7000DLE MkII PA temp overcompensation?
Posted: Mon Jan 17, 2022 4:24 pm
My 7000DLE MkII (big silver box version with no PC) has an interesting, if minor issue and I'm curious if anyone else has seen it.
The PA bias compensation appears to be over-compensated:
(1) Boot the rig from ambient (cold)
(2) Quickly set the PA calibration [for some band] so that the output power is 100W when the drive slider is at 100%
(3) Key the rig for 30 seconds in TUNE mode, unkey for 30 seconds
(4) Repeat (3) above 10 times
(5) Measure the TX power output, still with the drive slider at 100%
In my case at least, the rig will show something in the range of 88-90W. Let it cool for an hour or two and re-check the TX output power, and the "cold" calibration will be back at 100W.
You might ask "who cares", and you'd be right to do so. For most people in most "real" situations it really doesn't matter.
The exception, of course is that I would like to use the rig for characterizing/testing HF power amps - something I do a lot of.
I have other rigs I can use, but it since the 7000DLE MkII has that nifty RX2, I can monitor the amp output with a sampler and immediately "see" when something isn't right, or what I would expect. It would be very handy to be able to use it.
Has anyone normalized the PA output on their radio?
Thanks!
Jim N7CXI
The PA bias compensation appears to be over-compensated:
(1) Boot the rig from ambient (cold)
(2) Quickly set the PA calibration [for some band] so that the output power is 100W when the drive slider is at 100%
(3) Key the rig for 30 seconds in TUNE mode, unkey for 30 seconds
(4) Repeat (3) above 10 times
(5) Measure the TX power output, still with the drive slider at 100%
In my case at least, the rig will show something in the range of 88-90W. Let it cool for an hour or two and re-check the TX output power, and the "cold" calibration will be back at 100W.
You might ask "who cares", and you'd be right to do so. For most people in most "real" situations it really doesn't matter.
The exception, of course is that I would like to use the rig for characterizing/testing HF power amps - something I do a lot of.
I have other rigs I can use, but it since the 7000DLE MkII has that nifty RX2, I can monitor the amp output with a sampler and immediately "see" when something isn't right, or what I would expect. It would be very handy to be able to use it.
Has anyone normalized the PA output on their radio?
Thanks!
Jim N7CXI