Nice work getting it together. The fact that you need such a silly low value pull-up suggests that you've got something pretty bonkers going on at that pin. Perhaps it's a shorted input buffer transistor that's just gone more or less short across all pins; in such a case, you would expect it to have a low impedance to both ground and the actual input of the circuit, and you'd need to overcome its resistance to ground in order to raise the signal level going forward into the rest of the IC - ergo requiring a strong pull-up. It would be fun to see if the short could be "blown away" by applying a relatively large energy burst to the input, but that would also drive the circuit on the other side of the transistor way out of its boundaries, and would probably make the input fail completely - so I don't recommend doing it!
Obrigado pelo vídeo, meu ut61 estava com FC com1,5v a escala de tensão DC não estava lendo e a escala ohms não funcionava, coloquei resistor de 22ohm igual do vídeo e fico ótima as escalas.
I've used a 5k resistor... and it seems to work fine. For some reason.. smaller resistors heated when on Ohm measurements. My D4 was ok.. but not the pullup, so i suspect that your reset is related to the diodes used as mine doesn't do any reset.
Habe mir mal bei ebay ein altes Voltcraft Mutimeter der Mittelklasse gekauft, kennst du vielleicht eine open source Software für den RS232 Port des Multimeters ? Die beigelegte Diskette ist nicht mehr lesbar.
Hi sir useful video i had the same issue with this particular multimeter.i replace the diode package with two smd diode and function selection issue solved and all functions working correctly except voltage measurement that shows an offset voltage even when probes shorted together.( It's showing -0.8v)and diode mode has the same problem it's showing 1.4v. originally the isuee is caused by over voltage i inspected the board an there was no visual blown components.can u help me with that??
it should not need such a low value resistor to keep that pin to 0v, i would disconnect one side of the resistor, then remove the switch so all contacts are open, then measure resistance from 0v common to each of the Function lines. They all use the same logic so they will have identical internal pull up resistors, except for the faulty one. Its unfortunate that you may find its the processor that has damage :-(
+zx8401ztv Yes, the processor is probably damaged. That's why that low value resistor is there. With it, the meter works fine. Your comment does not suggest a better way to repair this, so that resistor will stay where it is.
+DrCassette Sorry, but you didnt sound like you fully understood its design, if you did then you would not be asking for comments on the subject. I was just trying to help, the fix is: purchase the chip and get someone with a smd solder kit to replace it.
Assuming that somebody doesn't understand what he is talking about just because he is asking for feedback is quite rude. And why should I go through the trouble of getting the (expensive) chip and replacing it if I can still get the original one to work?
+DrCassette I did say "didnt sound like you fully understood its design", im not calling you an idiot, im just saying you dont know everything about it. You slapped me for trying to help you with testing the inputs, then almost told me to go away because i didnt give you a fix. Sorry, i wont bother you again :-(
Sehr schön gemacht, auch wenn ich nur ca. 70 % vom sprachlichen verstanden habe, so ist das Thema und Sinn des Videos aber rübergekommen. Schade, dass du die meisten Videos oder im Prinzip fast alle auf Englisch erklärst. Ist eine Interessante Sache die Elektronik, da findet man leider nur wenig Deutsche Informationsvideos darüber. Daher ist es etwas Schwierig, da man nun hier die Sache an sich die im Video vorgetragen wird versucht zu verfolgen und zu verinnerlichen plus noch die Sprache verstehen und richtig zu deuten, bzw. übersetzten. Vielleicht kannst du ja mal ein paar deutschsprachige trotzdem mit einbauen in deinen Kanal ;)
+Zerno Für deutsche Technik-Videos habe ich den Kanal "vfocos". Da ist momentan aus zeitlichen/organisatorischen Gründen zwar nicht so viel los, aber was nicht ist, kann ja noch werden.
![Testing Multimeters | UT61E repair [3/4]](http://i.ytimg.com/vi/M_p1SKtAbuc/mqdefault.jpg)
![Testing Multimeters | UT61E repair [3/4]](/img/tr.png)
Nice work getting it together. The fact that you need such a silly low value pull-up suggests that you've got something pretty bonkers going on at that pin. Perhaps it's a shorted input buffer transistor that's just gone more or less short across all pins; in such a case, you would expect it to have a low impedance to both ground and the actual input of the circuit, and you'd need to overcome its resistance to ground in order to raise the signal level going forward into the rest of the IC - ergo requiring a strong pull-up. It would be fun to see if the short could be "blown away" by applying a relatively large energy burst to the input, but that would also drive the circuit on the other side of the transistor way out of its boundaries, and would probably make the input fail completely - so I don't recommend doing it!
Well done for fixing it
Obrigado pelo vídeo, meu ut61 estava com FC com1,5v a escala de tensão DC não estava lendo e a escala ohms não funcionava, coloquei resistor de 22ohm igual do vídeo e fico ótima as escalas.
Amazing! I was not expecting the value of the resistor to be that low, but whatever works, I guess. Believe me, that fix doesn't look ugly at all :P
Why not replacing with the same diode which was faulty instead of doing this all messy arrangements ?
Because the suitable diode would have had to be ordered online, the diodes I installed I already had in stock.
Hi can you please tell me where you obtained the schematics for the multimeter?
Great work.
I've used a 5k resistor... and it seems to work fine. For some reason.. smaller resistors heated when on Ohm measurements. My D4 was ok.. but not the pullup, so i suspect that your reset is related to the diodes used as mine doesn't do any reset.
Hi! I have the same device, can you tell me why it can show -0.4v on the display in DC voltage measurement mode, other functions work correctly
Does it still show -0.4V when the positive and negative probes are shorted together? In this case you would have a problem with the calibration
@@DrCassette When the plus and minus probes are shorted and when they are not!
@@serglyashenko6872 Seems like there is a calibration problem then...
@@DrCassette It's a pity, but the voltage adjustment doesn't help vr1, there is nothing visually burnt...
@@DrCassette Where can I read about the calibration of this device, I can't find the reason for the -0.4v indicator(((
1ss268(in scheme D4) can be replaced by bat54c.
Danke für die Videos haben mir sehr geholfen 👍
Habe mir mal bei ebay ein altes Voltcraft Mutimeter der Mittelklasse gekauft, kennst du vielleicht eine open source Software für den RS232 Port des Multimeters ? Die beigelegte Diskette ist nicht mehr lesbar.
+Dorf Schmidt
Nein, davon habe ich leider keine Ahnung...
Do u mind to share the schematic by any medium? Email maybe. Need to mod the DMM a bit but didn't seem to find the schematic anywhere.
The schematic was send to me by somebody and I don't know if they are OK with me passing it on. Sorry, I can't help you.
Good job!
Hi sir useful video i had the same issue with this particular multimeter.i replace the diode package with two smd diode and function selection issue solved and all functions working correctly except voltage measurement that shows an offset voltage even when probes shorted together.( It's showing -0.8v)and diode mode has the same problem it's showing 1.4v. originally the isuee is caused by over voltage i inspected the board an there was no visual blown components.can u help me with that??
it should not need such a low value resistor to keep that pin to 0v, i would disconnect one side of the resistor, then remove the switch so all contacts are open, then measure resistance from 0v common to each of the Function lines.
They all use the same logic so they will have identical internal pull up resistors, except for the faulty one.
Its unfortunate that you may find its the processor that has damage :-(
+zx8401ztv
Yes, the processor is probably damaged. That's why that low value resistor is there. With it, the meter works fine. Your comment does not suggest a better way to repair this, so that resistor will stay where it is.
+DrCassette Sorry, but you didnt sound like you fully understood its design, if you did then you would not be asking for comments on the subject.
I was just trying to help, the fix is: purchase the chip and get someone with a smd solder kit to replace it.
Assuming that somebody doesn't understand what he is talking about just because he is asking for feedback is quite rude.
And why should I go through the trouble of getting the (expensive) chip and replacing it if I can still get the original one to work?
+DrCassette I did say "didnt sound like you fully understood its design", im not calling you an idiot, im just saying you dont know everything about it.
You slapped me for trying to help you with testing the inputs, then almost told me to go away because i didnt give you a fix.
Sorry, i wont bother you again :-(
It seems like we keep misunderstanding each other. I'm sorry.
Excelente!
Sehr schön gemacht, auch wenn ich nur ca. 70 % vom sprachlichen verstanden habe, so ist das Thema und Sinn des Videos aber rübergekommen. Schade, dass du die meisten Videos oder im Prinzip fast alle auf Englisch erklärst. Ist eine Interessante Sache die Elektronik, da findet man leider nur wenig Deutsche Informationsvideos darüber. Daher ist es etwas Schwierig, da man nun hier die Sache an sich die im Video vorgetragen wird versucht zu verfolgen und zu verinnerlichen plus noch die Sprache verstehen und richtig zu deuten, bzw. übersetzten. Vielleicht kannst du ja mal ein paar deutschsprachige trotzdem mit einbauen in deinen Kanal ;)
+Zerno
Für deutsche Technik-Videos habe ich den Kanal "vfocos". Da ist momentan aus zeitlichen/organisatorischen Gründen zwar nicht so viel los, aber was nicht ist, kann ja noch werden.
Ah ok, ja danke. Stimmt, was nicht ist kann noch werden. Bitte weiterhin so interessante Videos! Grüße