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How to send out a carrier wave to allow tuning of external tuner and amplifier?

Rapidrob Member ✭✭

New to the 6400M. I have a Heathkit SB200 Linear Amplifier inline with the radio and then to a LDG 1KW Pro II antenna tuner. Both require a RF signal with a constant carrier in order to tune both up for normal operation. The HK SB200 takes me about three seconds to tune and the LDG is about the same automatically.

The Heathkit amp is being triggered by a Ameritron 704 device via TX1 Motorola jack and is working as it should.

The LDG triggers as soon as modulation is fed into it, not just closing the PTT.

What is the best way to tune both items and How do I do it? FM, CW, or is there another feature in the radio?

Thank you for any helpful info.


  • KD0RC
    KD0RC Member, Super Elmer Moderator
    edited September 2023

    Hi Rob, the Tune button will do exactly what you want - it sends out an unmodulated carrier, regardless of the mode that the rig is in. You can set the tune power independently of the main power setting. I have a KAT 500 tuner, and it works great at 10 W of tune power.

    EDIT: Sorry, I just realized that you are probably using the front panel. Use the physical Tune button. You will need to look at the documentation to see how to set the Tune Power.

  • Gord-VA7GP
    Gord-VA7GP Member ✭✭

    When I use SSB, the easiest way for me to produce a continuous, adjustable carrier for amp-tuning is exactly as KD0RC says - I invoke "Tune". This allows me a lower-power (usually 10W) to perform initial tuning. But my tube-amp requires full-power to finalize the tuning (plate impedance changes, and therefore the required Pi-Network transformation changes), so I increase the "Tune" power in SmartSDR until I see full output; then I final-tweak the amp (my amp happens to be a tetrode, and includes screen-current ... very sensitive for me to tune amplifier for an awesome match!).

  • Rapidrob
    Rapidrob Member ✭✭

    Thank you for the instructions/ info. I will give that a try.

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