Pluto manual gain setting

Also known as ADALM-PLUTO.
Jean
Posts: 81
Joined: Sat Sep 05, 2020 8:49 pm

Pluto manual gain setting

#1

Unread post by Jean »

Simon asked to post the issue here, I did already post it a few days ago in the Test Team forum.
Simon G4ELI wrote: Mon Sep 07, 2020 10:42 amPlease post this problem in the Pluto forum if you haven't already done this, add a full logfile. From memory the maximum allowed value may be 49 but it's been a long time...
So here it comes again, I deleted the original post in the Test Team forum, as there has been no reply so far.

---------------------------------------

With RX Gain set to 'Manual', I experience an issue on first start of the radio after Pluto has been powered up. While manual gain is set to 50, the gain appears to be set way higher. Changing the gain with the slider immeadiately sets the correct gain. The issue is reproducible and happens only on first start of the radio after powering up the Pluto.
An error "Radio PlutoSDR> Error writing Channel attribute hardwaregain = 50, error 95, Unknown error" is recorded in the logfile. Hardwaregain can then be incremented up to 73dB without generating further errors. May be related to some missing first-time initialization.
The issue only happens when the RX Gain is set to "Manual" and it is independend on the visual gain setting.

73 Jean DJ0VL

PS: I experienced the issue in previous versions as well.
Attachments
Screenshot-2020-09-06-111622.png
Screenshot-2020-09-06-111630.png
SDR Console tmp.txt
(43.59 KiB) Downloaded 33 times

Manfred,OE3SFU
Posts: 5
Joined: Wed Aug 19, 2020 7:31 pm
Location: Wolfsgraben, Austria, JN88bd

Re: Pluto manual gain setting

#2

Unread post by Manfred,OE3SFU »

Hi,Jean,
I am experienced this problem also - sometimes on my i5/4430 ,8Gb ram intel pc ( cpu load ~8 to9%)and never,so far, on my minix n42c-4( 4x1,1 - 2,5Ghz) (cpu load~10 to15%) if this occurs I stop console and start again . It never occurs then again if I start/stop console.
I also wanted to find out where the problem comes from but maybe this comes from the bootsequence of pluto......but why on the intel i5 pc and never on the minix?

Hope this is of some help for you......

73,Manfred,OE3SFU

Jean
Posts: 81
Joined: Sat Sep 05, 2020 8:49 pm

Re: Pluto manual gain setting

#3

Unread post by Jean »

Manfred,OE3SFU wrote: Thu Sep 10, 2020 1:09 pm Hi,Jean,
I am experienced this problem also - sometimes on my i5/4430 ,8Gb ram intel pc ( cpu load ~8 to9%)and never,so far, on my minix n42c-4( 4x1,1 - 2,5Ghz) (cpu load~10 to15%) if this occurs I stop console and start again . It never occurs then again if I start/stop console.
I also wanted to find out where the problem comes from but maybe this comes from the bootsequence of pluto......but why on the intel i5 pc and never on the minix?

Hope this is of some help for you......

73,Manfred,OE3SFU
Hi Manfred,

Thank you for the interesting info. Yes indeed, the issue just occurs on the first start of the radio after booting the Pluto. I did not yet test different PCs, I just tested with the Pluto directly attached via USB and the Pluto attached via LAN, which does not make any difference. The issue is 100% reproducible on my i7 running with ~5% cpu load.

When using the automatic gain settings, the issue is masked, but the Error 95 is logged nevertheless. Maybe the sequence of the commands "Error writing Channel attribute hardwaregain" and "Set Channel attribute gain_control_mode" plays a role?

73 Jean DJ0VL

Manfred,OE3SFU
Posts: 5
Joined: Wed Aug 19, 2020 7:31 pm
Location: Wolfsgraben, Austria, JN88bd

Re: Pluto manual gain setting

#4

Unread post by Manfred,OE3SFU »

Hi Jean,
I dived not very deep in this problem.At this time I am very busy to push our garden in the autumn mode(hihi) . But in a few days I will spend more time on the hamradio playground,then I'll doing some more test's
Please keep us informed if you find a solution!
Thanks, 73,Manfred, OE3SFU

Jean
Posts: 81
Joined: Sat Sep 05, 2020 8:49 pm

Re: Pluto manual gain setting

#5

Unread post by Jean »

Hi Manfred,

There is no big progress so far. My current workaround is to set the manual gain to 71 (and visual gain to 0), as this seems to be the default setting of the Pluto after power on. With this setting, I do not need to fiddle around with the gain slider to get a usable display setting. With the low dynamics of the signals on QO-100, a harware gain of 71db seems to be ok.

In case of Simon reading this by chance: iio_info returns a hardware gain value of 71db when the Pluto radio is started for the first time after power on, independent of the manual gain set in SDR console. Changing the gain or on subsequent starts of the radio (without powering off the Pluto), the gain is correctly adjusted as set in SDR console. This clearly looks like a first time initialization issue.

voltage0: (input)
15 channel-specific attributes found:
attr 0: bb_dc_offset_tracking_en value: 1
attr 1: filter_fir_en value: 1
attr 2: gain_control_mode value: manual
attr 3: gain_control_mode_available value: manual fast_attack slow_attack hybrid
attr 4: hardwaregain value: 71.000000 dB
attr 5: hardwaregain_available value: [-1 1 73]
attr 6: quadrature_tracking_en value: 1
attr 7: rf_bandwidth value: 1050000
attr 8: rf_bandwidth_available value: [200000 1 56000000]
attr 9: rf_dc_offset_tracking_en value: 1
attr 10: rf_port_select value: A_BALANCED
attr 11: rf_port_select_available value: A_BALANCED B_BALANCED C_BALANCED A_N A_P B_N B_P C_N C_P TX_MONITOR1 TX_MONITOR2 TX_MONITOR1_2
attr 12: rssi value: 99.50 dB
attr 13: sampling_frequency value: 1199999
attr 14: sampling_frequency_available value: [1041666 1 61440000]


73 Jean DJ0VL

Jean
Posts: 81
Joined: Sat Sep 05, 2020 8:49 pm

Re: Pluto manual gain setting

#6

Unread post by Jean »

Manfred,OE3SFU wrote: Thu Sep 10, 2020 9:16 pm Hi Jean,
I dived not very deep in this problem.At this time I am very busy to push our garden in the autumn mode(hihi) . But in a few days I will spend more time on the hamradio playground,then I'll doing some more test's
Please keep us informed if you find a solution!
Thanks, 73,Manfred, OE3SFU
Hi Manfred,

A short update in case you are not member of the test team: Meanwhile Simon did fix the issue with the upcoming version 3.0.26.

73 Jean DJ0VL

Manfred,OE3SFU
Posts: 5
Joined: Wed Aug 19, 2020 7:31 pm
Location: Wolfsgraben, Austria, JN88bd

Re: Pluto manual gain setting

#7

Unread post by Manfred,OE3SFU »

Hi Jean, many thanks for your information - recently I've installed the 3.0.26 from 7th Nov. and it works as expected . Since today I'am back in satellite business - mounting antennas etc. it needs alot of time ,i know ! but nevertheless it#s good to be back in fiddling around.....

good Luck,keep healthy,73,Manfred

----and yes I' am in the Test Team......

Post Reply