HFU HF Underground

Technical Topics => SDR - Software Defined Radio => Topic started by: ThaDood on October 19, 2024, 1720 UTC

Title: The Ultra-Portable ATS25 max-Decoder Receiver? Updated?
Post by: ThaDood on October 19, 2024, 1720 UTC
https://www.elektormagazine.com/review/ats25-max-decoder-receiver-review   Sound intriguing, but I understand that you'd have to pay for the software upgrades.  Anyone tried this SDR yet?
Title: Re: The Ultra-Portable ATS25 max-Decoder Receiver? Updated?
Post by: jimjack on October 22, 2024, 0704 UTC
Hello,

I had such an ATS25x2, it was a nice device, but had a few minor flaws. I was particularly annoyed by the interference from the LCD display.
The reception with the telescopic aerial was not particularly good.

I later installed the decoder as a kit, but it hardly worked at all. However, this could also have been due to my sub-optimal aerial situation.

I then sold the set again and bought a BELKA. This is a great receiver with its telescopic aerial.
Unfortunately, you can no longer buy it because of the sanctions against Belarus.

Greetings from Germany, Steffen
Title: Re: The Ultra-Portable ATS25 max-Decoder Receiver? Updated?
Post by: RobRich on October 25, 2024, 1918 UTC
Many ATS-25 models ship with "activated" firmware activation keys for subsequent updates, though being realistic, it is more like whatever the developer(s) chose to support in future firmware releases.

The "Max Decoder II" model with the telescopic whip and its low-noise preamp engaged might suffice for casual broadcast shortwave listening, but if anything like the ATS-20(+), plan on adding a reasonable MW/HF antenna solution.

Unless something has changed in recent revisions, I know the ATS-20(+) models usually lack an ESD static protection chip on the antenna input. I suspect it could be the same with the ATS-25 models. You can get a ~$12 "SDR Receiver Guard" device on eBay and similar if not interested in adding an ESD chip or reversed parallel diodes inside the radio.

These ATS-2x models use Si473x receiver chips like the Tescun PL-330 and lots of other portables. The Si473x is a popular choice, just note many radios using it have considerable high-pass filtering in SSB and AM sync modes. Fine for voice, though do not expect much if any bass response for music programming in those modes. I have not really kept tabs on the ATS-25 models, so one might want to check reviews if that is a concern.



I have had a couple of the more basic ATS-20 models; one regular and one plus. The regular model flashed with PU2CLR firmware failed after like a couple of years of moderate usage. My current plus model flashed with ATS_EX firmware is actually an usable little portable if paired with a decent antenna. It is not a weak-signal receiver by any stretch, but a new SWL receiver with basic SSB support for under $30 shipped is a pretty good deal IMO.

https://github.com/pu2clr/SI4735
https://github.com/goshante/ats20_ats_ex
Title: Re: The Ultra-Portable ATS25 max-Decoder Receiver? Updated?
Post by: osiris on October 30, 2024, 2315 UTC
https://www.elektormagazine.com/review/ats25-max-decoder-receiver-review   Sound intriguing, but I understand that you'd have to pay for the software upgrades.  Anyone tried this SDR yet?

I have the Max-Decoder and I really like it for what it is. If you buy the Max-Decoder it comes with the license so firmware/software updates are free. One minor annoyance is when you change bands you sometimes have to fine tune it via the BFO setting.

It decodes FT-8 and CW very well. RTTY and PSK-31 leave a lot to be desired, however.

I think it's a good starter or travel radio. Just my two cents.