(fout) meten AZ1 met AVO-160- Resultaat met MK4 (Algemeen)

door VCM163 , 31.08.2014, 15:32 (3740 dagen geleden) @ electronenbuizen

In the document that I wrote "AVO VCM - Circuit Comparisons" in chapter 3.3 you can see that for the two ranges 30mA and 60mA for Diode/Rectifier measurements in the VCM163 AVO did not use the same center measurement for some reason. In the VCM163 the center of the green scale is set at 68.9mA and 36.1mA for those two ranges whereas they are set at 60.1mA and 30.1mA for the other VCMs. This is due to the fact that AVO uses two resistors for these ranges that produce this deflection on the meter (1.3 MOhm and 680 KOhm). If you however changes these resistors to 1.134 MOhm and 566.33 KOhm you will get exactly the same center spot as on the other AVO VCMs. I have never found any design document from AVO that shows why this was chosen like this, it could be one of the famous "errors" found throughout the AVO documentation (there are a few similar component errors like this and also a few in the circuit diagrams and text throughout most of AVO document, was this to hide the true design from competitors or just plain errors?).

If someone is willing to host the document I wrote it will be ok with me as long as it is unchanged and in its original form. Please contact me to get a copy, it turns out that most email providers can't handle the large document so I will share a link from my DropBox account where you can download it for a short time.

/Martin