Optimizing Power Settings for Elecraft K3S and WSJT-X: A Comprehensive Guide

Understanding the Power Settings on Elecraft K3S and WSJT-X: An Introduction

When it comes to optimizing power settings for the Elecraft K3S and WSJT-X, it is essential to have a solid understanding of the power settings available on both devices, not to mention the operating system. The Elecraft K3S is a high-performance transceiver known for its flexibility and advanced features, while WSJT-X is a popular software program used for weak signal communication modes such as FT8 and JT65.

The power settings on the Elecraft K3S can be adjusted in two ways: the RF power control and the ALC (Automatic Level Control) setting. The RF power control allows you to adjust the output power of the transceiver, while the ALC setting helps maintain a consistent output level by adjusting the gain of the final amplifier. On the other hand, WSJT-X offers a power slider that allows you to adjust the output power directly within the software (I don't recommend).

Elecraft K3S Main Menu and Configuration Settings for DATA A

In my Elecraft K3S I have the KIO3B board (sound card) installed. The USB cable is a simple printer cable going from the K3 to the laptop. The software driver for this is here.

First, you should be using DATA A mode. WSJT-X will set it correctly when connected. Set the K3/K3S MIC SEL to LINE and set the level to about 30 (midrange). This will be done by rotating the MIC knob on the radio. Must be in DATA A Mode to see this.

In the Main Menu check

  1. MIC SELECT = LINE (Rotating the Mic knob adjusts LINE. Mine is set to 30.)

and in Menu>Config check:

  1. LIN OUT = nor 017 +/-
  2. PTT KEY = Off Off
  3. RS 232 = USB
  4. TX MON = nor
  5. KIO3B = nor

Below are some LCD captures of settings I have been using:

Step-by-Step Guide to Optimizing Receive on Elecraft K3S and WSJT-X

To optimize this fantastic receiver for receiving digital modes, follow these steps:

  1. Adjust your 2.7K or 2.8K filter for 3.0K.
  2. Set AGC to OFF. (long press AGC button).
  3. Turn off NB and NR.
  4. Under Menu>Config, LIN OUT = nor 017 +/- (This is the one I adjust to increase or decrease the RX level indicator in WSJT-X.)

In the operating system software adjust the audio level. First, adjust the "Microphone-USB Audio CODEC" setting on your computer's soundcard. Approximately 10% for the Microphone.

Step-by-Step Guide to Optimizing Power Output on Elecraft K3S and WSJT-X

To optimize power output on the Elecraft K3S and WSJT-X, follow these steps:

  1. In WSJT-X, adjust the power slider to the middle of the scale. It is important to note that the power slider in WSJT-X controls the output power of the software, not the transceiver. Use the RF power control on the K3 to increase or decrease power output.
  2. In Windows adjust the Speakers (USB Audio CODEC) to 50%.
  3. Start by setting the RF power control on the Elecraft K3S to a level that matches your desired output power. It is recommended to start with a lower power setting and gradually increase it until you achieve the desired signal strength.
  4. Monitor the ALC meter on the Elecraft K3S while transmitting. The ALC meter should ideally stay within the 4 to 5 bar range, indicating that the ALC is properly controlling the output power. If the ALC meter goes higher than 5 bars, it means that the ALC is limiting the output power, and you should reduce the Line/Mic control (see video). The 5th bar is the “NO ALC” point for the K3/K3S.
  5. Monitor the power output and signal quality while transmitting. Use the WSJT-X software's built-in signal reports, the Elecraft K3S's power meter (external if you have one) and ALC meter to ensure that the power output is within the desired range and that the signal quality is optimal.

Fine-tuning Power Levels for Maximum Efficiency and Signal Quality

Fine-tuning the power levels can help reduce unnecessary power consumption and improve the overall performance of your setup.

One way to fine-tune the power levels is by adjusting the RF power control on the Elecraft K3S. By carefully monitoring the power output and signal quality, you can find the optimal power level that provides the desired signal strength without wasting power.

Another important aspect to consider is the ALC setting on the Elecraft K3S. The ALC setting helps maintain a consistent output level by adjusting the gain of the final amplifier. It is crucial to ensure that the ALC meter stays within the appropriate range while transmitting, as excessive ALC activity can lead to distortion and reduced signal quality. Use the K3/K3S MIC GAIN to refine the LINE level to produce 4 bars solid with the 5th bar flickering on the ALC meter.

Tips and Tricks for Achieving Optimal Power Settings on Elecraft K3S and WSJT-X

1. Experiment with different power levels to find the optimal balance between signal strength and power consumption. My power output while operating portable is between 10 watts and 60 watts.

2. Use the WSJT-X signal reports. These reports can provide valuable insights into the effectiveness of your power settings and help you make adjustments if needed. I strive for signal reports between -12dB and -1dB.

3. Consider using a external power meter to measure the actual power output of your setup. This can help ensure that the power levels set on the Elecraft K3S and WSJT-X are accurate and provide the desired results. I use a Bird power meter to monitor power output and leave the Elecraft K3S meter on ALC to keep an eye on it.

In conclusion, optimizing power settings for the Elecraft K3S and WSJT-X requires a understanding of the available power controls and a systematic approach to fine-tuning. By following the step-by-step guide and implementing the tips and tricks mentioned above, you can achieve optimal power output, maximum efficiency, and superior signal quality in your weak signal communications.

Detailed Video

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Thank You

What do you think? Please comment below if you have a recommendation or questions for me. Whether it's about operating, equipment or anything else, I'd love to hear from you. To stay up to date with Mr. B and I on our travels, follow us at TwitterFacebookInstagram and YouTube. If you have any questions or comments about our journey, we invite you to join the conversation in our comment section here or at YouTube. It not only helps you, but other readers as well! Comments really help this website, so please comment below or on YouTube. I'm incredibly thankful for all of our subscribers–their support makes this website possible. Stay in touch & best 73! – Rich, KØPIR


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I'm an Amateur Radio enthusiast. I love the hobby and experimenting with radios, antennas and software. On my YouTube channel I upload videos on the Icom 7300 and Icom 7610 along with Ham radio software programs. I hope to inspire people to try new things in Amateur Radio.

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