The quality of portable radios

[nd2023]

In 2003 I had one of the best portable radios was the Grundig YB-400. It cost $150. It was pretty big, about the size of a book. It overloaded and had OK selectivity, and used 6 AA batteries.

In 2004 I saw a small (about the size of the Insignia HD radio) Coby radio for $20. It had digital tuning and used the headphone cord as an antenna. It was CRAP. Terrible selectivity with 60 dBu stations splattering 0.4 mHz away and >80 dBu splattering 0.6 mHz away, bad sensitivity and overloaded very easily. It was so bad that I threw it in the garbage.

Then in 2005 I got the Eton E-100 for $100 which was small, about the size of a pack of cigarettes. Had the same performance as the YB-400, but only used 2 AA batteries. That worked well for years (it still does today).

Then the Insignia portable HD radio came out. I got it for $40. It outperformed my other portable radios in reception, and decodes HD. All while only using the headphone cord as an antenna. It even rivals my car radio. Only the strongest signals bleed to the adjacents. Soon after I bought the Insignia I also bought the Grundig G8 and I am very impressed with its performance. The G8 has excellent selectivity, I cannot seem to get a strong non-HD local to splatter on the adjacent channel, and it is more sensitive than my car radio, and has a field strength meter.

I carry the Insignia HD radio everywhere because it's so small yet performs very well. I wonder why it took the advent of HD radio for manufacturers to start making quality portable radios.

 

[w9wi]

I wonder why it took the advent of HD radio for manufacturers to start making quality portable radios.

DSP, I would suggest. Digital signal processing is of course a must for HD Radio. Once you're providing the DSP hardware to handle HD, it costs next to nothing to add the firmware to do digital processing of *analog* signals.

Even if you *aren't* interested in listening to HD Radio, the receivers work *so well* with analog signals they're well worth having.

 

[Play Freebird]

That's the reason -- DSP technology, and the decreasing cost of producing chips that contain an entire receiver (aside from power supply, control interface, and audio power stages) in one or two devices.

If we can just get past this idea that IBOC is the panacea to all of AM's problems, perhaps the chip designers would apply more DSP horsepower to the task of demodulating a conventional analog signal. For example, features such as automatic variable IF bandwidth, impulse noise blanking, synchronous detection (of the cleanest sideband), and ancillary data. Concerning this last feature, there's an interesting article in the latest edition of Radio World about an NAB project called ADDS:

http://www.rwonline.com/article/112210

Note that the BPSK and QPSK data carriers are contained well within the limits of the AM channel, so they shouldn't cause first-adjacent interference -- and I suspect the upper group is transmitted out of phase with the lower group, so most of the noise cancels out (at least in theory) in an envelope detector.

But rather than promoting ADDS as an "intermediate step toward full IBOC", let's just be realistic and let it remain a data channel, similar to RDS. In addition to title and artist, the protocol should allow receivers to find simulcasts of the same content on internet streams, FM, and (if we can pull it off) the 76-88 MHz expanded band.

 

[JohnnyElectron]

I agree on one thing - HD has forced DSP radios into public use for FM - NOW they need to do the same for the AM band. There's no reason that they can't make a nice-sounding AM radio (portable even) that uses DSP, and include the AMAX and AMAX stereo specs.

Also, the AM data (RDS) "ADDS" is stupid as it is NOT compatible with current HD radios! I thought if they only send JUST the call letters/ID, then it made sense, but it does not if it requires a new format - UNLESS, our HD radios can use that 'secret' "SERVICE" JACK on our HD radios to download/upload new firmware for it?

 

[DaveBayArea]

I now have a Tecsun PL-380 and I'm still trying to figure out all of the bells & whistles. It does AM with DSP and variable bandwidth, although it only goes up to 6 KHz. Still, it sounds fantastic for $60. The FM is phenomenal too. In fact it's the first portable radio I've owned that can actually overcome HD interference (on FM) and in some cases allow us to hear stations that were lost due to HD. You have to move the antenna just right, but it actually works. I too have the Insignia (well, mine's a Mighty Red) and I agree that it's good. But the Tecsun is better.

Dave B.

 

[ddsparxx]

I also have the PL-380. I look for a perfect position of the whip antenna to hear a distant FM station hidden under the IBOC hash and there it is.

 

[test123]

I have been looking for an inexpensive radio with a speaker that I can take with me when I travel and the PL-380 looks like it fits the bill.

Where do you buy one? Is eBay the only place?

t123

 

[ddsparxx]

I have been looking for an inexpensive radio with a speaker that I can take with me when I travel and the PL-380 looks like it fits the bill.

Where do you buy one? Is eBay the only place?

t123

Ebay is the only place I know where to get it.

 

[DaveBayArea]

Ebay is the only place I know where to get it.

Yeah, that's where I got mine too. From a dealer in Vancouver. Seems like somebody ought to import 1000 units & sell them. These radios are killer.

Dave B.

 

[JohnnyElectron]

I'm still looking for the "AM" switch on my Insignia HD portable! Also, I would love to be able to kill the HD and keep analog only on the Insignia HD - anybody figure that one out. Here's why:
Local AC FM station has great high end and stereo separation until HD kicks in and the stereo stage goes from 180 degree to 30 degrees and the high-hats and high end goes away! What a price to pay for their cruddy HD2 signal that doesn't even have any PAD into whatsoever!

 

[test123]

Ebay is the only place I know where to get it.

I just ordered one from one of the Hong Kong dealers on eBay. Would be nice if someone in the States would sell them. We'll see how it goes.

t123

 

[nd2023]

The Tecsun PL-380 looks awfully similar to the Grundig G8. Does it have that soft muting "feature"

 

[DaveBayArea]

The Tecsun PL-380 looks awfully similar to the Grundig G8. Does it have that soft muting "feature"

I think so. When the signal falls to something below about 10 dbu on the built-in signal strength meter (super-handy, BTW - I wonder if it's accurate) the audio gets quieter. I suspect that's what you mean. I figure that has something to do with the threshold of the digital detector.

Dave B.

 

[BRNout]

The Tecsun PL-380 looks awfully similar to the Grundig G8. Does it have that soft muting "feature"

I think so. When the signal falls to something below about 10 dbu on the built-in signal strength meter (super-handy, BTW - I wonder if it's accurate) the audio gets quieter. I suspect that's what you mean. I figure that has something to do with the threshold of the digital detector.

Dave B.

They "toned down" the soft muting on the PL-380 as opposed to the obnoxiously heavy-handed muting employed by the G8. Even the PL-310 is less 'muted' than the G8. But the PL-380 supposedly has hardly any soft muting, which has been the cause of good reviews as far as AM reception is concerned. By all accounts, a much stronger performer than the G8 on MW/LW/SW and probably a little better on FM (as is the PL-310).