Transmit power limited to 3W

F4INE
Posts: 5
Joined: Fri Jan 22, 2021 7:33 pm

Transmit power limited to 3W

#1

Unread post by F4INE »

Hello,

I've bough a HL2 but I face issue with SDRConsole regarding the output power.
Basicaly i can't have more than 3W of output but I got 5W using Quisk.

I've tried to understand why and inspected network packet between my computer and my HL2 and I discovered that the "drive level" is set to 240 (max is 255) and I didn't find any view to change it.

I know there is a slider in TX DSP + config per band but even when I change the slider / config per band SDRConsole still send drive level 240 to the HL2.

Here is the both doc I used to understand the packets content :
-https://github.com/TAPR/OpenHPSDR-SVN/b ... _V1.60.doc
-https://github.com/TAPR/OpenHPSDR-Firmw ... umentation

In the "USBprotocol....." file, it's written :
" When using Hermes or PennyLane the Transmitter output level is set by the drive level value (C0 = 0b0001001x, C1 = 0x00 to 0xFF) and not by the amplitude of the I&Q signals. These are held to a peak value of +/-1.0 by AGC action in the PC DSP code. When using Penelope the amplitude of the I&Q signals controls the output level. Set the drive level (C1) to 0x00 when Penelope is selected and whilst the transmitter is not active."

I'm a bit confused because when i move the drive slider to the left it lover the power ouput (even if the drive level remain the same) so it looks like the "Penelope" way to do not the "Hermes" one.

Could you please infirm / confirm my assumptions ?
Did I miss a screen to set the drive level ? If not is it planned in a next release ?

Thank you for the amazing job you done.

73's, F4INE Nicolas

Max
Posts: 858
Joined: Thu Aug 13, 2020 9:47 am

Re: Transmit power limited to 3W

#2

Unread post by Max »

Hi Nicolas

I think you may possibly have found an issue here. With HL2 On Daiwa power meter into dummy load, I can see only 4W out in SDRC either with CW key down, Tone mode (single tone, 700 Hz or 1 kHz), or Tune mode (OP Power and Drive sliders at 100%, also Audio Gain 100% for Tone mode, ALC shows exactly 100%). Same max power out in each mode, just 4W.

Switched to Spark SDR. In tune mode or CW I see full 5W out on power meter.

Simon, I wonder if this relates to the lower than expected power out on HL2 that we discussed many months ago on the IO Group when HL2 was newest addition?

Max

F4INE
Posts: 5
Joined: Fri Jan 22, 2021 7:33 pm

Re: Transmit power limited to 3W

#3

Unread post by F4INE »

Hi Max,

Do you have the thread of the IO Group ?

73's

Nicolas

Max
Posts: 858
Joined: Thu Aug 13, 2020 9:47 am

Re: Transmit power limited to 3W

#4

Unread post by Max »

Hi Nicolas

The thread actually related to seemingly low drive in voice mode SSB and was in the Test Team group. Simon changed the ALC behaviour which did help, but I cannot say for sure this was related to the issue you have found without going back to old kits to verify. I think maybe it is better not to confuse the two issues as this may be something entirely unrelated, but I do confirm same findings as yourself regarding low power output even on Tune. I am sure Simon will look at it.

73

Max

F4INE
Posts: 5
Joined: Fri Jan 22, 2021 7:33 pm

Re: Transmit power limited to 3W

#5

Unread post by F4INE »

Thank you for the information, if I Can help don t hesitate :-)

Max
Posts: 858
Joined: Thu Aug 13, 2020 9:47 am

Re: Transmit power limited to 3W

#6

Unread post by Max »

Hi Simon

Hope you do not mind me drawing this thread to your attention as I think it was posted about the time your builders arrived and I wonder if you may have missed it? Any chance of a view/comment to the initial post by F4INE? As commented above, I also observe similar behaviour i.e. lower carrier/Tune max power achievable from HL2 compared to other progs like Spark for example.

Many thanks

Max

F4INE
Posts: 5
Joined: Fri Jan 22, 2021 7:33 pm

Re: Transmit power limited to 3W

#7

Unread post by F4INE »

Hello,

Is there any news regarding this behaviour ?

73' F4INE

Max
Posts: 858
Joined: Thu Aug 13, 2020 9:47 am

Re: Transmit power limited to 3W

#8

Unread post by Max »

Hi Nicolos

FWIW I would be very interested in Simon's opinion/investigation too on this one.

Simon, sorry to hear that you had the dreaded CV19. Had not realised. Think this post possibly posted around that period? Hope you feeling fully recovered?

Max

F4INE
Posts: 5
Joined: Fri Jan 22, 2021 7:33 pm

Re: Transmit power limited to 3W

#9

Unread post by F4INE »

I hope you're well, this bug can wait, health has to be our first priority :)

User avatar
G8VLR
Posts: 58
Joined: Sun Nov 01, 2020 12:11 pm

Re: Transmit power limited to 3W

#10

Unread post by G8VLR »

Any update on power out? I can achieve 5W on Thetis but only 3.5W max on SDRconsole.

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