Astro Tuner and TX Value

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RADIO43
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Astro Tuner and TX Value

Post by RADIO43 »

Group,

I am wondering if there is a way to turn off or turn down the power to next to nothing using Astro Tuner. I am specifically speaking of the TX High,Mid, and Low Power settings. If I turned all of these down to the lowest possible value will it just TX in a few millawatts or is this not possible?

Thanks in advance

Radio43
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Re: Astro Tuner and TX Value

Post by radio-link »

RADIO43 wrote:Group,

I am wondering if there is a way to turn off or turn down the power to next to nothing using Astro Tuner. I am specifically speaking of the TX High,Mid, and Low Power settings. If I turned all of these down to the lowest possible value will it just TX in a few millawatts or is this not possible?

Thanks in advance

Radio43
Of course this is possible, I just do not know how low the power is - I guess something like 100mW should be possible. But why not give it a try? Note down the old values, then nothing can go wrong.
regards - Ralph, dk5ras

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Ralph A. Schmid http://www.bclog.de [email protected]
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tvsjr
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Post by tvsjr »

I've never tried it, but beware that many PAs, depending on their construction, do Bad Things if you turn the power down too much (you might create a broadband noise generator if you're not careful)...

I'd suggest you look at the output with a spectrum analyzer after tweaking on it, just in case.
mike m
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Post by mike m »

Mot doesn't recommend going below around 400milliwatts due to the power amps going spurious below this level. 100 milliwatts would definitely not be recommended.
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Post by radio-link »

mike m wrote:Mot doesn't recommend going below around 400milliwatts due to the power amps going spurious below this level. 100 milliwatts would definitely not be recommended.
Interesting to know. I never dod go below 500mW, without any spectral abormal behaviour, but I will do some tests when I have some more time :)
regards - Ralph, dk5ras

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Ralph A. Schmid http://www.bclog.de [email protected]
Tel./SMS +49-171-3631223
tvsjr
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Post by tvsjr »

Not that it's a portable, but 110-watt X9000 power amps tend to get weird under 60 or so watts of output... same basic premise on portables, just less power (I could go on about transistors, Q-points, and all that, but it would bore everyone and bring back memories of Electronic Circuits I <shudder>).
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