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PGXL how hot is too hot?

I just opened a ticket with Flex, but of course it happens to be Friday, just after closing time, so I am posting here just to get some ideas between now and Monday.

 I've only owned this PGXL for ten days and just noticed it is running hot - 50-60 degrees, even though I am on 120V and only pumping 600W. This is on SSB and CW, not digital/full duty cycle. Last night I fished out the "final QC passed" sticker which appeared to be blocking the air intake. I never noticed the sticker before, so assume it must have come loose in packing/shipping from it's intended location on the front of the amp. Anyway, 50-60 degrees seems pretty hot for 600W.  I have adequate spacing front and back of rig. I only noticed this in the last couple of days, but cannot say for certain if the amp has been hot from the start or this is something new. 

F/W is current - 3.5.23. Any ideas?

Rusty - W3US


  • TxPres W5PD
    TxPres W5PD Member
    Try checking Meffa Enabled on the "Other" tab in the configuration menu.
    I find that my PGXL runs a lot cooler when enabled.
  • W3US
    W3US Member ✭✭

    Yes, Meffa is enabled. Thanks.

  • David Decoons, wo2x
    David Decoons, wo2x Member, Super Elmer Moderator

    On SSB mine gets to mid 50s. I have not seen it higher than 58, even when the few times on FT8 at high power.

    It cools down very quickly.

    Dave wo2x

  • KM4CQG
    KM4CQG Member ✭✭


    What Fan mode do you have selected ?

    On FT8 I seldom run more then 10 watts in and nets me 225 watts out and run the Fan on quietest setting.

    I do on longer Key downs see temps in the Mid 50s on SSB but amp cools very quickly.

    Regarding voltage I am running 240 into my Amp.



  • W9WLX_Chuck
    W9WLX_Chuck Member ✭✭

    It will run a bit warmer in AAB mode (used for SSB). Mine runs around 50 for conversational SSB at 600-800 watts on 240v. The rise is slower in AB mode (CW, Digital) but the harmonic load temp rises faster. That is pretty much what I would expect. MEffA is not available for SSB and AM mode. It functions only in AB mode but the display would lead you to believe that it works in both modes.

    Chuck, W9WLX

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


    When you get to 80C or so, then, start to look into your cooling.

    50-60C is normal regardless of your source voltage. And, you are limited to 500 watts or so about 120VAC input.


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