Your mystery is like "Mitos of Ariadnes" (from Greek Mythology) same psu, identical adapter but the noise is differente, but remaining the answer of Flash2light what is marking of U2 in ver. 3.3. Probably, there is a difference there...Well that's not too bad, I'll be more scared to look around for the answer if it resembled the story of Medusa, it wouldn't be cool turning to stone.
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Carrington about BW, you know (I think) the works of rf-loop, he has show us that this oscilloscope has over 200MHz bandwidth.
If I remember well you have additional the Rigol 2000 Series, I think that is one category over than SDS7102 and it is not fair to compare the two of them. About Rigol DS1052 or DS1102 that is the competition.
But if I remember well, the noise of SDS at full BW (5mV) is under 1mV. At the beginning when the noise gnd is very high (160-200mV) I couldn't to examine a signal with a few mV, it was full with artifacts and not stable - only with my old analoge Hameg I could.
Today with my mods (I have a noise gnd 40-55mV peak to peak) there is no any difference between Hameg and Owon in signals with a few mV, very stable and clearly.
Your mystery is like "Mitos of Ariadnes" (from Greek Mythology) same psu, identical adapter but the noise is differente, but remaining the answer of Flash2light what is marking of U2 in ver. 3.3. Probably, there is a difference there...Well that's not too bad, I'll be more scared to look around for the answer if it resembled the story of Medusa, it wouldn't be cool turning to stone.
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Tomc: Is the difference between yours and these very marked?
Your mystery is like "Mitos of Ariadnes" (from Greek Mythology) same psu, identical adapter but the noise is differente, but remaining the answer of Flash2light what is marking of U2 in ver. 3.3. Probably, there is a difference there...Well that's not too bad, I'll be more scared to look around for the answer if it resembled the story of Medusa, it wouldn't be cool turning to stone.
There are a couple of things I've been thinking about. I took a real good look at my new PSU board and discovered that one of the new decoupling capacitors is probably missing. There is no capacitor where C23 is supposed to be. C23 is supposed to be at the end of the adapter board connector. I see glue residue, as if the component was there but fell off during the soldering process. However, I don't think this would cause such a big difference in noise by itself.
Flash2light, can you tell me if this capacitor is present on your PSU board?
The other thing I've been thinking about is that I don't have the battery option. With a battery installed you have additional filtering for the 8.4V supply. The battery itself can act as a super capacitor. I don't know for sure if the results from dgmoore78@yahoo.com and Flash2light were obtained with the optional battery installed.
dgmoore78@yahoo.com and Flash2light, can you clarify this, and if possible, if your test was done with the battery installed, can you do the test again without the battery?
C23 has been removed.
Noise measured without the battery.
Battery measured noise is nearly the same.
If a test lead is straight. The noise increases. "The use of the battery 40mV" picture!
"if test lead move close to the psu or display. noise will increase."
Reducing the ground loop area, should reduce the noise induced in the.
I do not understand why they have not shielded it internally...
Why not you try to cover the wire of the probe with aluminum foil, seeking a Faraday cage.
Carrington, in my country we say "you get that you paid" (I don't know if there is meaning in english something.
The price of this oscilloscope when it was "young" was over 1500 euros.
But I agree totally with you, fine workmanship inside.
I think in past the TomC searched about this material like your links, I don't know if he found something, but the spray shield coating....yes they like me very well...
The ground noise is not legacy of Owon. Eight years old Tektronics you had more gnd noise that the initial SDS gnd noise. But I haven't any other experience with digital oscilloscopes only with analogues.
Carrington, in my country we say "you get that you paid" (I don't know if there is meaning in english something.
The price of this oscilloscope when it was "young" was over 1500 euros.
But I agree totally with you, fine workmanship inside.
I think in past the TomC searched about this material like your links, I don't know if he found something, but the spray shield coating....yes they like me very well...
The ground noise is not legacy of Owon. Eight years old Tektronics you had more gnd noise that the initial SDS gnd noise. But I haven't any other experience with digital oscilloscopes only with analogues.
Well I have already purchased this: http://uk.farnell.com/kontakt-chemie/emi-35-200ml/coating-conductive-emi-35-200ml/dp/2142398
I will show the results, when I have everything ready, I hope that Aidetek keep his word.
I could use an antistatic bag, only to test.
http://www.hollandshielding.com/226-Transparent_foil-en.htm
But the ferrite in the flat cable of the TFT eliminates much noise.
Your mystery is like "Mitos of Ariadnes" (from Greek Mythology) same psu, identical adapter but the noise is differente, but remaining the answer of Flash2light what is marking of U2 in ver. 3.3. Probably, there is a difference there...Well that's not too bad, I'll be more scared to look around for the answer if it resembled the story of Medusa, it wouldn't be cool turning to stone.
There are a couple of things I've been thinking about. I took a real good look at my new PSU board and discovered that one of the new decoupling capacitors is probably missing. There is no capacitor where C23 is supposed to be. C23 is supposed to be at the end of the adapter board connector. I see glue residue, as if the component was there but fell off during the soldering process. However, I don't think this would cause such a big difference in noise by itself.
Flash2light, can you tell me if this capacitor is present on your PSU board?
The other thing I've been thinking about is that I don't have the battery option. With a battery installed you have additional filtering for the 8.4V supply. The battery itself can act as a super capacitor. I don't know for sure if the results from dgmoore78@yahoo.com and Flash2light were obtained with the optional battery installed.
dgmoore78@yahoo.com and Flash2light, can you clarify this, and if possible, if your test was done with the battery installed, can you do the test again without the battery?
C23 has been removed.
Noise measured without the battery.
Battery measured noise is nearly the same.
If a test lead is straight. The noise increases. "The use of the battery 40mV" picture!
"if test lead move close to the psu or display. noise will increase."
Carrington, the flat cable ferrite came with my scope, I don't know what the effect is if it's not there. The ferrite I was talking about is on the 2 wire cable from the adapter to the TFT backlight LED's. You can't see the ferrite itself on the photo because it's inside the blue shrink tubing.
Carrington, the flat cable ferrite came with my scope, I don't know what the effect is if it's not there. The ferrite I was talking about is on the 2 wire cable from the adapter to the TFT backlight LED's. You can't see the ferrite itself on the photo because it's inside the blue shrink tubing.
Mine does not have that ferrite.
TomC to mine if I put a small ferrite on the cable going to the TFT LED's there is no any reduces at the radiation, perhaps the various decoupling at the Led Drive Circuit works and ferrite can't to help any more.
Your mystery is like "Mitos of Ariadnes" (from Greek Mythology) same psu, identical adapter but the noise is differente, but remaining the answer of Flash2light what is marking of U2 in ver. 3.3. Probably, there is a difference there...Well that's not too bad, I'll be more scared to look around for the answer if it resembled the story of Medusa, it wouldn't be cool turning to stone.
There are a couple of things I've been thinking about. I took a real good look at my new PSU board and discovered that one of the new decoupling capacitors is probably missing. There is no capacitor where C23 is supposed to be. C23 is supposed to be at the end of the adapter board connector. I see glue residue, as if the component was there but fell off during the soldering process. However, I don't think this would cause such a big difference in noise by itself.
Flash2light, can you tell me if this capacitor is present on your PSU board?
The other thing I've been thinking about is that I don't have the battery option. With a battery installed you have additional filtering for the 8.4V supply. The battery itself can act as a super capacitor. I don't know for sure if the results from dgmoore78@yahoo.com and Flash2light were obtained with the optional battery installed.
dgmoore78@yahoo.com and Flash2light, can you clarify this, and if possible, if your test was done with the battery installed, can you do the test again without the battery?
C23 has been removed.
Noise measured without the battery.
Battery measured noise is nearly the same.
If a test lead is straight. The noise increases. "The use of the battery 40mV" picture!
"if test lead move close to the psu or display. noise will increase."Flash2light, when I first looked at your post I assumed that the photo was showing the noise with the scope powered by the grid and the battery removed. However, after looking at the photo closely it seems that the Power ON LED is off. That tells me that you were running the scope off the grid on battery power alone. Is that right?
So now I think that when you say: Noise measured without the battery. Battery measured noise is nearly the same.
It means that the 24mVpp noise photo on you previous post was taken with the scope powered by the grid and the battery removed, and that the noise is nearly the same if the scope is powered by the grid and the battery is installed. Did I get it right this time?
-Powered by grid and battery not installed: noise about 30mvpp
-Powered by battery and grid not installed: noise about 30mvpp
But if the test lead is straight. noise increases more; battery use.
This is ver 3.3 dc-dc board under side.
That's identical to mine (3.2), but yours had the smd capacitor under C34 installed at the factory.
Flash2light, can you read the markings on U2 on your board, on mine I see OBT 2?K CX10. The question mark is a character that I can't make out.
This is ver 3.3 dc-dc board under side.
That's identical to mine (3.2), but yours had the smd capacitor under C34 installed at the factory.
Flash2light, can you read the markings on U2 on your board, on mine I see OBT 2?K CX10. The question mark is a character that I can't make out.
This is new photo lcd backlight dc-dc chip.