FLEX-6300 and problems with THP HL550fx amplifier

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  • Updated 3 years ago
Greetings. Enjoying the FLEX-6300 and Smart SDR 1.6.17. This is real treat since I've been using my FLEX-3000 without issues for about 3 years now. Now that I am able to connect the  6300 (ESET Security was blocking) and got a chance to play with Smart SDR, I decided to hook up my THP HL-550fx amplifier to the 6300.  When I tune with anymore than 10 watts the amp overdrive circuit kicks in (never had this problem with the FLEX-3000). It also kicks in with SSB with the power set at less than 50 watts talking in a "normal voice".  I played with software settings, referring to the Smart SDR manual and tried many different combos, but the amp still kicks off. I have RCA plugs going to the amp from the rig in the PTT and ALC. I was a tad worried that I might have done something to the amp and hooked it back up top my FLEX 3000 and it works fine. Any suggestions. Thanks. 
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dan

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Posted 3 years ago

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Jim Gilliam

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Have you tried hooking the amplifer to a dummy load to exclude any RF issues?


Jim, K6QE

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EA4GLI - 8P9EH - Salvador

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Make sure you are using the right rca connectors in the back. The tx and alc are NOT together.

You should connect to TX (not PTT) and ALC.

(Edited)
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dan

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Salvador. I think you may have something there. I had the cable in the PTT for some reason. I will try and get back. Thanks for all the quick replies.

KH6DAN Dan.
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dan

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That was it. I had the cable in the wrong hole. Thanks again Salvador. Putting out 500 watts again. 73 from San Antonio, Texas. KH6DAN 
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EA4GLI - 8P9EH - Salvador

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Lol, no problem, "been there, done that" no t-shirt though.
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EA4GLI - 8P9EH - Salvador

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Also, I recommend that you avoid ALC altogether.

DDutil works great to set the best power per band on the Flex.
(Edited)
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Cal Spreitzer

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+1 for using DDutil for best power per band!