Receive on multiple bands on RX antenna

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Hi Community

I am wondering whether I should change to a FlexRadio 6500.

Is this scenario possible with the Flex6500:

- I want to watch a number if HAM bands i.e. 40m/30m/20m simultaneously.
- Therefore I want to use a wideband RX only antenna connected to the RX Ant input of the Flex6500.
-
When I hear an interesting station on one of the bands, I want to switch the TX on this band and make contact - but now using the antenna connected to ANT1/2 also for RX.

Is this automatically possible with the Flex6500?

72s

Dietmar, DL2SBA
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Dietmar K

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Posted 2 years ago

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David

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What radio do you have now that you are considering switching from to the 6500?

You can set the RX and TX antennas independently but I don't think it is possible with SSDR to have it change the RX to match the TX when you make a slice the active TX slice. It is probably possible with a third party program like DDUtils that have macros.
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Dietmar K

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Hi David

I'm currently owning an K3. Upgrading it to a 2nd Receiver will cost about €1500,- so I'm thinking about to upgrade to a complete SDR ...

//Dietmar
(Edited)
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Dietmar K

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Hi David

I've looked at DDUtils - seems to be a powerfull tool. I will read a little bit ...

//Dietmar
(Edited)
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George Molnar, KF2T, Elmer

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One approach that might work is to create as many slices (up to 4) as bands you're interested in monitoring with your wideband antenna. Since the 6500 allows reception only on one antenna at a time, each slice will be on the wideband antenna. You can, however, assign ANT1 or ANT2 (or XVTR) to individual slices without affecting the others. So, if you have the RX antenna, a 40m dipole, and a 10/15/20m tribander, you could monitor all at the same time and have the "correct" transmit antenna selected for each slice, ready to go.

Would that work for you?

Of course, the 6700 is the way to go if you want two essentially independent systems under one roof. Would probably be the best way to go for doing things like monitoring 6m for openings while operating on the lower bands using optimum antennas for both.
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David Warnberg

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You mean like this?  4 slices all different bands, all receiving... notice the TX button on 17 meters?  Thats is where I'd transmit, to transmit on another band simply enable TX on that band.
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David

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I think he is meaning more like this image with the additional behavior of when he selects one for transmit the receive antenna for that slice only matches the the same antenna that is selected for transmit. After experimenting I realized that is not possible since there is only one receiver in the 6300 and 6500 the receive antenna selection is applied to all slices. The 6700 has two receivers and this may be possible with it. In the USA you could order and try the radio for 30 day to determine if it meets your needs. I don't know if the offer exists outside the USA. Maybe something to check with the company you would be purchasing from.

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KF4HR

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Dietmar - Yes, it is certainly possible.  I simply connect a multi-band antenna (160-10M Off Center Fed Dipole) to ANT1 which allows me to watch multiple bands at the same time, then I just select TX on whichever band I wish to work. 

KF4HR
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Andrew Russell

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Dietmar,
That's how I have my 6500. Pixel wide band RX loop on RXA used on all frequencies.
TX antennas on ANT 1 for 80m and up and ANT 2 on 160m.
On the low bands the RX loop is nearly always better than the TX antenna.
Little difference on the higher bands.
Andrew de VK5CV.
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Reg

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Dietmar:

In the summertime out of necessity I run the kind of configuration your are asking about and which Andrew described.  From my station in the south central USA we have a lot of regional lightning from April through the summer months.  On 40/80/160 the noise floor can be S7-S9.  By using a Pixel PRO-1b for receive and a low band antenna for transmitting I have a much more acceptable receive noise floor of S2-S3.  It is simple:  One selects the receive and transmit antennas separately in SmartSDR and when you key the transmitter the antenna switches to the transmit antenna.  Also, I set up TX1/TX2 or TX3 to disable the PRO-1b during transmit.

I'm doing it with a FLEX-6700 but you can do the same thing with a FLEX-6500.

Reg
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Dietmar K

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Good morning to all and thanks for the replies!

If I understood the answers from Andrew-VK5CV and Reg-AA5GI correctly, I can select the RX- and TX-antenna separately for each slice. So I think this is the first step.

Background is, that I'm running an automated tuner HAMWARE AT-502 connected to my K3, which follows the TX frequency.

I assume this will work also for my Flex configuration, but then the control port of the AT-502 must be connected to my PC (virtual CAT port). Whenever I switch a slice to TX the correct TX frequency will be transmitted on the virtual CAT interface to the tuner. Hm - but how does this work, when I'm running the MAESTRO without a PC ... I think I have to dig into the manuals ...

Btw - yes in DL it's also possible to order a Flex and test it for 14 days - we call it "Fernabsatzgesetz" - a pretty bureaucratic name ;-)

//Dietmar