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8400 with or without the built-in Auto Tuner

Marshall
Marshall Member ✭
in FLEX-8000 Signature Series
My plans are to buy an 8400 in March but I can't decide if it makes sense to buy the built-in Auto Tuner version or the base unit without the tuner. Since I will eventually add an amp the built-n tuner will be useless at that point. I also already have an LDG AT-600Pro II. Will the 8400 automatically tune the LDG Pro II?

Thanks for the help.

Best Answer

  • Stan VA7NF
    Stan VA7NF Member ✭✭✭
    Answer ✓

    My suggestion is to have the flex with the built-in Auto Tuner, primarily for multiple usage environments that preclude using any amplifier and also for potential re-sale. Usage patterns vary:
    Some examples: Emergency conditions using a battery normally preclude power amplifiers.
    Some contests have limited power

    Conversly, your normal antenna design should target your transmission line impedance (coax at 50 ohm) and balance using the appropriate turns ratio (1:1 for dipole, 2:1 for off-centre, 4:1 for loop, 9:1 plus for end fed)

    SWR under 2:1 will loose more power in an ATU than it saves through impedance matching, also under 3:1 will also reflect some power back from the transmitter to the antenna again.

    So: YMMV and try to not need an ATU but keep the contingency available for small adjustments at source.

Answers

  • Marshall
    Marshall Member ✭
    Thanks Stan,
    My thinking pretty much follows yours. I do a lot of antenna experimenting and I have a 40m Dipole I will be putting up in the next few weeks. I am also going to install a DX Commander vertical soon.
    My shack is in a guest bedroom so I am trying to keep it a little low key for when we have company. I'm thinking the Auto Tuner version is the way to go.
    Now I just need to decide if I have an 8600 or an 8400 in my future. Need to compare the features. I would also like to get a Maestro for when I travel down to my Florida home.
    Thanks again.
    W4MKH
  • Marshall
    Marshall Member ✭
    I ordered a Maestro and an 8600 on Valentine's Day.
  • Flexed
    Flexed Member ✭✭
    Marshall, please let us know when you receive it so we can track the delivery time. I also ordered one with the ATU because I like that it can be replaced if damaged in the future, unlike other radios.
  • Marshall
    Marshall Member ✭
    I'll try to remember to update this when it arrives. But they are saying mid to late May for shipping. Weirdly I'm hoping for the latter date as I will be in Florida around Mother's Day.

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