示波器与万用表

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

1. DSO

1.1 Rigol 国产第一品牌

http://www.batronix.com/shop/rigol/DS1000Z.html 
50M改100M：http://www.instructables.com/id/Hacking-the-Rigol-DS1052E-Oscilloscope-with-Linux/ 
改进错误的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探头)、逻辑分析仪LGA(16CH upto 1G需PLA2216探头或DIY)、频谱分析仪(FFT)、任意波形发生器AWG(2CH25M需购AWG软件)、数字电压表(3-digit看来是8bit平均而来)、频率计和累加器(6-digit)、协议分析仪(RS232/UART, I2C, SPI, CAN, LIN, I2S, FlexRay, and MIL-STD-1553)的组合。除LGA/AWG外都是软件功能，意思不大。这个品牌俗称日狗，bug多，标称8G/s是单通道的，数据要直接由RAM导出才有，编程手段多是优点。软件升级据称能解除选件限制，破解可到350M，限V00.01.03.00.01(2020-04-27发布)的固件：https://blog.csdn.net/qq_15242011/article/details/109093569 

1.2.Hantek 买断南韩

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: 带25M DSS:

1.3 鼎阳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. 这类有源探头接口是TekProbe-BNC Level2, N2744用于BNC或HP/Agilent/Keysight的示波器上转接Tek有源探头。1点钟顺时针：-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  不过USB3更好，脚多可与Tek兼容。

最简单的差分探头，用双绞同轴线，一端接示波器两个通道，另一端两芯线作为探头，两屏蔽层互联但悬空，两通道需校准幅度和相位。单端探头可用双层屏蔽电缆如RG223/142，内存用于信号地，外层接地屏蔽掉感应噪音。探头接地线是感性要尽量短。

低电平的信号测量，建议用示波器50欧输入(没有的话加适配器)接RG-174(RG-316更好)同轴电缆，电缆另一端就近接地，芯线接953欧电阻后即为20:1探头,仅0.5PF；Tek P6230~1 1.5G探头类似，但用450欧电阻。相比之下P6139A 500M探头输入电容为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/ 
差分探头：http://bardagjy.com/?p=1664 
1.5 A/D: 有LVDS串口输出的可接FPGA用其内部RAM。AD9600 2ch 10bit 105-150M, 1-2Vpp in, 并口出。
http://www.analog.com/en/products/analog-to-digital-converters/high-speed-ad-10msps.html 
1.6 开源软件
STM32F407，A/D 3ch 12bit 2.4M最大6M单通道：http://bbs.armfly.com/read.php?tid=3886&page=1

3.万用表

3.1 Fluke 87V 4-1/2

3.2 HT206D钳表表备忘

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键屏幕可亮20秒，长按可点亮LED灯；屏幕更新速率约3Hz。在3A或80V以上或30欧以下时屏幕会改红色；

最下的档位Lo-Z，将电压表的输入阻抗由10M降为300K以减小分布电容的影响，可测量300KHz的电压源；

Min/Max键与Fluke不同，不能同时存储Min/Max/AVG，只是显示当前Max或者Min的值，但实测可以显示汽车启动电流最大值；长按退出；

右手拇指侧的NCV(Non contact voltage)键长按可启闭NCV，启用时钳口顶端凸起为无线探头做电笔用，可显示H/L；

左侧Z/F多功能键可用于改变测量档类如切换C/F、选LF低通、DC电流档清零、变为600mV满度等；

钳表测电流的精度较低为2.5%，且交直流均只有60/600A两档，使用时应将单线至于钳口中心。如果把火/零线都钳住，磁场将抵消读数将为零；

该表不足之处是没有万用表的表笔式电流测量。但可利用600mV档并接0.1Ohm精密电阻，用作6A接入式电流测量，即1mV对应于10mA，此时burden voltage为0.1V/A而Fluke 87V为0.03V/A。若降低电阻为0.03Ohm则满刻度为20A。有源方案：http://alternatezone.com/electronics/ucurrent/uCurrentArticle.pdf

似乎可在两表笔间加四线插座：+3V/GND/TX/RX，机外升压成+-2.5V，加MC12080x2可做1G/100频率计，按上面链接可加6A/60mA/600uA电流档，加Arduino可做控制器。

4. 兆欧表megameter

最早是摇表，手摇发电200V以测绝缘。找到下图后发现国产有低价的兆欧表