# Help with tracing a pedal.



## dmnCrawler (Aug 15, 2020)

I am trying to trace the KMA - Tyler The Freq Splitter.  I am having trouble figuring out how to determine the SMD capacitor values. There are no markings on the caps and if I am correct they can not be measured in place. I am unsure of the values of C1, C4, C5, C14, C15. I am guessing on the input diode value [1N4148]. And I am very unsure of the schematic. I have spent several days going over it and think I have all the traces correct, but I have only been building for 4 months and my knowledge is limited.

Also the low and high pass jacks do hook up to the wrong filters. I believe they are miss labeled on the PCB. I will fix them in the final version of the schematic. Any help, hints ,tips or other resources to use are greatly appreciated.

If this is the wrong place please let me know the right place. 











C1xR1220-1​22RTHD1xC247​16VR22204​2.2MD25mm LEDWhite ClearC3220​16VR31002​10kD33mm LEDYellow ClearC4xR42203​220kD43mm LEDYellow ClearC5xR52203​220kC610​16VR63902​39kTRIM105​C710​16VR71002​10kTRIM105​C847​16VR81001​1kTRIM105​C9xR91001​1kC1010​16VR102201​2.2kLow PassA100KDualC1110​16VR113300​330RLevelA100KC1210​16VR121002​10kMixB10KC1310​16VR131004​1MHigh PassA100KDualC14xR142203​220kC15xR151002​10k+ -SPDTON-ONC1610​16VR162204​2.2MC1710​16VR172204​2.2MWood3PDTC1810​16VR181002​10kBypass3PDTR191002​10kSteel3PDTIC17660SCPAZR20​1002​10kIC2TL074CR211003​100kINStereo SwitchingIC3TL072CR221001​1KOUTStereo SwitchingIC4TL074CR231001​1KLP SendStereo SwitchingR241001​1KLP ReturnStereo SwitchingEnclosure1590XXR251002​10kHP SendStereo SwitchingR261004​1MHP ReturnStereo SwitchingR271001​1KR281004​1M


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## Robert (Aug 15, 2020)

Unfortunately you really need to remove them to get an accurate measurement.

Be careful, if any of them are SMD _film_ capacitors they will melt when you try to desolder them.   Those have to be isolated in-circuit by removing _other_ components around them, then you can measure them while still installed on the PCB.


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## dmnCrawler (Aug 15, 2020)

Robert said:


> Unfortunately you really need to remove them to get an accurate measurement.
> 
> Be careful, if any of them are SMD _film_ capacitors they will melt when you try to desolder them.   Those have to be isolated in-circuit by removing _other_ components around them, then you can measure them while still installed on the PCB.



 I had a feeling it would not be easy. And I believe it is only the film caps that I need measurements for. I am hoping that someone may have some ideas of ranges just from the circuit design and where the caps are placed.


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## Devoureddeth (Aug 21, 2020)

Robert said:


> Unfortunately you really need to remove them to get an accurate measurement.
> 
> Be careful, if any of them are SMD _film_ capacitors they will melt when you try to desolder them.   Those have to be isolated in-circuit by removing _other_ components around them, then you can measure them while still installed on the PCB.



Have you ever tried the SMD multimeter tweezers? I have tried the cheaper versions and it is only useful for resistors.


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## Robert (Jul 3, 2022)

Devoureddeth said:


> Have you ever tried the SMD multimeter tweezers? I have tried the cheaper versions and it is only useful for resistors.



Wow, I missed this... Better late than never though, right?

I have since picked up another Pace station with MT-200 tweezers.    It has _significantly_ cut down the amount of time to takes to measure SMD components.   Unfortunately it vaporizes film caps just as quickly as a regular iron, but it makes it much easier to isolate them in the circuit.

It gets enough use that I bought a second station _just_ for the tweezers so I can go back and forth with the iron quickly.


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