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Published 20 hours ago • verified publisher icon g0orx

receiver pre-amp

Open human-blip opened this issue 4 years ago • 6 comments

Is it possible to make the receiver pre-amp switchable?

human-blip avatar Jul 26 '20 09:07 human-blip

The preamp can be switched on/off in the Menu->RX

ozy

g0orx avatar Jul 26 '20 14:07 g0orx

I'm not seeing the Preamp checkbox for either of my radios.

First screenshot is for ANAN100 running protocol 1.

Screenshot_20200727_140756

Second screenshot is for ANAN100D running protocol 2.

Screenshot_20200727_140032

human-blip avatar Jul 27 '20 04:07 human-blip

For some reason I though you were using an ATLAS based system. For a Hermes/Angelia card the preamp on/off is disabled and the attenuator is used instead. Setting the attenuator slider to -20dB is the equivalent to turning the preamp off.

g0orx avatar Jul 27 '20 08:07 g0orx

Applying attenuation makes an audible difference but does not change levels on the S-meter or the panadapter or waterfall.

human-blip avatar Jul 27 '20 10:07 human-blip

The receiver preamp is not switchable in all these radios except the first-generation boards. The hardware simply is not there. Therefore you do not get the choice in the menus, doesn't this make sense? -- 73, dl1ycf.

dl1ycf avatar Aug 14 '20 15:08 dl1ycf

BTW, using a preamp or an attenuator does not change the real signal out there in the air, so this SHOULD NOT change S-meter and panadapter readings. A -73 dBm signal from the antenna jack should display as -73 dBm no matter what you do with preamps and attenuators (some programming effort went into this!).

dl1ycf avatar Jan 26 '21 15:01 dl1ycf