示波器與萬用表

前世今生：https://blog.csdn.net/weixin_30075701/article/details/112188635 

1. DSO

1.1 Rigol 國產第一品牌

http://www.batronix.com/shop/rigol/DS1000Z.html 
50M改100M：http://www.instructables.com/id/Hacking-the-Rigol-DS1052E-Oscilloscope-with-Linux/ 
改進錯誤的PLL： http://www.eevblog.com/forum/projects/project-yaigol-fixing-rigol-scope-design-problems/ 

普源Rigol Mso5074是示波器(2-4CH 70-350M均配350M探頭)、邏輯分析儀LGA(16CH upto 1G需PLA2216探頭或DIY)、頻譜分析儀(FFT)、任意波形發生器AWG(2CH25M需購AWG軟件)、數字電壓表(3-digit看來是8bit平均而來)、頻率計和累加器(6-digit)、協議分析儀(RS232/UART, I2C, SPI, CAN, LIN, I2S, FlexRay, and MIL-STD-1553)的組合。除LGA/AWG外都是軟件功能，意思不大。這個品牌俗稱日狗，bug多，標稱8G/s是單通道的，數據要直接由RAM導出才有，編程手段多是優點。軟件升級據稱能解除選件限製，破解可到350M，限V00.01.03.00.01(2020-04-27發布)的固件：https://blog.csdn.net/qq_15242011/article/details/109093569 

1.2.Hantek 買斷南韓

1.2.1 dso5000

固件：http://www.hantek.com/en/PagesFW_Vzxgj.html 
60M改200M：https://www.circuitsathome.com/measurements/hantek-dso5000-series-oscilloscope-modifications-part-1-doubling-the-bandwidth-of-dso5102b  https://www.circuitsathome.com/measurements/hantek-dso5000-series-oscilloscope-modifications-part-2-reducing-fan-noise 

2.2 2090 USB scope

https://fabiobaltieri.com/2013/07/10/inside-a-hantek-dso-2090-usb-oscilloscope/ 
https://docs.google.com/document/d/1T5P11AM2YI6EQkrYAchQWeC9Fstncj83eMYDBsULW1U/edit 
https://forum.pjrc.com/archive/index.php/t-25730.html 

DSO4102S: 帶25M DSS:

1.3 鼎陽Siglent

SDS2074X Plus破解到500MHz: https://www.mydigit.cn/forum.php?mod=viewthread&tid=176738&extra=page%3D1   https://www.eevblog.com/forum/testgear/siglent-sds2074x-upgrade-to-300-mhz-and-serial-decode-beyond-screen-display/

1.4. Tek

Tektronix CRT for TEK.2400 SERIES 154-0850-01

1000X to 200M: https://www.youtube.com/watch?v=eeds2QsUa_w? 

1.5. Probe

http://www.davmar.org/TE/TekConcepts/TekProbeCircuits.pdf 

Tek Probes compatible with 1103 power supply: outputs +/-5V,+/-12V +-2%, 300mA each. http://www.trs-rentelco.com/Manual/TEK_1103_Manual.pdf

P6243/6245 FET 10:1 probe, 1M1pF,+-8Vin,1/1.5GBW, uses +-5V. 這類有源探頭接口是TekProbe-BNC Level2, N2744用於BNC或HP/Agilent/Keysight的示波器上轉接Tek有源探頭。1點鍾順時針：-15V/-5V/Offset（+-1V)/Data/GND/+15V/+5V/Clk/Data。
http://www.testequity.com/documents/pdf/tekvpi.pdf 
http://www.eevblog.com/forum/projects/tektronix-tekprobe-power-supply-for-agilent-rigol-and-other-oscilloscopes/ 
ADA400 Differential Amp http://www.es-france.com/pdf/ADA400A.pdf

Uses +5V and +/-15V supply rails. Does not use the Offset feature.
P6243 FET Probe http://exodus.poly.edu/~kurt/manuals/manuals/Tektronix/TEK P6243 Service.pdf Uses the +/-5V supply rails. Does not use the Offset feature.
P6245 FET Probe http://exodus.poly.edu/~kurt/manuals/manuals/Tektronix/TEK P6245 Instruction.pdf Uses the +/-5V supply rails. This DOES use the offset feature to extend the probe DC input range, however, I've never used it since all my measurements are within the standard +/-8V input range (Offset = 0V).
The 1103 Offset output has a range of +/-1V which extends the input range of the P6245 from -10V +/- 8V up to +10V +/- 8V (well, sort of, it's clipped at +/-15V but you get the idea).

P52xx high voltage differntial probe, ~5M4pF, x50x500

x1x10 active probe: http://www.eevblog.com/forum/projects/high-z-wideband-buffer-amp-for-50-ohm-cro-inputs/25/ 

x10x100: http://www.eevblog.com/forum/projects/cheap-differential-probe-ad8130/ 

Differential probe DIY：

http://www.linear.com/solutions/6058  http://newae.com/sidechannel/cwdocs/naecw501_hwdiffprobe.html  http://www.eevblog.com/forum/projects/my-first-project-low-cost-differential-probe/

http://www.eevblog.com/forum/projects/high-voltage-differential-probe-design-for-review/25/  https://www.google.com/search?q=differential+probe+circuit
3V3>+-5V: LM2685,TPS65130,ADP5070+LDO,Max682+889S
Diff Probe2：   AD8130@G5-300M seems best, LT6268-10(G10-200M FET),LT6409 ADCdrv(10GBW),
Twinaxi-BNC: MC23564/23577, http://www.digipart.com/part/MC23564  不過USB3更好，腳多可與Tek兼容。

最簡單的差分探頭，用雙絞同軸線，一端接示波器兩個通道，另一端兩芯線作為探頭，兩屏蔽層互聯但懸空，兩通道需校準幅度和相位。單端探頭可用雙層屏蔽電纜如RG223/142，內存用於信號地，外層接地屏蔽掉感應噪音。探頭接地線是感性要盡量短。

低電平的信號測量，建議用示波器50歐輸入(沒有的話加適配器)接RG-174(RG-316更好)同軸電纜，電纜另一端就近接地，芯線接953歐電阻後即為20:1探頭,僅0.5PF；Tek P6230~1 1.5G探頭類似，但用450歐電阻。相比之下P6139A 500M探頭輸入電容為8pF。

x1x10 active probe: http://www.eevblog.com/forum/projects/high-z-wideband-buffer-amp-for-50-ohm-cro-inputs/25/ 
x10x100: http://www.eevblog.com/forum/projects/cheap-differential-probe-ad8130/ 
差分探頭：http://bardagjy.com/?p=1664 
1.5 A/D: 有LVDS串口輸出的可接FPGA用其內部RAM。AD9600 2ch 10bit 105-150M, 1-2Vpp in, 並口出。
http://www.analog.com/en/products/analog-to-digital-converters/high-speed-ad-10msps.html 
1.6 開源軟件
STM32F407，A/D 3ch 12bit 2.4M最大6M單通道：http://bbs.armfly.com/read.php?tid=3886&page=1

3.萬用表

3.1 Fluke 87V 4-1/2

3.2 HT206D鉗表表備忘

http://www.habo-test.com/sale-11356939-ht206d-ac-dc-digital-clamp-meter-current-voltage-resistance-continuity-ncv.html

https://www.fluke.com/en-us/product/electrical-testing/digital-multimeters/fluke-87v

按LED鍵屏幕可亮20秒，長按可點亮LED燈；屏幕更新速率約3Hz。在3A或80V以上或30歐以下時屏幕會改紅色；

最下的檔位Lo-Z，將電壓表的輸入阻抗由10M降為300K以減小分布電容的影響，可測量300KHz的電壓源；

Min/Max鍵與Fluke不同，不能同時存儲Min/Max/AVG，隻是顯示當前Max或者Min的值，但實測可以顯示汽車啟動電流最大值；長按退出；

右手拇指側的NCV(Non contact voltage)鍵長按可啟閉NCV，啟用時鉗口頂端凸起為無線探頭做電筆用，可顯示H/L；

左側Z/F多功能鍵可用於改變測量檔類如切換C/F、選LF低通、DC電流檔清零、變為600mV滿度等；

鉗表測電流的精度較低為2.5%，且交直流均隻有60/600A兩檔，使用時應將單線至於鉗口中心。如果把火/零線都鉗住，磁場將抵消讀數將為零；

該表不足之處是沒有萬用表的表筆式電流測量。但可利用600mV檔並接0.1Ohm精密電阻，用作6A接入式電流測量，即1mV對應於10mA，此時burden voltage為0.1V/A而Fluke 87V為0.03V/A。若降低電阻為0.03Ohm則滿刻度為20A。有源方案：http://alternatezone.com/electronics/ucurrent/uCurrentArticle.pdf

似乎可在兩表筆間加四線插座：+3V/GND/TX/RX，機外升壓成+-2.5V，加MC12080x2可做1G/100頻率計，按上麵鏈接可加6A/60mA/600uA電流檔，加Arduino可做控製器。

4. 兆歐表megameter

最早是搖表，手搖發電200V以測絕緣。找到下圖後發現國產有低價的兆歐表