locked Re: Calibrating external amp, CW vs FT8 readings #FT8 #TechnicalHelpQuestion

Bill, WB6JJJ

Thanks Mike,
I doubt it since the ICOM IC-7610 power output without the amplifier is 100 Watts. I need to turn down the power to about 20 Watts before the amplifier output starts to drop from 500 Watts.

On Aug 3, 2022, at 9:31 AM, Michael Black via groups.io <mdblack98@...> wrote:

Perhaps your audio levels from WSJTX to the rig are down 3dB?
Windows playback level at 0dB -- WSJTX at full power -- then adjust audio level to rig (via soundcard or rig menu) to bring up the power.
What rig do you have and do you have a sound card?
My paper on setting audio levels should be of use.https://www.dropbox.com/s/hlt50x44qs2ua1f/FT8Noise8.pdf?dl=0

Mike W9MDB

On Wednesday, August 3, 2022 at 11:23:57 AM CDT, Bill, WB6JJJ <bill@...> wrote:

Being a single tone sent at a time, I don’t understand why my ICOM PW-1 amplifier will transmit at a maximum of 500 Watts in FT8/4.
It will output 1000 Watts key down, CW and RTTY.
I can maybe understand the lower maximum power if there were multi tones.
This 500 Watt issue has been confirmed with other PW-1 users.
Any thoughts?

On Aug 2, 2022, at 9:44 PM, William Smith <w_smith@...> wrote:

8 tones (3 bits), hence FT8, but only one at a time.

73, Willie N1JBJ

On Aug 2, 2022, at 7:56 PM, Dave Mueller AA3EE <dmueller421@...> wrote:
Martin, I thought FT8 transmitted 3 tones simultaneously in the 50 Hz bandwidth, which is why I originally asked the question.
If you're right and it's a single carrier at a time, then I understand everything completely. RTTY is the same, except potentially longer transmissions.

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