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Power output instable

 
Edited

Hi Pietro,
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I too had an issue with instable power and swr with my FT-817, which took me quite some time to track down.
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The final unit has some kind of gray shielfing foil on top. With the shielding removed, the power and swr on a dummy load were stable.
After assemling the shielding and the case, the erratic behavior started again.
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In the end an additional insulating piece of a plasic foil between the pa board and the gray shieling foil cured it for my unit.
It may or may not be a solution fo your unit, but it would be a simple try.
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Good luck, 73
Chris
 

I had similar odd readings on my 817N...twice...
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High SWR, odd power and swr readings...turned out it was the finals on their way out.
Thankfully they are relatively cheap and quite easy to replace...but be warned, i replaced mine, all was working perfectly, until i plugged the battery pack back in, then it started all over again...
Yes the finals had blown again...!
I ordered a new power board, but before fitting it i checked the battery pack and one cell had died, seems it dumped the current straight into the mosfets..what a crazy "Undocumented Feature", but since replacing them for a second time, and buying a new battery pack all has been good for the past 2 years or so..
So check your battery pack and don't leave it in there constantly is my advice.
And use some high quality, non conductive thermal paste, mine was very dry which doesn't help moving that heat into the sink.
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Hope that helps
KA6PSD
 

I just put in my order for 2 modules and expected to be in stock mid November?
 

A lot thanks, Al.
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It solved for me: I switched a dozen of times between 6m (rear antenna) and 2m (front antenna) and it solved. I hope forever, but I'm not confident; however I know what I have to look for.
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Pietro I2OIM
 

Gavin, thanks for posting this on your experience with the battery pack issue and destruction of the finals, I have never used a battery pack in my 2001 ft817 and it still has the original finals putting out full power. I will never run an internal pack. This is a fantastic group, every one helping each other. Vy 73? Rick VE1RNM


On Tue., Nov. 19, 2024, 5:05 a.m. Pietro Molina via , <pietro=[email protected]> wrote:
A lot thanks, Al.
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It solved for me: I switched a dozen of times between 6m (rear antenna) and 2m (front antenna) and it solved. I hope forever, but I'm not confident; however I know what I have to look for.
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Pietro I2OIM

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