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M0nka derived SDR-928 finals voltage

codecxbox

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Jul 28, 2021
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on my bench..the mosfets are replaced and upto now its TX per specs..But I was itching to measure voltage but didnt dare to..usually these radios are calibrated by measuring current draw at the DC..anybody would happen to know voltages on the fets?
 

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kopcicle

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Feb 17, 2016
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Well just by noodling around in the attached pdf you can assume a few things.

One pin is of course at or near supply voltage.
The bias that will produce xx`milliamperes will of course vary .
And one leg is at or nearly so, at ground.

Hint look at the the test and adjustment around pg 54 and 81

The reason you're not getting a full description is I'm away from my notes, distracted, busy, would rather teach you to fish in any case, or I'm full of shit :)

Actually Chris embarked on a monumental project and in most ways managed to pull it off. I do recommend that you perform the bias in TX only modification controlled by the ptt.
I also recommend that you get into the menu and turn FM down

If you have a burning desire for a QRP radio then this won't be of any use to you.

https://www.nxp.com/docs/en/quick-reference-guide/MRF101ANEKITQRC.pdf

Of course you'll need a 48-50V supply and an additional band switched LPF on the back end.

While we're polishing a turd ...

https://www.ebay.com/itm/392873830688?hash=item5b791ae920:g:jswAAOSwJdRfDt-M

See what happens when the mind wanders? :)
 

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codecxbox

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Jul 28, 2021
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tks Kop..is was very useful..is 6 watts AM at 20 m ok?
 

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kopcicle

Sr. Member
Feb 17, 2016
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Well,
We'll have to qualify that. A fully modulated 6 watt dead key is 24W . That may be a little much. I mean it's your hot rod. How hard do you want to push ?
 
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kopcicle

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