RF gain as low as possible on lab599

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1

I purchased the digirig about year ago for use with both the lab599 tx-500 and a yaesu 857d. I asked that it be configured with the 3.3V option. When using with lab 599 I find that I have to turn the RF Gain as low as possible (-51) in order to make wsjtx etc usable. Is this expected? I have included a picture of the board (rev 1.7)

PXL_20221214_234327641
PXL_20221214_2343276411920×1446 79.1 KB

2

What happens with RF gain at the regular level?
Is incoming audio level too high? Did you exhaust the level adjustment range in the Control Panel?

3

adjusting the incoming levels did not seem to change the behavior but will try again with that. When receiving ft8 signals and the rf level is at -51 it is reading roughly 68 - 71 db and the floor is about 50db. Adjusting the rf gain to -25 and db gain goes to 81db and a floor of 60dB. I just went and checked the levels for the digirig device in windows and they are set to 80. This is for both playback and recording.

I moved off of the FT8 frequency to get just the noise floor and did some testing:

  • mic level in digirig properties at 80 with rf-gain at -51, 44 dB
  • mic level in digirig properties at 40 with rf-gain at -51, 34 dB
  • mic level in digirig properties at 0 with rf-gain at -51, 29 dB
  • mic level in digirig properties at 0 with rf-gain at 80, 77 dB
  • mic level in digirig properties at 0 with rf-gain at 40, 66 dB
  • mic level in digirig properties at 0 with rf-gain at 0, 61 dB

I feel like I am missing a setting on the radio or something. I have the mode set to Digital and not USB, preamp and attenuator are off, besides that I am unsure where to look next. I can run the rig with the attenuator on or the levels set super low. Just curious if other folks have encountered this with the lab 599.

Thanks,
Chris
KF5DPX

4

Is AGC checked in custom tab of recording device? It should be off.

5

I am finally getting back around to this and can confirm that the AGC is not checked. I have backed off the mic level and increased the RF gain and it does not seem to be peaking over 75 dB anymore. I currently have the mic level at 50 and digitsl RF gain at the radio set to 0. Thanks for the work that you do!

Chris
KF5DPX

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