HL2 - Output/Drive control functions with PA disabled

Max
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Re: HL2 - Output/Drive control functions with PA disabled

#21

Unread post by Max »

For anyone struggling to see detail in the screenshots I posted in my last message you can zoom in by pressing "Ctrl +" in your browser. The detail is there to see clearly. It's just the shots are a bit wide (screen grab taken across two monitors side by side) and the Forum software sizes it to fit window with no option to zoom in (not that I can see anyway).

Max

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Simon G4ELI
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Re: HL2 - Output/Drive control functions with PA disabled

#22

Unread post by Simon G4ELI »

Max,

Thanks, this is exactly the info I need. I may look at this today - I've just had an unexpected flare-up of gout, painful and hard to concentrate.
Simon Brown :shock:
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Simon G4ELI
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Re: HL2 - Output/Drive control functions with PA disabled

#23

Unread post by Simon G4ELI »

And,

Now I see exactly how I apply the drive. For HL2 I scale the IQ from 0 to 100 (Slider) to -20dB to 0dB, so when the slider is as 0 the drive is -20dB.

Now I know what I'm doing I'll work out the correct (better) logic today. An easy change would be to scale 0 to -40dB. Slightly more complex is to make the scale user-definable.
Simon Brown :shock:
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Jean
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Re: HL2 - Output/Drive control functions with PA disabled

#24

Unread post by Jean »

Hi all,

A bit off-topic, just to note that the same issue affects the drive setting with the Adalm Pluto. The drive scale there seems to be roughly 0.4dB per drive unit. Going from drive 100 to drive 0 reduces the output power by ~40dB (the AD9363 attenuator is able to go down to to much lower level).

Jean

Max
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Re: HL2 - Output/Drive control functions with PA disabled

#25

Unread post by Max »

Simon G4ELI wrote: Wed Jul 28, 2021 6:47 am And,

Now I see exactly how I apply the drive. For HL2 I scale the IQ from 0 to 100 (Slider) to -20dB to 0dB, so when the slider is as 0 the drive is -20dB.

Now I know what I'm doing I'll work out the correct (better) logic today. An easy change would be to scale 0 to -40dB. Slightly more complex is to make the scale user-definable.
Thank you Simon. Appreciated. If I had not been using the low level output to the transverter I would never have spotted it but now I can see in the PA output that even at zero drive with PA enabled it moves my Daiwa power meter by just under a needle's width. Usually would simply be a non-issue. To be honest now I know it's expected behaviour I think it's not a massive issue anyway. It was only the uncertainty of not knowing what was going on that was bugging me.

73

Max

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Simon G4ELI
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Re: HL2 - Output/Drive control functions with PA disabled

#26

Unread post by Simon G4ELI »

Max wrote: Wed Jul 28, 2021 8:33 am
Simon G4ELI wrote: Wed Jul 28, 2021 6:47 am And,

Now I see exactly how I apply the drive. For HL2 I scale the IQ from 0 to 100 (Slider) to -20dB to 0dB, so when the slider is as 0 the drive is -20dB.

Now I know what I'm doing I'll work out the correct (better) logic today. An easy change would be to scale 0 to -40dB. Slightly more complex is to make the scale user-definable.
Thank you Simon. Appreciated. If I had not been using the low level output to the transverter I would never have spotted it but now I can see in the PA output that even at zero drive with PA enabled it moves my Daiwa power meter by just under a needle's width. Usually would simply be a non-issue. To be honest now I know it's expected behaviour I think it's not a massive issue anyway. It was only the uncertainty of not knowing what was going on that was bugging me.

73

Max
Max,

Do you suggest I change the drive to 0 to -40dB so you have more control? 0 to -20dB is the default for most if not all radios.
Simon Brown :shock:
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Do not send me direct e-mail, thank-you!

Max
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Re: HL2 - Output/Drive control functions with PA disabled

#27

Unread post by Max »

[/quote]

Max,

Do you suggest I change the drive to 0 to -40dB so you have more control? 0 to -20dB is the default for most if not all radios.
[/quote]

It might be nice to have some more control yes, because I think quite a few people on the Hermes Group are using the HL2 as a transverter driver using the low level output, and some using full duplex for Sat work etc.

Also did you happen to see the post above by Jean re: Pluto, possibly same issue? Or maybe unrelated?

On the other hand if I'm the only one it bothers then I can live with it I guess. At least I know now why it was happening so it's explained behaviour rather than something spurious.

Max

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Simon G4ELI
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Re: HL2 - Output/Drive control functions with PA disabled

#28

Unread post by Simon G4ELI »

Max,

Just let me know if a new range is needed, for now I'll leave it as-is.
Simon Brown :shock:
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Max
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Re: HL2 - Output/Drive control functions with PA disabled

#29

Unread post by Max »

NP

jdow
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Re: HL2 - Output/Drive control functions with PA disabled

#30

Unread post by jdow »

Label the scale -20 dB on left and 0 dB on the right. Then Bob's your uncle, isn't it?

{^_^}

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