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E100+RFX: continous garbage after doing some TX

MD
Michael Dev
Fri, Jun 3, 2011 6:46 PM

After I'm done with some timestamped burst Tx operation, I am seeing pretty
high level garbage (15 dB above noise level) continuously coming out from
the TX antenna. It goes away after power cycle but it's always there after I
run my Tx app. Between the series of TX bursts I send, this garbage is not
there. (I do see some noticeable transients before each burst but that's for
another thread.) It shows up only after I quit my app. It seems like there
may be a bug in the TX chain either in UHD or HW.  Is there a way to
completely shut off the Tx chain without powering off the device?  TX power
level is already set to the minimum allowed.

Michael

After I'm done with some timestamped burst Tx operation, I am seeing pretty high level garbage (15 dB above noise level) continuously coming out from the TX antenna. It goes away after power cycle but it's always there after I run my Tx app. Between the series of TX bursts I send, this garbage is not there. (I do see some noticeable transients before each burst but that's for another thread.) It shows up only after I quit my app. It seems like there may be a bug in the TX chain either in UHD or HW. Is there a way to completely shut off the Tx chain without powering off the device? TX power level is already set to the minimum allowed. Michael
JB
Josh Blum
Sat, Jun 4, 2011 8:06 PM

On 06/03/2011 11:46 AM, Michael Dev wrote:

After I'm done with some timestamped burst Tx operation, I am seeing pretty
high level garbage (15 dB above noise level) continuously coming out from
the TX antenna. It goes away after power cycle but it's always there after I
run my Tx app. Between the series of TX bursts I send, this garbage is not
there. (I do see some noticeable transients before each burst but that's for

You may want to try leaving the mixers always on between bursts. See if
this helps: http://pastebin.com/VL1i5GVx

another thread.) It shows up only after I quit my app. It seems like there
may be a bug in the TX chain either in UHD or HW.  Is there a way to
completely shut off the Tx chain without powering off the device?  TX power
level is already set to the minimum allowed.

I wonder is the destructors are getting called. Is there something you
app might be doing that causes things to die in deconstruction perhaps?

Is the following function getting called at deconstruction time?
http://pastebin.com/X3DybRVg

-josh

On 06/03/2011 11:46 AM, Michael Dev wrote: > After I'm done with some timestamped burst Tx operation, I am seeing pretty > high level garbage (15 dB above noise level) continuously coming out from > the TX antenna. It goes away after power cycle but it's always there after I > run my Tx app. Between the series of TX bursts I send, this garbage is not > there. (I do see some noticeable transients before each burst but that's for You may want to try leaving the mixers always on between bursts. See if this helps: http://pastebin.com/VL1i5GVx > another thread.) It shows up only after I quit my app. It seems like there > may be a bug in the TX chain either in UHD or HW. Is there a way to > completely shut off the Tx chain without powering off the device? TX power > level is already set to the minimum allowed. > I wonder is the destructors are getting called. Is there something you app might be doing that causes things to die in deconstruction perhaps? Is the following function getting called at deconstruction time? http://pastebin.com/X3DybRVg -josh