RF Output decreasing with operation

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  • Problem
  • Updated 5 years ago
  • Not a Problem
Running the contest this morning, I noticed the RF Output monitored on a LP-100A Digital Vector Watt meter start decreasing slowly as I was using the FLEX 6500.  I was not changing any frequency or mode of operation. However, the RF Output slowly decreased downward a few Watts.  Also, I noticed the same RF Output decrease using Digital modes. Retuning the FLEX Auto Tune did not effect the Output.  This seems to have started with the new SmartSDR 1.2.1 upgrade..
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W4EY

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Posted 5 years ago

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Ernest - W4EG

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Have you check your power supply?

Your AC voltage may be dropping and this may cause your output power drop.

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W4EY

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Ernest: Thanks...Yes I monitor my DC Supply. It Has 55 Amp capability so it should be sufficient. This issue just started with the new SmartSDR version. The FLEX appears to stabilize at 4 watts down from the initial RF output when this starts. Did not notice this in the earlier SmartSDR versons.

Will keep a eye on this..To see if it continues.

Thanks 

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Tim - W4TME, Customer Experience Manager

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As the radio warms up, the RF output will decease a little and it looks like this is what you are observing.  I do not think this is a problem with just a drop of a few watts.  Also check your power supply for a voltage drop while transmitting; it needs to be 13.8V at the radio when transmitting to get full power output.
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W4EY

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Tim, Thanks. I will watch it for a few weeks. This was just noticed after installing the Updated SDR. I have monitored the DC supply output Volt meter and it does not change when transmitting. My setup is running an external Auto Tuner which is tuned with less than 5 watts set on the FLEX Transmit setup panel. However, after tuning the antenna, I show reduced power if I rset the FLEX in BYP instead of setting the FLEX to ATN. My first step is to tune the antenna external tuner with the FLEX in the Tune position. Then I can switch the FLEX to BYP or ATN with no change in the antenna tuning.
 I will keep a eye on it. Possibly is me trying to be Critical. As we know "Change never hurts anyone or anything"  so I will get use to the RF changes.   Thanks
Again.
Bill
Tennessee Vol
(Edited)
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Tom

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For me, it never exceeds 80W according to its own wattmeter!! Power supply seems ok, holding 13.8V stable. Tune or CW signal into fully resonant antenna and SWR @ 1.0 in bypass mode or antenna with SWR @ 2.5 tuned with internal tuner, doesnt make a difference. Same for all bands. What this could be?
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Tim - W4TME, Customer Experience Manager

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Tom - please submit a HelpDesk ticket so we can investigate this issue further.