As I briefly mentioned in my blog post titled KX3 – The First 24 Hours. I spent a little bit of time experimenting with the iOS App titled PSKer. This experimentation included operating it in an over the air method. Meaning I have no audio cables running between the iPad and the KX3. I’m simply relying on the iPad built-in microphone to pick up the audio signal from the KX3 speaker for receive and using the iPad speakers and the KX3 microphone for transmit. The image below is a snapshot from the PSKReporter website. I’m running 5 watts into a ground mounted Hustler 6BTV. My transmitted audio IMD is –34 as recorded by my KK7UQ IMD Meter in the shack.
Of course, an optimum setup would include some sort of audio interface to directly connect the KX3 and the iPad. While I’m still looking into these options, I’m fairly pleased with the performance in the testing. Also, while I had always envisioned this process to be a bit awkward by having to hold in the PTT mic switch and fumble with typing on the iPad. The KX3 makes this much easier with an XMIT button. I can press the XMIT button on the front of the KX3 and the rig will switch into transmit mode until I press it again. I think this is better than using VOX. All I need to worry about is making sure the microphone is positioned near the iPad speakers and the iPad is near the KX3 speaker. More about the KX3 speaker in just a bit.
While I would not opt to use this setup in the ham shack. I’m thinking this will be perfect for SOTA activations. Again, I think a direct cable solution is optimum, I’ve not seen any schematics or plans anyone has designed to date. At a minimum I believe the iPad needs to receive audio from the KX3 via a cable. During the maiden SOTA activation for the KX3, I realized just how weak the KX3 speaker is in an outdoor environment.
With a light breeze and the KX3 sitting on a foam pad on the ground, I had difficulty hearing stations on SSB. I had to use my ear buds and even those proved to lack the quality when connected to the KX3 (as compared to my 817). Of course, what do you expect with a $2 pair of cheap ear buds. I will look into other alternatives before the next activation.
Final comment on the KX3 speaker. I don’t fault Elecraft. As I mentioned in my blog post titled KX3 – The first 24 hours, Elecraft has stated from the beginning that the quality of the built-in speaker will be compromised due to size and recommended either external speakers or earphones/headphones when using in a noisy environment. I’ve done a little research on the Chill Pill mobile speakers. These have been discussed on the Elecraft Yahoo reflector with mostly positive reviews. Weighing in at a mere 7 ounces, they won’t break my back or take up much room in my pack.
I did some testing earlier to see if I could feed audio from the KX3 into the iPad and the PSKer app. The picture below is the setup I used. The white piece is the iPad Camera Connection kit. This connects to the bottom port on the iPad and provides a standard USB connection. Connected to this (via USB) is a Plantronics USB soundcard adapter. I plugged a short stereo patch cable into the KX3 headphone jack and the other end into the microphone input of the Plantronics USB adapter. I connected a second stereo cable from the KX3 mic jack and the other end to the headphone jack on the USB adapter.This does work. But….
The weak link in this is the connection at the iPad. The iPad Camera Connection kit (the white piece) with the added length (approx. 3 inches) of the Plantronics USB soundcard device makes it hard to keep it all plugged into the iPad. On a SOTA activation I am sitting on the ground and will have the iPad in my lap. I can easily see where the connector will get unplugged. But as you can tell it does work. In the picture below I have my iPad running the PSKer App connected to the Elecraft KX3 via the Apple iPad Camera kit and the Plantronics USB sound card device.
I recently created a YouTube video where I discussed this setup and the items I used to connect the iPad to the KX3. I’m going to continue to experiment with other options and will blog about these findings at a later date. You can watch the video below.
Until next time…
73 de KD0BIK