力士樂Rexroth放大器VT-HMC-1-1X/M-0-00/00
R901361289 VT-HMC-1-1X/M-0-00/00
R988118233 VT-HMC-1-1X/M-0-00/DPQ
R901361305 VT-HMC-1-1X/M-P-00/00
R901441904 VT-HMC-2-1X/M-0-00/00
R901361303 VT-HMC-2-1X/M-P-00/00
R900927936 VT-HNC100-1-1X/260
R900962356 VT-HNC100-1-2X/M-08-0-0
R900780959 VT-HNC100-1-2X/M-08-0-C/INK2
R900780960 VT-HNC100-1-2X/M-08-C-0/INK2
R900966849 VT-HNC100-1-2X/M-08-I-0
R900965731 VT-HNC100-1-2X/M-08-P-0
R901005336 VT-HNC100-1-2X/M-08-P-0/INK2
R900963524 VT-HNC100-1-2X/M-24-0-0
R900704326 VT-HNC100-1-2X/M-24-0-C
R900759182 VT-HNC100-1-2X/M-24-0-C/INK2
R900969414 VT-HNC100-1-2X/M-24-P-0
R900331704 VT-HNC100-1-2X/SIMULATOR
R900955334 VT-HNC100-1-2X/W-08-0-0
R900955334U VT-HNC100-1-2X/W-08-0-0 REMANUFACTURED
R900770488 VT-HNC100-1-2X/W-08-0-0/FIL
R900973251 VT-HNC100-1-2X/W-08-0-0/INK2
R900618718 VT-HNC100-1-2X/W-08-0-B
R900750908 VT-HNC100-1-2X/W-08-0-D
R900777308 VT-HNC100-1-2X/W-08-0-E
R900959000 VT-HNC100-1-2X/W-08-C-0
R900959000U VT-HNC100-1-2X/W-08-C-0 REMANUFACTURED
R900739511 VT-HNC100-1-2X/W-08-C-0/INK2
R900955332 VT-HNC100-1-2X/W-08-I-0
R900955332U VT-HNC100-1-2X/W-08-I-0 REMANUFACTURED
R900710764 VT-HNC100-1-2X/W-08-I-0/INK2
R900760931 VT-HNC100-1-2X/W-08-L-0
R900958999 VT-HNC100-1-2X/W-08-P-0
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R901011208 VT-HNC100-1-2X/W-08-P-0/ENDA
R900734009 VT-HNC100-1-2X/W-08-P-0/INK2
R900968059 VT-HNC100-1-2X/W-08-P-0/TOOLEX01
R900968060 VT-HNC100-1-2X/W-08-P-0/TOOLEX02
R900968061 VT-HNC100-1-2X/W-08-P-0/TOOLEX03
R900959628 VT-HNC100-1-2X/W-08-P-B
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R900758135 VT-HNC100-1-2X/W-08-S-0
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R900958998 VT-HNC100-1-2X/W-24-0-0
頻譜分析儀是一種帶有顯示裝置的超外差式接受設(shè)備,是研究電信號頻譜結(jié)構(gòu)的儀器,,用于信號失真度,、調(diào)制度、譜純度,、頻率穩(wěn)定度和交調(diào)失真等信號參數(shù)的測量,,可用以測量放大器和濾波器等電路系統(tǒng)的某些參數(shù),是一種多用途的電子測量設(shè)備,。前置放大器通常是指放置在信源與放大器級之間電路或電子設(shè)備,,是專為接受來自信源的微弱電壓信號而設(shè)計的。而信號發(fā)生器,,一般會被稱之為信號源,,也會被叫做是振蕩器,這是一種可以支持多種頻率波形以及電平信號的設(shè)施,。
頻譜分析儀中的前置放大器的作用是什么,?
前置放大器:放在所有處理電路之前(就在輸入口的后面)的功率放大器,增大信號強度,,增大信噪比減小底噪的干擾,。實際是信號增大,底噪不變,。但是以信號為參考,,認為信號不變,也可以說成底噪降低,。
如何使用頻譜分析儀,、前置放大器和信號發(fā)生器來測量噪聲系數(shù)?
只用頻譜分析儀和前置放大器,,就能作許多噪聲系數(shù)測量,。只需用頻譜分析儀、前置放大器和信號發(fā)生器,,就能覆蓋被測器件的頻率,。這種方法的精度低于需要經(jīng)校準噪聲源的Y 因素技術(shù),與所關(guān)注頻率的分析儀幅度精度相當,。具體測量步驟為:
1. 把信號發(fā)生器和頻譜分析儀設(shè)置為所測噪聲系數(shù)的頻率,,測量器件的增益。把該值標為Gain(D),。
2. 同樣方法測量前置放大器增益,。把該值標為Gain(P)。
3. 斷開頻譜分析儀的任何輸入,,把輸入衰減器設(shè)置為0dB,。前置放大器輸入沒有任何連接,。把它的輸出接到頻譜分析儀輸入。在作這一連接時,,您會看到分析儀顯示的平均噪聲級的增加,。
4. 把被測器件的輸入接至其特性阻抗,把輸出接到前置放大器輸入,。此時分析儀顯示的噪聲級應(yīng)增加,。
5. 把頻譜分析儀視頻帶寬(VBW)設(shè)置為分辨率帶寬的1%或更低。按標記功能(MKR FCTN)鍵,,然后按Noise Marker On 軟鍵,。把標記放置在所要測噪聲系數(shù)的頻率上。讀以dBm/Hz 為單位的標記噪聲功率密度讀數(shù),,把它標為Noise(O)。
6. 然后計算被測器件的噪聲系數(shù)NFig:NFig = Noise(O) - Gain(D) - Gain(P) + 174 dBm/Hz,。![638476529741235602220.jpg](https://img50.chem17.com/b668da8d58269a5221520449e33d0719b70f36e692472933cb27dc007f9aa3423644c7f5e2448933.jpg)