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Re: Linear RFI

lasse moell
 

If you are using the same antenna and feeder and still only the HLA-305 give you RFI, I would look at the DC parts... maybe the RF sneaks out and affects the power supply or if you are using the same PS for both radio and PA you may try two separate supplies. Or maybe try a car battery to see if this improves the RFI situation.

/Lasse SM5GLC

9 maj 2016 23:27:15 +02:00, skrev nn3v_6@... [elad_sdr_en] :

 

Hi all.

I've seen the recent strings discussing the RM Italy HLA-305.

I too have one, and it is a very nice linear to accompany the ELAD FDM-DUO. Truly a set and forget piece of equipment when operated in the AUTO mode. And a nice complement to a portable set-up.

But I have one issue that eludes my effort to correct the problem.

Any time I operate with the FDM-DUO at 4 watts output or greater, I get a huge amount of RFI in the shack.So much so that the modulation of outgoing digital signals is corrupted.

I've tried anti-RFI measures. I've used toroid coils everywhere in the shack, including power cables and computer cables. NO RELIEF.

I am pretty sure the matter is in the HLA-305, and when I use the FDM-DUO with my Alpha 89 linear, I actually achieve greater power out without a trace of RFI. Nothing. It is quiet as a mouse. By the way, I still am surprised that the alpha 89 works like a happy pupy with the FDM-DUO.

But I'd like to solve the FDM-DUO / HLA-305 RFI problem, as that combination is an excellent portable set-up. Lugging an Alpha 89 around, together with the emergency generator for 220m volts is not a very realistic solution.

Anyone have any ideas as a possible solution?

73 de NN3V
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