I wonder why it skips a one dB step every 5 steps.
I wonder why it skips a one dB step every 5 steps.Its not skipping 1dB, its jumping 2 dB.
You should see the results of Power Sweep with its 1db amplitude steps over a 20dB range. Although 1 or more of the steps may have 2 steps lumped together as a 2dB ramp up (probably a Bug).
You can determine if Power Sweep works in your DSA815-TG by connecting a coax cable between the DSA815-TG's 'TG Output' and 'SA Input', and then selecting the following settings:
Preset (Green key), FREQ: 750MHz (the Test Frequency), SPAN: 100Hz, RBW: 100Hz (Required if 10Hz RBW Option is installed), TG: On, TG Level: -20dB, Power Range: 20dB, Power Sweep: On, AMP: Auto Scale, Scale/Div: 2dB, Ref Level: -1dB (or A/R).
You should see the results of Power Sweep with its 1db amplitude steps over a 20dB range. Although 1 or more of the steps may have 2 steps lumped together as a 2dB ramp up (probably a Bug).
You can determine if Power Sweep works in your DSA815-TG by connecting a coax cable between the DSA815-TG's 'TG Output' and 'SA Input', and then selecting the following settings:
Preset (Green key), FREQ: 750MHz (the Test Frequency), SPAN: 100Hz, RBW: 100Hz (Required if 10Hz RBW Option is installed), TG: On, TG Level: -20dB, Power Range: 20dB, Power Sweep: On, AMP: Auto Scale, Scale/Div: 2dB, Ref Level: -1dB (or A/R).
You should see the results of Power Sweep with its 1db amplitude steps over a 20dB range. Although 1 or more of the steps may have 2 steps lumped together as a 2dB ramp up (probably a Bug).
Here's a video of mine not working: http://youtu.be/yRFq4LElbw0
It was shot in 1080p/50fps, it will take a few minutes to show at the full resolution.
I wonder why it skips a one dB step every 5 steps.Its not skipping 1dB, its jumping 2 dB.
You should see the results of Power Sweep with its 1db amplitude steps over a 20dB range. Although 1 or more of the steps may have 2 steps lumped together as a 2dB ramp up (probably a Bug).
video of mine not working:Is there any chance that connecting pins 7 and 8 of U1105 could have effected this function? Although it seems unlikely to me.
You can determine if Power Sweep works in your DSA815-TG by connecting a coax cable between the DSA815-TG's 'TG Output' and 'SA Input', and then selecting the following settings:
Preset (Green key), FREQ: 750MHz (the Test Frequency), SPAN: 100Hz, RBW: 100Hz (Required if 10Hz RBW Option is installed), TG: On, TG Level: -20dB, Power Range: 20dB, Power Sweep: On, AMP: Auto Scale, Scale/Div: 2dB, Ref Level: -1dB (or A/R).
You should see the results of Power Sweep with its 1db amplitude steps over a 20dB range. Although 1 or more of the steps may have 2 steps lumped together as a 2dB ramp up (probably a Bug).
Here's a video of mine not working: http://youtu.be/yRFq4LElbw0
It was shot in 1080p/50fps, it will take a few minutes to show at the full resolution.Have you contacted Rigol about Power Sweep not functioning on your unit?
It is interesting that the only other people here I know of that have reported Power Sweep not working is 'obiter' and 'N8AUM'. There is one thing in common between the three of you, which is the U1105 modification. Is there any chance that connecting pins 7 and 8 of U1105 could have effected this function? Although it seems unlikely to me. Anyway at this time it would to nice to hear from others having this issue that have NOT touched U1105 in their DSA815-TG. I'm very sorry for suggesting this could even be a possibility, and I truly hope that it is not.
video of mine not working:Is there any chance that connecting pins 7 and 8 of U1105 could have effected this function? Although it seems unlikely to me.Is there a preset condition for the tracking gen that is not set??
The Video shows the power drops? Does the output turn completely Off when the Ref Level was set?
It is interesting that the only other people here I know of that have reported Power Sweep not working is 'obiter' and 'N8AUM'. There is one thing in common between the three of you, which is the U1105 modification. Is there any chance that connecting pins 7 and 8 of U1105 could have effected this function? Although it seems unlikely to me. Anyway at this time it would to nice to hear from others having this issue that have NOT touched U1105 in their DSA815-TG. I'm very sorry for suggesting this could even be a possibility, and I truly hope that it is not.
It is interesting that the only other people here I know of that have reported Power Sweep not working is 'obiter' and 'N8AUM'. There is one thing in common between the three of you, which is the U1105 modification. Is there any chance that connecting pins 7 and 8 of U1105 could have effected this function? Although it seems unlikely to me. Anyway at this time it would to nice to hear from others having this issue that have NOT touched U1105 in their DSA815-TG. I'm very sorry for suggesting this could even be a possibility, and I truly hope that it is not.
FWIW, my unit doesn't have pins 7 & 8 connected, so the FRAM is writeable, but it does have the slightly more advanced fix that resets the eight FRAM time bytes on power up.
However, I agree that we need some further evidence from the non-tamperers!
It's not a big deal for me, I have a VNA for measuring this stuff anyway, but it would be good to get to the bottom of this.
I don't understand how a VNA can be used as a substitute for Power Sweep to measure an Amplifier's Linearity?
Yes, I hope we get a resolution to why a few DSA's don't work with Power Sweep. Certainly your U1105 jumper 7/8 fix is very handy to keep the Trial Options active for new DSA815 owners, so I hope that there is no issue there with it. And it seem unlikely.
Have you tried using UltraSigma to send SCPI Reset commands (such as Factory, etc) to the DSA to see if that may clear something up. Its easy to do and the commands are listed in the DSA800 Programing Guide. Or also using the new Sanitation mode in the unit. I recall getting into Power Sweep initially seemed a little flaky to me(?), and now it has been working solid for me. Did I clean something up playing with the Power On issue when applying AC power to the unit, or just zero in on the commands/sequence to use it reliably(?).
Edit with a Question: What does FWIW stand for? It must be something like FYI, IMHO(?). I have been wondering about this for some time now. When I first saw it I assumed you had a random finger/keyboard coordination glitch. 2nd edit one minute later: Never mind, I just figured it out. For Whatever It's Worth
I don't understand how a VNA can be used as a substitute for Power Sweep to measure an Amplifier's Linearity?
My 30 year old 8753A does a power sweep - see http://course.ee.ust.hk/elec518/ampsmeasure_NA.pdf
My 30 year old 8753A does a power sweep - see http://course.ee.ust.hk/elec518/ampsmeasure_NA.pdf
I don't understand how a VNA can be used as a substitute for Power Sweep to measure an Amplifier's Linearity?
My 30 year old 8753A does a power sweep - see http://course.ee.ust.hk/elec518/ampsmeasure_NA.pdfOh Wow, when you said your VNA, I never imagined that you had one of these jewels. At home I have just used a RF Signal Generator and a Tek 496 Spectrum Analyzer to test Amplifier Linearity. At work I used Spectrum Analyzers with Power Sweep, actually they were Network Analyzers.
My 30 year old 8753A does a power sweep - see http://course.ee.ust.hk/elec518/ampsmeasure_NA.pdfThanks Howard
It was interesting to see that the HP Power ramp test was at a fixed (user) Frequency.
and the suggestion to use the frequency of a Frequency Sweep 1db drop point.
Where as the Rigol changes both frequency and power level at the same time.
The HP8753 is able to vary the power level continuously, But the Rigol changes the power level in 1db steps (mostly )
@Howard did you check when the output power drops off during your TG setup?
From your video it looks like the 'Ref level' change, or the video Editing?
So I noticed if you set the scale to .1db/div and sweep is normalized it slowly starts dropping. The picture shows about -.04db drop after 10 minutes. Its been about an hr now and it dropped to -.07db. Will let it run over night and see what happens. Also every couple of sweeps I get a blip than goes away, I think its something with internal clock and sweep timing ? Anybody working on a new keygen for the ones that have the 1.04 bootloader? I sure miss the 10Hz RBW !
It is interesting that the only other people here I know of that have reported Power Sweep not working is 'obiter' and 'N8AUM'. There is one thing in common between the three of you, which is the U1105 modification. Is there any chance that connecting pins 7 and 8 of U1105 could have effected this function? Although it seems unlikely to me. Anyway at this time it would to nice to hear from others having this issue that have NOT touched U1105 in their DSA815-TG. I'm very sorry for suggesting this could even be a possibility, and I truly hope that it is not.
My 815 is a virgin, no mods. It came with 1.09 firmware. I tried with 1.12 with same results. Unfortunately it also came with 1.04 bootloader so am not able to try it with older firmware. I spoke with Rigol and they will exchange unit for a new one once they come in. Because of the strike out west might be a while before new stock comes in.
It is interesting that the only other people here I know of that have reported Power Sweep not working is . . . .
I have an untouched 815TG with firmware 1.09 and boot 1.04 and I have the exact same problem. However, I could not believe that this is a faulty unit and contacted Rigol. I got a response today and confirmation from Rigol that they just found out about this DSA issue. Rigol confirmed that this is a firmware bug with units that contain the newest version of hardware. They further informed me that this would be high priority and is expected to be corrected soon, whatever that means as the issue I brought up months ago with the MSO2k Logic Analyzer section (see other thread) isn't fixed so far.
Thus, the hardware must have been improved to result in that lower noise level as my response curve with an unplugged input looks very similar to that of HowardLong's unit as shown earlier in this thread..
Was that a recent information by Rigol? As stated above, they seem to have found out that it is a firmware bug.
atx
I've looked but have not found a firm answer to several questions
Does the keygen work with the V1.09 or greater of the DSA815?
If it does work should I buy a DSA815 or DSA815-TG? I look like the keys add the TG so I figure I so not need the -TG version
Thank you