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Separate antenna for separate bands ?

Hi ll

I am using the Flex 6500 with SmartSDR version 2.7.6

I have one antenna for 6m, and one antenna for 40/10.

I have VFO A on 50313 and VF0 B on 18068.

I can have transmit antenna on the right antenna for each of these 2 bands, but I cannot have different receive antennas ... This possibility should exist, or am I missing something ?

I mean RX and TX on antenna 1 on 6m, RX and TX on antenna 2 on 17m.

How can I do that ?

Thanks + 73

Paul F6EXV

Best Answer

  • Ted  VE3TRQ
    Ted VE3TRQ Member ✭✭✭
    Answer ✓

    Paul, what you want to do is not possible - the 6500 receives using a single SCU, and thus is attached to one antenna at a time. Only way you can listen to 6 and 40 at the same time is a really broadband receive antenna.


  • Bonjour Paul,

    je ne pense pas que ce soit possible d'émettre simultanément sur 2 bandes avec le Flex 6500 (j'ai le même appareil que vous depuis 3 ans). Recevoir oui, mais émettre je ne le pense pas, à moins que je sois passé complètement à côté de cette fonctionnalité depuis le début !


    Jean-Luc / F5JRC

  • Paul F6EXV
    Paul F6EXV Member ✭✭

    Bonjour Jean-Luc

    Non, c'est le contraire... Je peux bien avoir 2 antennes d'émission différentes, mais pas deux antennes de réception différentes...


    Paul F6EXV

  • VE7ATJ_Don
    VE7ATJ_Don Member ✭✭✭
    edited October 2021

    Hi Paul.. because the 6500 has only one SCU (Spectral Capture Unit), I don't believe you can simultaneously transmit/receive on 40/10 on one antenna port and 6m on the other. Nor can you tell the SCU to receive via one port and transmit on the other. I may be missing something, but when you are on 6m, you have selected Ant1 and that would mean that transmit and receive both use Ant1. And the same would be true for 17m on Ant2. (I don't believe you can have receive on Ant1 and transmit on Ant2, but that's not what you are doing).

    Am I misinterpreting what you want to do?

  • Paul F6EXV
    Paul F6EXV Member ✭✭
    edited October 2021


    What I want to do is not necesarily transmit on both bands, just monitor 6m on one combination of RX/TX antenna (let's say ANT 1) and monitor 17m on the other combination (ANT 2)

    I can have 1 and 2 as TX antennas (the appropriate one for each band), but when I change the RX antenna, it will change both bands to the same antenna. I do not really care about TX, I care about RX on the proper antenna for each of these 2 bands. (as an example, my ANT 2 is 6m only).

    Is this clearer ?


    Paul F6EXV

  • Neil D Friedman N3DF
    Neil D Friedman N3DF Member ✭✭✭✭

    If simultaneous reception on two antennas is critical to you, you might consider upgrading to a 6600 or 6700. Both have two SCUs.

  • Paul F6EXV
    Paul F6EXV Member ✭✭

    Can't afford it right now...

  • Alan
    Alan Member ✭✭✭✭

    Yes, it can be done with a HF/6M Duplexer. Combine the HF and 6M antennas, single duplexer output to the single Flex SCU Receiver / Transmitter.

    Alan. WA9WUD

  • Paul F6EXV
    Paul F6EXV Member ✭✭

    Hi Alan

    Never thought of this option... Thanks for the hint !


    Paul F6EXV

  • Neil D Friedman N3DF
    Neil D Friedman N3DF Member ✭✭✭✭

    I believe the maximum bandwidth range of a single SCU is 14 MHz.

  • Paul F6EXV
    Paul F6EXV Member ✭✭

    OK Neil, thanks ! Good to know.

  • KD0RC
    KD0RC Member, Super Elmer Moderator

    You can still listen to two slices that are spaced further apart than 14 MHz.

    For example, you can listen on 160 M on one slice and 6 M on the other. So if you had a 160 - 6 antenna (or a duplexer and two antennas) you would be all set.

  • Mike-VA3MW
    Mike-VA3MW Administrator, FlexRadio Employee, Community Manager, Super Elmer, Moderator admin

    You can actually listen to 160M and 6M at the same time on a single SCU as the SCU samples from 30Khz to 50Mhz all the time.

    You can't display a 54Mhz wide waterfall / panadapter. You would have to do it on 2 unique panadapters sharing the same antenna. Yes, that can sound confusing. :)

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