Tecsun R-912 product review

I’ve previously reviewed the Tecsun R-912. Here is the “official compilation” of features that I’m using now for my reviews.

Model Tecsun R-912
Frequency coverage FM 87 – 108 MHz
AM 525 – 1610 KHz
SW1 3.55 – 4.0 MHz
SW2 4.7 – 5.25 MHz
SW3 5.9 – 6.3 MHz
SW4 6.95 – 7.4 MHz
SW5 11.55 – 12 MHz
SW6 13.3 – 13.9 MHz
SW7 15.0 – 15.6 MHz
SW8 17.4 – 18.05 MHz
SW9 21.35 – 21.9 MHz
FM Stereo Yes (earphones)
Sensitivity FM 10 μV
AM 1 mV/m
SW 50 μV
SSB No
Technology Single conversion
Battery 2 AA
External DC 3v Center (-)
External antenna jack No
Tuning Analog
Display Digital
Volume Analog
Signal strength indicator Yes
Whip antenna length 19”
Local/Distance switch No
Bandwidth switch No
Tone control No
Dial light No
Clock No
On/off Slide switch
Control lock No
Attached battery door No
Size 4 5/8” x 3” x 1 1/16”
Weight without batteries 5.9 oz.
Carrying Wrist strap
Accessories included Ear buds, external antenna, pouch
Price (including shipping) $22.55 (eBay)
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An unexpected radio store

Want to buy a shortwave radio? There are several stores. I buy most of mine on eBay. Amazon.com can be a good place. Radio Shack carries a few and you can sometimes get a good deal on a clearance item. Serious shortwave users talk about Universal Radio.

Today I stumbled upon an unexpected source, one that has generally competitive pricing and a few good radios: the NPR Shop. National Public Radio (NPR) sells merchandise to raise funds to support the organization. Naturally folks who listen to NPR are at least somewhat interested in radio, so it makes sense. There are shortwave radios from Grundig/Eton and C Crane. They have some Sangean and Tivoli models, but none with shortwave. I found prices about the same as Amazon.com, with the notable exception of a stunning Grundig S350DL NPR special limited edition well below Amazon’s price and with stereo headphones thrown in to boot.

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Receiving SSB on a radio without a BFO

Single sideband transmission is a way to transmit radio signals more efficiently. It’s used by amateur radio operators and commercial services. Most of the crop of moderately-priced shortwave receivers can’t receive SSB transmissions, making them sound like Donald Duck. More expensive receivers have a feature known as a beat frequency oscillator (BFO) to allow SSB to be heard normally.

All that’s needed to make it work is another carrier wave signal from another source. I happen to have an RF signal generator that I built from a kit in the 1960’s. Remarkably, it still works and all I have to do is tune next to the SSB transmission frequency I want to receive, placing the radio near the generator, and voilà, SSB reception. Tuning is rather tricky but possible. Maybe I can modify the unit to add a fine tuning control.

The generator is also useful in locating a very weak station on a radio with a rough analog tuning dial. I tune the station with a digital radio, tune the signal generator to be heard on the same frequency, and then tune the clear strong signal generator signal on the analog radio. Sometimes, it’s the only way to see if a station can be heard on one of these analog radios.

An alternative is a dedicated external BFO running near the IF frequency of the radio, 455 KHz (where I should have tuned the signal generator when I tried it). TenTec makes a kit for $11 and I have one on order. I should be able to put it in a small case and carry it around in my radio bag. I built kits when I was a teenager, even a 4-band tube type shortwave receiver (a Lafayette KT-340). This should be a piece of cake.

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One better: Tecsun R-912 radio

One of the top-rated budget ultralight shortwave radios is the Kaito WRX911 (also known as the Tecsun R-911). I have the Kaito-labeled version and it’s a respectable little radio. Add one to 911 and you get 912, inviting an obvious comparison to the Tecsun R-912 model that waltzed in today. My new radio was the Chinese version (there is also an English version).

Plus1

I was immediately struck by the similarity. Both cases are the same size and shape; the back could have been made by the same mold. Both have an identical 19” whip antenna and identical controls on the sides (volume, tuning, on-off) and jacks, 3v DC and earphone. Indeed, the only visible differences are the presence of extra button and two lights in the upper left corner of the Tecsun. The 911 switches all bands, including FM using the single band switch, while the 912 switches between FM and AM using the button, and notes which one is selected with the light (FM is the red light on the left).

There are two less-obvious differences that leads to the “one better” in this article’s title. First the second LED indicator upper right means something different on the two radios. On both radios the top light is a tuning/signal strength indicator. On the 911 the lower light just means “on” but on the 912 it indicates “stereo” for FM. Stereo is activated and the stereo light only comes on when headphones are plugged in. On my 912, the tuning indicator is on solid for the whole FM band and only shows signal strength on AM (on the 911 the tuning indicator works on all bands).

The second “one better” is in the number of bands: the 911 has 11 and the 912 has 12 (cool how that works out with the model number). The additional band is 3.55 – 4.0 MHz.

As far as performance goes, I couldn’t really tell any difference. Some folks say the FM is better on the R-912. Given how weak signals fade in and out, a real A/B comparison is difficult. Both radios drift some (wander off frequency) further complicating comparisons receiving weak signals.

These are respectable radios and you should be able to pull in a number of stations. If you don’t need stereo, however, I’d pick something like the Tecsun DR-920 with digital readout available for about the same price.

Looking for the Tecsun R-912 schematic diagram? Here it is.

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What’s the best shortwave radio under $50?

For what is being talked about as a dying hobby, shortwave radio is certainly blessed with a wealth of equipment to choose from. Here I’m going to talk about shortwave radios that can be purchased new on eBay, or Amazon or other online resellers. They may be out of production now, but are available. $50 includes shipping to the US.

Right up front, I’m going to say that the best radio is the Tecsun PL-380. 1 I make this conclusion based my on my experience, product reviews, and even YouTube videos of the radio in action. It’s available now from sellers on eBay (Oct. 10, 2014) for $48 with free shipping. I also base my conclusion on a lot of other radios under $50 that I have used.

image

“Best” makes little sense without context. I’m going to assume that someone is looking to get into shortwave listening or that they are a casual listener looking to upgrade an old radio. I want to talk about features that make a radio fun to use and not frustrating, features that make it more likely that the radio won’t end up in a closet or a yard sale. If you want more details on the radios discussed, follow the hyperlinks.

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The best shortwave receiver under $25?

My nomination for the best low-cost shortwave set is the Tecsun DR-920. It’s available from eBay sellers for around $17 and comes in gray and silver.

image

Right out of the box I noticed that the battery compartment door fit a little better than most of the low-priced radios I buy. The buttons and knobs are solid. The wrist strap is big enough. All in all, it seems well built and made a positive impression even before I turned it on.

After I turned it on, I was not disappointed. The tuning knob allowed precise tuning, with the frequency readout showing the exact setting. The display is to 5 KHz  on shortwave and 100 KHz on FM. The dial light wasn’t as bright as the photo, but it was adequate. I liked the fact that the dial light came on automatically while I tuned the radio (the light can also be turned on manually).

Reception was really outstanding for a radio of this class on all bands. I picked up CHU Canada on 7.850 MHz clearly (I’m in South Carolina) and reception wasn’t all that much better on my Grundig G4000A. I didn’t spend much time on AM, but I noticed that it picked up more stations that other small portables I have. FM performance was solid.

There are 10 shortwave bands (MHz):

  • 3.90 – 4.00
  • 4.75 – 5.06
  • 5.95 – 6.20
  • 7.10 – 7.30
  • 9.50 – 9.90
  • 11.65 – 12.05
  • 13.60 – 13.80
  • 15.10 – 15.60
  • 17.55 – 17.90
  • 21.45 – 21.85

The radio has one quirk. Pressing the power switch turns on the radio with the sleep timer activated, meaning it will turn off after the sleep setting expires. Maybe that is a good thing to save batteries. To turn the radio just plain on, you have to hold the power button down a couple of seconds.

Because this is a single-conversion receiver, it is prone to images — strong signals appearing on the dial on multiples of 455 kHz from the original signal. This can be confusing to hear a station on a frequency where it is not listed, nor actually broadcasting.

There is a lock button that keeps the radio from coming on accidentally, although the firm action of the power button makes accidental turn on unlikely. The radio operates on two AA batteries or an optional 3V DC adapter.

Things it lacks include: a signal strength indicator and FM stereo. The stereo version is sold by Eton as the G1100 for a much higher price tag. [The Et0n version of this radio is now selling on eBay right now for $12.99 including shipping.]

I have a lot of shortwave radios to choose from. I think this one is going traveling with me.

However, for $26 (if you’re lucky) you could get a Degen DE15 on eBay and it’s a better pick for its continuous digital tuning and stereo FM.

Update:

There is one more radio that’s come to my attention in the under $25 category: the Kchibo KK-D202. I’ve written a separate review of it. This radio has the disadvantage of all of the controls labeled in Chinese, and it’s AM performance is sucky. FM and Shortwave are, however, quite good, the radio is truly shirt-pocket size, it has a spiffy brushed aluminum face, a clock and station memories.

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Degen DE15 Vs. Grundig M400

Two identically sized mini radios go head to head

I was struck by the fact that two radios in my budget shortwave collection are so very similar in size, and I thought a comparison was in order.

Both radios cover AM, FM and Shortwave bands, have internal speakers and clocks with alarm. Both come with a carrying case, integrated antenna and ear buds. Both fit in a shirt pocket.

Degen DE 15

What impressed me right off the bat was the bright, and I mean bright, green display. You can see this thing! The DE 15 is a digital radio, meaning that the tuning is digital – no tuning dial. In addition to up/down tuning buttons, you can also scan for a signal and set up memory pre-sets. Volume is set digitally too.

Degen DE15

The radio includes 3 AAA rechargeable batteries, AC charger and plush draw-string carry bag. The charger system uses an included USB cable so that you can charge from your computer. The USB connector on the radio is the common mini-USB socket found on many devices: cameras, mobile phones, Bluetooth headsets and radios.

The clock was relatively straightforward to set. It supports a 12/24 hour mode. The clock displays when the radio is off.

Band selection is accomplished with a 4-position switch on the left side; however, the shortwave bands are selected by repeatedly pressing a button.

The operation manual is somewhat odd in its language, for example:

While tuning the stations, you had better get very close to the window or stand on the outdoor field in order to avoid the interrupt and gain the best reception.

The manual is careful to note that if power is interrupted, everything goes to factory defaults and the clock is reset. I was able, however, to quickly change batteries and retain the clock setting if I hurried.

There is an FML band, which corresponds to the VHF television channels; however, since VHF isn’t broadcast in the US any more, this is useless here.

One nice feature that both radios have is a slide lock switch that prevents the button controls from operating. If you have opened your luggage only to find the radio on and the batteries almost dead, you will appreciate this feature.

The radio has 245 memory locations for favorite stations, although there is no way to label them. There are separate memories allocated for each band, meaning that the 20 allocated to the FML band are wasted. It has an Auto Tuning Storage that I hadn’t seen before. It works like most TV sets, to scan the band and set up the stations you get. Here each band can be scanned and the strong stations automatically stored. I don’t know how useful this would be on shortwave, but it certainly makes sense for FM, with 100 station memories available. It worked OK, memorizing only two FM stations that were too weak to be useful. These can be easily deleted.

Both with the internal speaker and headphones, I found the the audio to be crisp but decidedly lacking at low frequencies.

Grundig M400

IMG_1259What impressed me right off the bat was the rubberized case. No slipping or sliding with this one. Mine is a deep cherry red in color (also available in black).

Unlike the Degen, the M400 is an analog receiver with a digital readout. There is a tuning knob on the right side. The tuning knob was easy to advance quickly and to tune precisely. However, the radio tuning would change by as much as 10KHz if I put my hand under the LCD display (so don’t do that).

There does not seem to be any dial light, so the radio would be difficult to operate in the dark, except that since tuning and volume are easy to find knobs on the side, I guess the radio could be operated blind.

The M400 shortwave coverage is in two bands: 5.90 – 10 MHz and 11.65 – 18 MHz. In actual practice, I could  tune a little beyond these published ranges (see following chart).

Both with the internal speaker and headphones, I found the the audio to be have less high-frequency response and more emphasis at low frequencies. Stereo reception seemed to give a more expansive impression than with the Degen. The volume control is easy to accidentally change and this is proving to be an issue.

Head to head

 Degen DE15Eton/Grundig M400
FM StereoYes, with earphonesYes, with earphones
Backlit displayYesNo
Frequency Coverage (MHz)MW .52 – 1.71
FM 87.00 – 108.00
FML 64.00 – 87.00
SW: 2.30 – 23.00

SW tuning is continuous, but there are 7 frequencies preselected when you press the band button repeatedly. They are:

6.00 MHz
7.30 MHz
9.50 MHz
11.70 MHz
13.50 MHz
15.20 MHz
18.20 MHz

AM .52 – 1.71
FM 87.00 – 108.00
SW 5.90 – 10.00
SW 11.65 – 18.00The previous frequencies are the published ones. In actual operation I could tune:

AM .505 – 1.768
FM 85.7 – 108.8
SW 5.745 – 10.57
SW 11.48– 18.59

Lock switchYesYes
Weight with batteries4.3 oz.3.9 oz..
Battery level indicatorYesNo
Signal strength indicatorYesNo
Battery3 AAA (rechargeable included)2 AAA
Power optionsUSB cable and AC adapter (included). Radio recharges batteries.4.5 – 5v DC (adapter not included)
Memories245n/a
Sleep timerYesNo
TuningDigitalAnalog
Tuning indicatorDigitalDigital
Clock DisplayHH:MM:SSHH:MM
Clock when radio is onYesNo
AccessoriesStereo ear buds, AC adapter, USB charging cable, carrying drawstring bag, 3 AAA Ni-MH rechargeable batteries, Operation ManualEar buds, carrying case with belt loop, stereo earphones, Operation Manual

Performance

I compared the two radios tuning WWV at 10 MHz and 15 MHz in the daytime both using the whip antenna. The Degen pulled in both reasonably well, but the Grundig did not receive the 10 MHz signal at all and was weaker on 15 MHz. There was one troubling issue with the Grundig. I head a faint signal from a local broadcast station over the entire tuning range of the two shortwave bands.

On FM the Degen was clearly superior in pulling in stations clearly that the Grundig missed entirely. AM on the Grundig was essentially dead, picking up only weakly the very strongest local stations. I’ve had better results with a crystal set. I was about to call Eton customer service when it started working for some reason. Go figure.

This practical exercise exposed one other shortcoming of the Degen. It takes a good bit longer to tune the radio. For shortwave, you repeatedly have to press the SW button to get close to the desired frequency, then push +/- buttons to go the rest of the way. On shortwave, it steps at 5KHz which can take a lot of button pushing to go very far. Memory presets help.

Conclusions

Both radios work well. The Grundig is a delight to hold with smooth and solid controls and rubberized non-slip case. Music sounds better on the Grundig. The  One concern with the Grundig is limited shortwave band coverage, for example the tropical band isn’t covered.

The extremely easy to read display, rock-stable tuning and continuous frequency coverage make the Degen stand out. The Degen is more expensive, but I found one on eBay for the same price as the Grundig.

So which is my pick? To listen to music on FM with headphones, I’d pick the Grundig. While I like analog tuning, the drift and relatively low sensitivity make the Degen a clear winner for anything else.

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