SWR is different compered to Antenna Analyzer and Wavenode

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Hallo Flex Friends, a question about swr.
When I measure dipole antenna with antenna analyzer the readout is 1.1:1.

Connect antenna to TS2000 and my wavenode the reading is 1,07:1.

Connect same antenna, same wavenode to FR6400 and the reading is 1.8:1

What is the problem here?

Any ideas fellow Flexers?

73 de SA7AKE Jonas 
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SA7AKE

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Posted 1 month ago

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HCampbell WB4IVF

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Since the 6400 and Wavenode report the same high SWR, it looks like the readings are  correct.  Are you sure the Flex is actually transmitting on 7070 kHz?

Howard


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SA7AKE

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yes 100%
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Al K0VM, Elmer

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Is the SWR the same when using TUNE vs. MOX /DAX ?
A screen shot the included the whole Panadapter might be helpful.

AL, K0VM
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SA7AKE

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Al K0VM, Elmer

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The spectrum display would seem to indicate that there maybe more that one frequency coming from the transmitter and if the antenna is not a dummy load then the SWR indication would is caused by the energy on other frequencies. ( Most antennas have low SWR only at the operating frequency.)   Does the spectrum look the same in TUNE vs MOX/DAX?  Does the FLEX SWR  indicator look normal when using a dummy load?  Does the spectrum look the same with a dummy load connected ?
AL, K0VM
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SA7AKE

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I will examine and get back i the matter, tnx for now!

/ SA7AKE
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WX7Y

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with the RigExpert are you measuring through the WaveNode element inline? and has the RigExpert been recently calibrated with a set of high quality loads, Mine from the factory was off a little bit?

this is kind of weird on the WavNode being different between Radios if there on the exact same frequency as your actually measuring between the WaveNode and the Antenna and NOT between the Radio and the WaveNode sensor.

Start here 
With a Calibrated Load on the output of the WaveNode element and AFTER you Calibrate the RigExpert check the SWR with the RigExpert between the radio's Coax connector and WaveNode element with the calibrated load on the output. 

this will check the coax cable from the radio to the output of the WN element to make sure thing are good to there this will give you a starting point and a reference.

hope this make sense

Bret
WX7Y


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SA7AKE

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Hallo Bret ant tnx for reply. Of course, the radios is on exact same frequency .
No calibration has been done but no problem to fix that.
 On 80m the difference between the rigs and the swr is even more..

When I compere on higher frequencys it seems to be less inaccurate.
What do you think about that?

73 SA7AKE Jonas
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Dudley - WA5QPZ, Elmer

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Jonas,

If you have any coax interconnect cables between SWR sensors, depending on frequency, you will see different SWR readings on each meter. Ray , K9DUR , has a SWR sweep program that will use the 6000 as an antenna analyzer for a full band sweep, then you can save each band and email the results to someone if you like.
http://k9dur.info/downloads/SWRPlotte...

Next time you test , use the “Tune” button for a single tone carrier instead of multiple tones over a wider range of frequencies which would effect the readings in the radio. For the most part, the radio is not too sensitive to SWR below 3:1 .

73,
James
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SA7AKE

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Hallo and tnx James! I will try that out - thanks for informativ answer!

73 Jonas SA7AKE
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SA7AKE

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Update, I have made some measurements with a dummyload and the result is the same. Should the panadapter look like this when tuning with ATU?
Nothing wrong with coax or antennas, this works great with my TS2000. Using a logperiodic from M2.

Same with my dipoles for 40 and 80m, works very good with the Kenwood, Flex can not even tune my 80m dipole.. swr 1.7 measured with my callibrated instrument. 

The pic is with dummyload


Some ideas flexers..?

73 Jonas SA7AKE

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SA7AKE

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I thought it should look like the red marks on this pic when you are using the tuner?

/ 73 Jonas


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Dudley - WA5QPZ, Elmer

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Jonas,

First ,  turn off your PC audio ,   it may be injecting some noise ,  and turn down your panadapter gain,  on the right side of the panadapter.    I think some of the noise on the screen may be computer generated,  but not sure.    I attached my 6700 on the same frequency with an antenna SWR of 2.9 ,  tuned with ATU ..    Should be a little closer to what you should have..   Your ATU will not always tune a perfect dummy load,   It will detect that ATU is not required,  and will drop the ATU out.   The Flex RF deck is good to a 3:1 SWR anyways,  I really do not worry about SWR under 2.5 to one,  a matching device is not gaining anything really ..    Here is my 6700 at 3640 kHz. 

73
Dudley
WA5QPZ


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Al K0VM, Elmer

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Jonas,
  It looks to me like you may have a hardware problem..  Your spectrum does not look normal to me.
With proper vertical scaling it should look more like Dudley's spectrum..   You may wish to try a different power supply before you open a ticket with Flex help desk..  

AL, K0VM
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Craig Williams

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NOTE! I had the same spectrum display on transmit once. All those birdies. Did a remove the DC power reset and they went away. Have never come back.
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SA7AKE

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Ok thanks for the tip guys! The funny thing is that the Flex shows so mutch more swr then the wavenode!!

Erlier in this tread;

When I measure dipole antenna with antenna analyzer the readout is 1.1:1.

Connect antenna to TS2000 and my wavenode the reading is 1,07:1.

Connect same antenna, same wavenode to FR6400 and the reading is 1.8:1

The 80m dipole is impossible to tune at all with the Flex, using the TS2000 and wavenode says 1.7:1 ish and no problem using it without tuning..

Some  ?? here that I would like to sort out. My  FR6400 is brand new and done this from the startup 2w ago.

73 de SA7AKE Jonas 
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John KB4DU

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As above, the first thing to try is a hard (power supply off/disconnect the powerpoles) reboot. I had the same happen once, which the reboot fixed. Never happened again, although there have been other mysterious occurrences, but the power off reboot fixed them too.
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SA7AKE

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Ok, now I have tried power off and reboot but same problem. 
Whats next flexfiends?

73 Jonas SA7AKE
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SA7AKE

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Update!
After FPGA board change radio works fine!
Fault was only in SSB and DIGU visible, AM, CW and FM were ok. 

73 SA7AKE Jonas