The analog input will see whatever you throw at it. I don't see how autoranging would help with that. The original RTX does not have any autoranging, and I have not read any reports of a broken RTX analyzer due to overload. I guess there's some other means of protection.
The RTX can handle up to 150V peak and has overload protection. You have to do really foolish mistakes to brake it.
When overload is detected this is evident at a red LED light up and you hear relay clicking. I assume the source is disconnected until the input voltage is back in range for the chosen attenuation setting.
When overload is detected this is evident at a red LED light up and you hear relay clicking. I assume the source is disconnected until the input voltage is back in range for the chosen attenuation setting.
"... 150 V is certainly enough for all but the stupidest mistakes..."
You have high regards for mankind.
Sadly, the reality is much worse: I once custom built a lab instrument for a specific application. During the final tweaking, I accidentally (of course) probed the input of the instrument into a 230Vac port, in front of my customer! The probe survived, but not the instrument, so I had to work round the clock the following couple of days to make it up, pro bono of course.
You have high regards for mankind.
Sadly, the reality is much worse: I once custom built a lab instrument for a specific application. During the final tweaking, I accidentally (of course) probed the input of the instrument into a 230Vac port, in front of my customer! The probe survived, but not the instrument, so I had to work round the clock the following couple of days to make it up, pro bono of course.
I wouldn't recommend connecting 230Vac to the inputs of the RTX6001! But as mentioned above, it does have overload protection, so in most cases it should protect itself against high voltages, even if set to the sensitive ranges.
Like mbrennwa, I haven't heard of even a single case of a broken RTX6001 due to overload.
I consider overload protection as one of the very important features. You can do a lot with a good sound card, but there is always a risk of destroying it if you are not careful.
I have had one unit in for repair, but that was not related to overload.
Whether autoranging should be default on or off is probably a matter of personal preference. But I agree that it should be possible to switch it off.
Lots of good suggestions for a remake
One suggestion that has come up earlier as well is "Fully Isolated ADC/DAC topology".
This is probably possible, but it does present some challenges and risks, plus additional cost.
What is the use case for this?
Does it really have to be isolated, e.g. to be able to inject signals into circuits operating at voltages above/below ground level?
Or is it to eliminate ground loops?
The older AP's used transformers, but as I understand it, the new analyzers do not and are not isolated.
Like mbrennwa, I haven't heard of even a single case of a broken RTX6001 due to overload.
I consider overload protection as one of the very important features. You can do a lot with a good sound card, but there is always a risk of destroying it if you are not careful.
I have had one unit in for repair, but that was not related to overload.
Whether autoranging should be default on or off is probably a matter of personal preference. But I agree that it should be possible to switch it off.
You could also take over the control and set the gain settings from your software if you wish.
Lots of good suggestions for a remake
One suggestion that has come up earlier as well is "Fully Isolated ADC/DAC topology".
This is probably possible, but it does present some challenges and risks, plus additional cost.
What is the use case for this?
Does it really have to be isolated, e.g. to be able to inject signals into circuits operating at voltages above/below ground level?
Or is it to eliminate ground loops?
The older AP's used transformers, but as I understand it, the new analyzers do not and are not isolated.
@JensH
"You could also take over the control and set the gain settings from your software if you wish."
I know it's possible, but I prefer to have full control by myself.
"One suggestion that has come up earlier as well is "Fully Isolated ADC/DAC topology".
Yes, that was me. It appeared there is some cross-talk, though I'm not sure it's between DAC and ADC or between left- and right ADC, or perhaps both.
At 10V DAC output and one of the two ADC channels short-circuit, some signal leaks into it: a few tens of a microvolt.
In itself not a serious problem, but it is also heavily distorted: about -170dB WRT 10V. Still not a serious problem.
BUT... I'm busy with a setup to measure distortions below -180dB, which is not possible with this amount of (distorted!) cross-talk.
(unless additional LNA's are inserted between the twin-T-filters and ADC inputs, which I prefer to avoid).
So I would be really happy if the left/right DAC's and left/right ADC's are isolated (that means not just stereo converter chips).
Cheers,
E.
( @ the mods: the last post has no Quote button. Why? )
"You could also take over the control and set the gain settings from your software if you wish."
I know it's possible, but I prefer to have full control by myself.
"One suggestion that has come up earlier as well is "Fully Isolated ADC/DAC topology".
Yes, that was me. It appeared there is some cross-talk, though I'm not sure it's between DAC and ADC or between left- and right ADC, or perhaps both.
At 10V DAC output and one of the two ADC channels short-circuit, some signal leaks into it: a few tens of a microvolt.
In itself not a serious problem, but it is also heavily distorted: about -170dB WRT 10V. Still not a serious problem.
BUT... I'm busy with a setup to measure distortions below -180dB, which is not possible with this amount of (distorted!) cross-talk.
(unless additional LNA's are inserted between the twin-T-filters and ADC inputs, which I prefer to avoid).
So I would be really happy if the left/right DAC's and left/right ADC's are isolated (that means not just stereo converter chips).
Cheers,
E.
( @ the mods: the last post has no Quote button. Why? )
So you assume the (distorted) crosstalk happens inside the DAC/ADC chips. Could it happen somewhere else, for example in the analog output / input stages?
I am with you... the gods seem to think that's a feature, not a bug. I tend to disagree.
As a way out just select the part of text you want to quote and a "quote" thingy will appear.
OK, so fully isolated ADC/DAC topology means separate ADC and DAC chips for each channel. That's not a big deal. Rather easy to implement. Will of course add a bit to the cost, but not a major problem. Unless we were to use e.g. ES9038PRO DAC's or similar 
.
I thought it meant galvanically isolated, when I saw it in post # 3,154. That would be more challenging.
Crosstalk can (will) happen inside the chips as well as outside. The crosstalk outside can be controlled to some degree (separation, shielding etc.), but the crosstalk in the chips cannot be controlled, unless you are the chip designer.
.I thought it meant galvanically isolated, when I saw it in post # 3,154. That would be more challenging.
Crosstalk can (will) happen inside the chips as well as outside. The crosstalk outside can be controlled to some degree (separation, shielding etc.), but the crosstalk in the chips cannot be controlled, unless you are the chip designer.
Hi Matthias,
I'm pretty sure it happens at least inside a stereo ADC chip (with a Lynx as well as an RTX).
I won't exclude that other routes are also involved, but how to prove it as long as the cross-talk inside the ADC is chip is dominant?
Thx for the hint.
Cheers,
E.
Hi Jens,
That's what I mean. BTW, putting the two channels of a stereo chip in parallel might also reduce the noise a little (3dB?).
No need for galvanic isolation. Just balanced I/O will do.
Cheers,
E.
Hi soongsc,
There is no service manual for the RTX6001.
I have not encountered this problem before.
I will try to help you solve the problem. Perhaps you can provide some additional information? Feel free to use PM.
Does it depend on the sample rate?
Does it always stop after a few seconds?
Does the input also stop working?
Does it loose the USB connection entirely after a few seconds?
I assume that you have tried to remove power as well as the USB connection.
There is no service manual for the RTX6001.
I have not encountered this problem before.
I will try to help you solve the problem. Perhaps you can provide some additional information? Feel free to use PM.
Does it depend on the sample rate?
Does it always stop after a few seconds?
Does the input also stop working?
Does it loose the USB connection entirely after a few seconds?
I assume that you have tried to remove power as well as the USB connection.
That smells like a software issue. Did you try a different computer or drivers or operating system or playback software?
My RTX works perfectly fine for music playback.
If you have not done so already, you may want to:
disconnect and reconnect the USB cable.
Sometimes synchronisation is lost and audio data blocks start missing. Powering off the RTX switch does not have the same effect as disconnecting the USB cable: the USB module of the RTX is powered through the USB cable.