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Check the antenna Bias Tee first.

Many don't have enough filtering built into them.

Regards,

Martin

Before swapping supplies, make sure that it is the Apple power brick that is causing the problem. It may well be something else.

The signal will most likely change its characteristics if the power supply load is altered in some way.

Try a different make of supply and see if the interference on that frequency changes or goes away completely.

Regards,

Martin

"Seems the interface is a bit slicker."

Not really, it's just different, and has as many "quirks and foibles" as the KiWi (sorry John).

OpenWebRX + is more orientated to the VHF / UHF bands, and is good at the modes that can be found there, and I operate both.

However, the developers are not as responsive as John, and the admin interfaces and configuration processes require a good degree of skill to set them up and make them function correctly.

By contrast, the KiWi works pretty much straight out of the box and is generally stable, OWR+ is more of a work in progress.

This may suit folks proficient in Linux, who enjoy spending many hours resolving problems, but some of us just want something that works, with minimal hassle.

Regards,

Martin

There are so many amateur digital modes these days, it is often very difficult to say what is being used.

It is around the frequencies typically being used for SSTV, and it could be Digital SSTV, but that is just a guess on my part.

The Signal ID Wiki is a good place to start when trying to ID unknown signals.

https://www.sigidwiki.com/wiki/Signal_Identification_Guide

Regards,

Martin

All the broadband routers I have had provided, have had noisy Switched Mode "Wall Wart" type power supplies as standard.

They produced far more interference than the routers, which generally tended to be of good construction and had been EMC tested as part of the design process.

The power supplies always seemed to be an afterthought, and may have been sourced differently from the actual router, depending on local electrical regulations and requirements.

It is likely that the power supplies have been chosen on the basis of cost, and we all know what happens then.

Because of their small size, it is usually not possible to add extra filtering, and such internal modifications can also result in safety and insurance issues.

I tend to look in Charity (Thift) stores or at Car Boot sales for older, cheap electronics, with separate linear power supplies. As it's difficult and expensive to buy new linear power supplies, especially since the audiophiles are willing to pay silly prices for them. The rest of the electronics are useful for parts too.

On an incidental, but related subject

A friend of mine, who allows me to host a KiWi at the historic Goonhilly satellite earth station in Cornwall UK, was good enough to resite the KiWi to a new location on the site, in an attempt to resolve some long standing interference problems. However, he couldn't get it to connect properly to the network. He could see it acquired a DHCP address, but he couldn't ping it. He then transferred the KiWi back to the original location, and it still didn't work properly.

Thinking that somehow the build had become corrupted, we arranged for him to return the KiWi to me, so that I could fix it, upgrade the OS and take the opportunity to check things like the fan (which as expected was stuck solid).

The actual fault was the Switched Mode Power supply, which seemed to be working correctly, as the output voltage was correct when checked with a multimeter, it would also still happily deliver 5A output.

However, I noticed that the output voltage dipped just a bit more than I would have expected when on load, but only by about 0.2v.

I took the power supply apart and discovered that the main high voltage DC storage capacitor (150uF at 450v) had dried out over time, and was completely open circuit. This is why the DC regulation was so poor, and also why the KiWi was having difficulties.

Replacing the capacitor fixed the problem, and the KiWi was back to working as normal.

Most of my past KiWi problems have been power supply related in one way or another, so my rule of thumb now is:-

If your KiWi is misbehaving in any way, check the power supply first, and pay close attention whilst you do it.

Regards,

Martin