum m8UInI* d8Yiati0n . 500 rad (uplo 1 zmod.freq.) 0I8IX8Y . . . . . . . . . . . . . . . . . . . . . . 4 cIgit8 + 8I8tog i*8IkIn Units . . . . . . . . . . . . . . . . . . . 1bIOIute: rad; r818tiv8: %. d8 Resolution . . . . . . . . . . . . . . . . . 0.25%. mBX.: 0.001 rad Errorwith peakf8P. d8I8cb . s:t3.5% + peek l88k*I8I fM wiIh rm8-reep. d8IecU)r . . . . . . . S+5% +re81u81 !)M tpMaf SI20 120m 55010 105010 MHz SSOMHz 1050 MHz 1380 MHz Weiljlt8dwithCCm rId SO.OO2 SO.OO3 SO.OO8 0.012 30 Hz 20 kHz: rId 0.005 SO.01 sO.02 0.04 AF (at AF OU1put), d8Yi8ti0n4rad SO.1% PM nmMtiorI range progr8InIn8bIe (13 rWIg88) AFd8I8Ctof posiIive IX negatIw AF or 1heir ariIIwnetic - true ImS . iIdC8*n . or for -ve p8; Qe8t factor 1 0 Pe8k.d88Cb Rms- d8I8cb . . . . . . . . . WeIghtkIg1t8r8 Highpass (I-dB aJtoII frequency) . 10Hz (2 Hz 813 ce by chenging CXInn8CIion) . 30 Hz 81d 300 Hz (12 cel) WIIII leveI 8 da 8Iove mlMnum; 250 mV fa I., 120 MHz sO.% SO.6% VoItag8 range pIogr8nWt18bI8 (11 r8nge1) Outputa AM signal OU1put IV - . . . . . . . . . . . 1n8X. 1 V m 2 kO Bt 1 00% FM stereo signal CXItput IV - 1.5 V at 40 kt-Iz .,. CX)rrwp. to + 8 i1tt) 800 Q (Ior CIOSItaII -FM) AFOU1put(V ) 350mVIo1V,-oVon rIKxIIUIIon or AF 1E inwiI1 IEC825-1 (IEEE_); 24-QIfII8Ct necD lisIenerandtalk8r AH1, T4.12. RL1, DC1 - - M88tI- (frvquency, RF andAF aG. P+or p-; at f. 120 MHz: t + 100 InS) wWI -*IkIn 10Hz/100Hz 1Hz For trlggered RF arid modulalkln meuUIement FM, !IM S2SO lnI S2050 InS AM 1nS Automallc RF. nmA8tioII and AF 1nMMI when changing fIequency or alter apPying the RF leY8I typ. 3.5 a alter watming up . . . . . . . . . . . . typ. 1.5 a DlST/SI typ.8a aIter-*19UP typ.28 rl1lXlt freq. 10 MHz) G8n8r81d8f8 0peraIWIg 8mper8n range . . . . . . +5 +45C Slorager8nge -4010 +70C RFI su . . . . . . . . . . . . . . voe r8do PIOI8cIon m81k: D9P 527 GI Mechanic8I ;e8I(a,-R)6 . 8110*- 8Id vibrIIion-I8I8d 10 DIN 40048, P8/1I7 and8 (. 10 IEC . 68-2-27 8Id 68-2-6) POWeI 115/125/2Z/235V:t10% 47 440 Hz (80 VA), saf8ty cIass I D, weIg 347 mm x 2O61m1 X 370 1m1, 13.5 kg Ordering information Order d88igNtion . . . . . . . . . FAM 55 kHzto 120 MHz Accessorie8 supplied . . . . . OptIons . An8IyZ8r F AM .2015.54 cabIe, ad8pI8r (for PC bO8rds) SMS-81 .302.8818.02 - 0 8 d I a t Q 1.36-QHz F Ex18nSKIn . ., C C I T T F i I l e r CCIRFIIIer D I S T / S I N A O M e I e r 19Ad8p4.-. . FAM-B2 . 334.4918.02 FAM-B8 . 334.5614.02 FAM-B7 .334.5514.02 FAM-S8 . 334.5114.02 FAM-Z9 . 349.7318.02