PLL Progress

Posted on August 15, 2025 by Kevin

I have an ongoing project to compare some PLL Superhet radios I have, a Grundig G4000A, Kaito KA-1101, Sangean ATS-909, Tecsun PL-660 and Tecsun PL-990. I’ve had some bad luck with my last TWO visits to the park, interrupted by lawn mowing. Things are moving slowly, but I am collecting impressions.

I went out on the patio about 14:05 UTC (10:05 AM EDT) here in Palmyra, Virginia, with the purpose of comparing the group. I typically start any comparison process like this by doing a quick band scan with my Qodosen DX-286 because I want to see what’s on the air before getting all the radios out to test. I use that radio because its scans are fast, sensitive and accurate.

Continue reading →
Posted in Radio | Tagged , , , , , , , , | Leave a comment

Radio Ghosts and Other Things that Go Beep in the Night

Posted on August 11, 2025 by Kevin

Images

My first shortwave radio was a Nanaola 10NT504, a receiver that uses superheterodyne technology. In that mode, a radio is tuned by mixing the incoming radio signal with a locally generated variable frequency carrier signal (from a variable frequency oscillator or VFO) in a “mixer” stage, producing two output signals equal to the sum and the difference of the two originals. Those are passed on to a filter tuned to one fixed frequency (often 455 kHz) called the intermediate frequency, which is then amplified, demodulated into audio, amplified again, and sent to a speaker. The VFO signal can be on the high side or the low side of the incoming signal, but in most radios it is on the high side, or 455 kHz + the desired frequency for receiving.

Continue reading →
Posted in Radio | Tagged , , , , , , , , | Leave a comment

Si4732 ATS Mini Firmware 2.30

Posted on August 10, 2025 by Kevin

This is an update to my 2.28 installation post: ESP32 – Si4732 ATS Mini: Firmware Upgrade 2.28 (Updated).

There’s a bit of a wrinkle with this installation that I didn’t have before. The method of storing settings has changed, which basically means that you lose your settings, including Wi-Fi credentials, after the update. Further, the radio will not boot automatically on power up the first time.

After completing the standard update (see my article linked above), power the radio off then while holding down the encoder wheel, turn it back on. This time you’ll see a message that the settings are being reset. Then release the wheel.

I’ve applied the update both to my V1, V3 and V3S radios.

For details on the changes in firmware 2.30, check out the release notes on GitHub.

Posted in Radio | Tagged | 8 Comments

Incoming Radio: SPARKELEC DP-666

Posted on August 9, 2025 by Kevin

What have I done?

I’m trying a new seller, Banggood. A couple of discount codes handed me this SPARKELEC DP-666 radio, plus accessories for $71.63 including tax, insurance and free shipping.

It’s one of those new TEF6686 chip radios. As one might guess from the stylus, it’s touch screen. No SSB, but claims to be dynamite on FM.

Continue reading →
Posted in Radio | Tagged , , , | Leave a comment

First Impressions: Sangean ATS-909

Posted on August 8, 2025 by Kevin

I wanted to compare a well-regarded analog-tuned radio against modern DSP radios and the Sangean ATS-909 fits that bill.

Sangean ATS-909
Continue reading →
Posted in Radio | Tagged , , , | 9 Comments

First Impressions: Kaito KA1101

Posted on August 8, 2025 by Kevin

My new old stock KA1101 has arrived from eBay seller detroitmetromart, and I was excited to get into the box.

Unboxing

Despite the radio being 20 years old, it really was new old stock and looked like it had just come from the factory. The case was flawless, the display crystal clear, and the radio worked just fine.

Kaito KA1101 Retail Box
Continue reading →
Posted in Radio | Tagged , , , , | Leave a comment

Upping My Game

Posted on August 6, 2025 by Kevin

I have fun comparing radios. I have some “reference” stations like CFRX in Toronto, WWV and CHU that I like to use. I band scan on MW and FM at midday and count the number of stations received. It’s not rigorous and sometimes results aren’t repeatable, particularly on shortwave.

My AI friend 🤖 linked to a video about using a signal generator to test radio sensitivity. It was mostly a review of the signal generator pictured below, and the video wasn’t terribly insightful, but it did set me to thinking about how I test radios and how at the end of so many comparison posts I don’t reach a conclusion. I’m plagued by varying signal levels and background noise.

I have a big comparison in the works between a modern and some older analog PLL radios, and it could really use some help. So enter:

Signal Generator (Product Photo)
Continue reading →
Posted in Radio | Tagged , , | Leave a comment