Topics

Setting audio / power level proceedure

Al Womelsdorf
 

After reviewing the fldigi manual a few times, I am still a little confused about the best method to set the audio output (and hence the actual output power) level.

In one spot it describes a technique of setting the audio level until the ALC level just starts moving, then set your output power via the radio control (I assume). This seems similar to the technique described for WSJTX as well.

An alternate method recommends setting your maximum output power to the highest value your radio allows, then use the audio level to set the actual output power, never to exceed 50% of the radios max capabilities! - presumably by using either the output power meter on your radio, or a peak-hold external power meter. At this point you should never see any movement in your ALC at all.

Personally, I have been using the second method, and typically run between 25 and 40 watts of power. I have also tried setting the power level of the radio to something specific (say 25W), then adjusting the audio level until I see that power level on the external meter. If I do it this way however, my ALC is reaching mid-scale, which would be typical for SSB, but perhaps not the most desirable for this mode. Also it would seem to me that whatever the best method is, it would apply equally to any of these "audio" modes like fldigi, and wsjtx. I also see a decided interaction between the set power level and the ALC, which makes perfect sense to me.

Exact equipment is Fedora Linux, FT-DX3000, Daiwa CN-901 SWR/Power meter, and cat cable used for both rig control and audio. Radio is in Data/USB mode. Latest alpha versions of the software.

Thanks in advance for any suggestions.

73's.

Al
KD2PNR

k4pwo <k4pwo@...>
 

The power level at maximum and adjust audio level for 25 to 50 watts for a 100 watt radio is the correct method.  With my TS-480HX 200 watt radio I can get up to 100 watts output without ALC action.

Perry K4PWO 



Sent from my Sprint Samsung Galaxy S10+.

-------- Original message --------
From: "Al Womelsdorf via Groups.Io" <ahw609@...>
Date: 5/23/19 11:48 AM (GMT-06:00)
To: nbems@groups.io
Subject: [nbems] Setting audio / power level proceedure

After reviewing the fldigi manual a few times, I am still a little confused about the best method to set the audio output (and hence the actual output power) level.

In one spot it describes a technique of setting the audio level until the ALC level just starts moving, then set your output power via the radio control (I assume). This seems similar to the technique described for WSJTX as well.

An alternate method recommends setting your maximum output power to the highest value your radio allows, then use the audio level to set the actual output power, never to exceed 50% of the radios max capabilities! - presumably by using either the output power meter on your radio, or a peak-hold external power meter. At this point you should never see any movement in your ALC at all.

Personally, I have been using the second method, and typically run between 25 and 40 watts of power. I have also tried setting the power level of the radio to something specific (say 25W), then adjusting the audio level until I see that power level on the external meter. If I do it this way however, my ALC is reaching mid-scale, which would be typical for SSB, but perhaps not the most desirable for this mode. Also it would seem to me that whatever the best method is, it would apply equally to any of these "audio" modes like fldigi, and wsjtx. I also see a decided interaction between the set power level and the ALC, which makes perfect sense to me.

Exact equipment is Fedora Linux, FT-DX3000, Daiwa CN-901 SWR/Power meter, and cat cable used for both rig control and audio. Radio is in Data/USB mode. Latest alpha versions of the software.

Thanks in advance for any suggestions.

73's.

Al
KD2PNR

P C Andy Anderson
 

This is the method I use with the TT Jupiter and the SignaLink USB. Works good and lasts a long time.
Andy...W3LI


From: nbems@groups.io <nbems@groups.io> on behalf of k4pwo <k4pwo@...>
Sent: Thursday, May 23, 2019 3:07 PM
To: nbems@groups.io
Subject: Re: [nbems] Setting audio / power level proceedure
 
The power level at maximum and adjust audio level for 25 to 50 watts for a 100 watt radio is the correct method.  With my TS-480HX 200 watt radio I can get up to 100 watts output without ALC action.

Perry K4PWO 



Sent from my Sprint Samsung Galaxy S10+.

-------- Original message --------
From: "Al Womelsdorf via Groups.Io" <ahw609@...>
Date: 5/23/19 11:48 AM (GMT-06:00)
To: nbems@groups.io
Subject: [nbems] Setting audio / power level proceedure

After reviewing the fldigi manual a few times, I am still a little confused about the best method to set the audio output (and hence the actual output power) level.

In one spot it describes a technique of setting the audio level until the ALC level just starts moving, then set your output power via the radio control (I assume). This seems similar to the technique described for WSJTX as well.

An alternate method recommends setting your maximum output power to the highest value your radio allows, then use the audio level to set the actual output power, never to exceed 50% of the radios max capabilities! - presumably by using either the output power meter on your radio, or a peak-hold external power meter. At this point you should never see any movement in your ALC at all.

Personally, I have been using the second method, and typically run between 25 and 40 watts of power. I have also tried setting the power level of the radio to something specific (say 25W), then adjusting the audio level until I see that power level on the external meter. If I do it this way however, my ALC is reaching mid-scale, which would be typical for SSB, but perhaps not the most desirable for this mode. Also it would seem to me that whatever the best method is, it would apply equally to any of these "audio" modes like fldigi, and wsjtx. I also see a decided interaction between the set power level and the ALC, which makes perfect sense to me.

Exact equipment is Fedora Linux, FT-DX3000, Daiwa CN-901 SWR/Power meter, and cat cable used for both rig control and audio. Radio is in Data/USB mode. Latest alpha versions of the software.

Thanks in advance for any suggestions.

73's.

Al
KD2PNR

Curly Frazier <w7lpn.ham@...>
 

I use the second example as well, watching the ALC continuously. It seems to be effective.


On Thu, May 23, 2019, 10:48 Al Womelsdorf via Groups.Io <ahw609=verizon.net@groups.io> wrote:
After reviewing the fldigi manual a few times, I am still a little confused about the best method to set the audio output (and hence the actual output power) level.

In one spot it describes a technique of setting the audio level until the ALC level just starts moving, then set your output power via the radio control (I assume). This seems similar to the technique described for WSJTX as well.

An alternate method recommends setting your maximum output power to the highest value your radio allows, then use the audio level to set the actual output power, never to exceed 50% of the radios max capabilities! - presumably by using either the output power meter on your radio, or a peak-hold external power meter. At this point you should never see any movement in your ALC at all.

Personally, I have been using the second method, and typically run between 25 and 40 watts of power. I have also tried setting the power level of the radio to something specific (say 25W), then adjusting the audio level until I see that power level on the external meter. If I do it this way however, my ALC is reaching mid-scale, which would be typical for SSB, but perhaps not the most desirable for this mode. Also it would seem to me that whatever the best method is, it would apply equally to any of these "audio" modes like fldigi, and wsjtx. I also see a decided interaction between the set power level and the ALC, which makes perfect sense to me.

Exact equipment is Fedora Linux, FT-DX3000, Daiwa CN-901 SWR/Power meter, and cat cable used for both rig control and audio. Radio is in Data/USB mode. Latest alpha versions of the software.

Thanks in advance for any suggestions.

73's.

Al
KD2PNR

David Ranch
 


Agreed.  This method gets you the cleanest RF signal but you need to watch your soundcard levels carefully across reboots, OS upgrades, etc.  If your soundcard's audio output level gets reset to 100%, your radio and man other fellow HAMs on your band of choice will hate you until you discover you're splattering.  :-)

Here is a PPT I put together back in 2016 about the topic:

   http://www.trinityos.com/HAM/index-ham.html#hf-dig-modes-101

--David
KI6ZHD


On 05/23/2019 12:07 PM, k4pwo wrote:
The power level at maximum and adjust audio level for 25 to 50 watts for a 100 watt radio is the correct method.  With my TS-480HX 200 watt radio I can get up to 100 watts output without ALC action.

Perry K4PWO