Single antenna operation

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  • Updated 2 months ago
Apologies for what seems to be a very stupid and basic question but how do you use a Flex (6700 in this case) radio with a single antenna?  I have one off center fed dipole and I need to use it for both TX and RX but that seems to be not possible??  When I configure the TX and RX on the same antenna the radio just drops out (RX goes dead) like there is no antenna connected at all.  How do you configure things to use the same antenna for both TX and RX.

I guess I am used to radios where you just connect an antenna to a port and it just works for TX and RX seamlessly.

Up until now the radio has been used as SWL only...

Thanks
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Gary Schulz

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Posted 2 months ago

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George Molnar, KF2T, Elmer

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Should work exactly as you imagine. Start with one panadapter and slice open; that should be the default state. If that doesn't work, a hardware reset will probably cure the matter.

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Peter Porschenova

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Gary, No stupid questions we're all learning!  Is the Flag set to Ant 1 on both RX & TX, and is your OCF using Ant 1 on the Flex.

Peter
W2JV
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Gary Schulz

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OCF is connected to Ant1.  When I switch the TX (red flag) to also use Ant1 the RX drops the antenna connection.  I hear it clicking when this happens.  The RX only receives when I have the RX set on Ant1 and the TX on Ant2 or XVTR.
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David Merchant

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Gary - Make sure you’re not using the RX Antenna input. Just connect your antenna to the Ant 1 port. That way it can be used for both RX and TX.
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Gary Schulz

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It is on the Ant 1 port
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David Merchant

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Then as long as you’re within a ham band, and you’ve selected Ant 1, you should be able to transmit.
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David Merchant

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Also make sure you’re not running under “split” mode.
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Earl

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Only one  radio at a time via a transmission line switch  (or manually change  transmission lines)..   A  "balun" "a is recommenced for use with your center-fed wire antennas.
73m
Earl - N1VP 
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Gary Schulz

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I don't understand what you mean by "only one radio at a time via transmission line switch"?  It is only one radio...
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Gary Schulz

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So my radio is broken since I can't put both the TX and the RX on "Ant 1"?  I am getting even more confused...  I just want to connect my antenna to the "Ant 1" port and be able to use the transmitter and the receiver.  Seems that this is somehow not working.

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Gayle Lawson

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Gary:

The radio should operate as you are trying to use it.

As George KF2T recommended, perform a hardware reset, others have had similar or worse problems corrected by the reset.  Many time the error  is due to a  corrupted profile. If you have more than one  TX or Global profile stored, you might want to try a different profile to see if the radio will recover.    The reset procedure is in the SSDR manual.  If you start a Help Desk ticket, the first thing the Flex representative will ask you to do is a Reset.  A reset will erase your profiles.


Gayle K0FLY
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Gary Schulz

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Thank you for confirming that the radio should work this way.  I just did a reset by holding down the OK button while pressing the power button until I saw calibration (white LED) then let go of the OK button.  Radio appears to do the same thing unless I haven't reset it correctly?
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N9VC

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Hi Gary,

I have a 6700 here. I attached a pic to show you my settings.
Make sure they match and your antenna is connected on antenna 1.
Look at antenna selection box at the left. Make sure the Loop A
is NOT selected. At the lower right, make sure the AGC-T slider
is not on 0. Mine has med (medium) selected and the slider is
halfway. For the heck of it, match my sliders and settings visible
and see if you hear anything.
Maybe a full reset would be in order should you still have problems.



73, Jim N9VC

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Andreas Junge, Elmer

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Gary,

can you attach a screen shot that shows the slice you are using?

Andreas, N6NU
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Gary Schulz

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Here is what I am seeing in a nutshell...  After defaulting the radio ( I have configured nothing), here is a screen shot of the RX signal levels when I have the TX set to "Ant 2" and RX is on the correct "Ant 1" setting...


Now, when I put the TX on the proper "Ant 1" setting (note the config change) I see the RX signal levels tank and I hear a relay switching when I change the setting...


When TX is switched to using the correct "Ant 1" port, the RX seems to be disconnecting from the antenna port...
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N9VC

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Unselect the EQ and PHNE at the top of your radio panel so the RX port is visible.
So we can see some of those settings.
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Andreas Junge, Elmer

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Can you click on the "ANT" button, so we can see what the Loop setting are?

What happens when you connect your antenna to the ANT 2 port? Do you have both RX and TX?

This is bizarre indeed.

Andreas, N6NU

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Gary Schulz

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I am using 1.9.13 SW and I also just confirmed that if I connect the antenna to the port "Ant 2" I get exactly the same problem  The RX will not work when the TX is set to the same antenna port.  In this case the same thing happen using Ant 2! 
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Al K0VM, Elmer

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If you did the reset to factory defaults correctly, it should come up on 14.100 with both TX & RX selected on ANT1.   
I suspect a hardware fault.. Open a help desk ticket with Flex..

AL, K0VM
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Mark Erbaugh

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You should be able to transmit and receive on the same antenna, just like with most radios. Of course you can't receive while you are transmitting. Is that what you are trying to do? When you go into TX the radio connects the transmitter to Ant 1 and the receiver goes silent. When you end transmit, the radio should reconnect the receiver to Ant 1 and reception continues. What is happening for you?
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Gary Schulz

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As requested-

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Andreas Junge, Elmer

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Looks as expected. No loop enabled. 
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Andreas Junge, Elmer

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Your firmware version is quite a number rev's back. 

I would upgrade to at least 2.4.9. 

If that does not solve it then I think it' time to contact Flex. 

73, Andreas, N6NU
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Gary Schulz

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I would rather not spend $200 on an experiment to see if it fixes this situation.  I would think that the radio should work correctly on version 1.9.13.  I am just trying to make sure I am not doing something stupid!
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Bill -VA3WTB

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Gary, it should not be working this way, I would start a help ticket right away and not waste more time.
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Gary Schulz

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Thanks Bill...
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Gary Schulz

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I am not trying to transmit while receiving.  All I am doing is changing which antenna the transmitter is assigned to and it is causing the RX to behave badly.  It is not in transmit mode during these tests.
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Gary Schulz

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I submitted a help request through Zendesk.  I presume that is the place to submit tickets?
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K3SF

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not sure what Zendesk is
but
here is link to use flex radio help ticket



https://helpdesk.flexradio.com/hc/en-us/articles/202118688-How-to-Submit-a-Request-for-Technical-Sup...


paul K3SF

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George Molnar, KF2T, Elmer

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Quick thing to try - with both TX and RX on ANT1, and your OCF dipole in ANT1, try to run the automatic antenna tuner. A reset should have cleared it, but I wonder if an old ATU memory is causing this issue.