Category Archives: FM

Memories and transistor radios

Magnovox 1R 1203 I’ve always had an affinity for pocket transistor radios.

The Realistic Model 23-464.

My first one was an AM-only model: a Realistic Model 23-464. It was about the only new pocket radio I could afford–and purchase locally–when I was a kid.

It was surprisingly sensitive on the AM broadcast band, but the dial was a far cry from accurate. At some point, I either gave this radio to someone or lost it. Last year, I happened upon one on eBay and purchased it for $9 shipped. Its plastic body shows signs of wear, but it works and reminds me of my childhood.

My grandpa’s Magnovox 1R 1203

Another pocket AM/FM radio that brings back a flood of memories is the Magnovox 1R 1203. It belonged to my dear grandpa, who also shared and conveyed a love of radio. When I was a kid, we would sit around on his front porch on hot summer days and listen to local AM stations on this little radio, cicadas whirring in the background.

I still have his Magnavox–it sits here in my radio room and brings back memories every time I look at or listen to it.

Am I a nostalgic fellow? You bet!

Anyone else have memories associated with pocket radios? Please feel free to comment and share!

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The “Hidden Den” of Pirate Radio

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Many thanks to SWLing Post contributor, Martin Kraft, who writes:

Where’s the hidden den of pirate radio? The Caribbean? The South China Sea? Nope, according to RadioWorld, it’s the New York City metro area:
http://www.radioworld.com/article/nybsa-76-pirates-stations-in-new-york-northern-nj/279213

NYSBA: 76 Pirate Stations in New York, Northern N.J.

A number of pirate stations are operating throughout New York City and Northern New Jersey, according to a recent engineering survey that was recently unveiled by the New York State Broadcasters Association.

According to the survey, 76 stations are currently operating without an FCC license in four primary locations. There are 19 unauthorized stations in the Bronx, N.Y.; 29 in Brooklyn, N.Y.; 13 in Newark, N.J.; and 15 in Paterson, N.J. Brooklyn saw a 58% increase in the number of pirate stations compared to a similar survey conducted in 2015.

The survey does observe that it has likely underestimated the number of pirate stations in the area, and that the total number could be more than 100.

“Like our previous studies, the new survey provides compelling evidence that the FCC needs to address this problem,” said David Donovan, president of the NYSBA. “Last summer, the entire New York Congressional delegation asked the FCC to fix the problem. While the FCC has published an Enforcement Advisory, it needs to devote the manpower and resources to increase its enforcement efforts. Moreover, Congressional action will be important to assist the FCC in these efforts.”

The potential harms associated with pirate stations include: interference to Broadcast Emergency Alert Services; interference to FAA frequencies; and failure to comply with RF radiation rules of licensed broadcast stations.

The survey was conducted by engineering firm Meintel, Sgrignoli and Wallace. The full study can be found here.

Thank you, Martin!

When I visit my buddy David Goren in Brooklyn, I’m simply amazed at the diversity of the pirate radio scene on the FM band. When David isn’t surfing the shortwaves, he’s logging local pirate radio stations. Check out his Facebook page: Flatbush Pirate Decoder. David most recently presented a program on the NYC pirate scene at the 11th HOPE conference–you can download a recording of the presentation here.

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Battery Endurance Contest Results: Sangean DT-160CL vs Sony SRF-39FP

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On August 4, 2016, the same day I received my new Sangean DT-160CL, I popped a fresh set of CVS Max Alkaline batteries into the DT-160CL as well as into my trusted Sony SRF-39FP. The mission? To see which radio could perform longest on a set of batteries.

I set my stopwatch as I turned on both radios, tuned to the same frequency, set the volume to the same levels…and waited.

And waited. And waited. And as I waited, I posted updates.

But at last, the waiting is at an end: here are the contest’s final results.

Sangean DT-160CL: Impressive Performance

On August 9, I reported that the Sangean DT-160CL finally threw in the towel, logging an impressive 116 hours 30 minutes of operating time–!

Without a doubt, this is one of the longest run times I’ve ever experienced from an AM/FM radio with digital display.

Interestingly, the day after the DT-160CL shut down, I turned it back on, and it operated for an additional 45 minutes or so, obviously absorbing a little more voltage from rested cells. During that 45 minutes period of time, the audio and overall performance was respectable. No doubt the DT-160 shuts down before audio is terribly compromised.

Sony SRF-39FP: The Endurance King!

Amazingly, the Sony SRF-39FP kept running well beyond 116 hours. Well beyond…

By Wednesday morning–one full week from the time I began the endurance contest–the Sony SRF-39FP finally began showing signs of low-voltage: the audio had a small amount of splatter and sensitivity began to be compromised.

Unlike the Sangean DT-160CL, which clearly has a cut-off voltage, the SRF-39FP kept milking the battery for its last vestiges of power.

I decided that I would call a “time of death” for this AA battery when the Sony struggled to receive local AM stations, as well as transmission from my in-house SStran AM transmitter.

This happened approximately 163 hours and 54 minutes into its marathon run.

This stopwatch app tracked the full endurance test. I pressed “stop” when the Sony SRF-39FP finally gave up.

Wow, wow, wow. I simply had no idea any portable could operate almost one full week on one AA cell–!

In truth, I’m sort of relieved the ’39FP finally gave up the ghost. I was beginning to think the thing was powered by some supernatural force…

When I started this test, I thought the Sony SRF-39FP was rated for about 40-80 hours of run time on a single battery. I couldn’t remember where I got that number until I recently re-read this article from The New Yorker, which highlighted the 39FP’s role in correctional facilities:

“The SRF-39FP is the gold standard among prison radios in part because it runs on a single AA battery, and offers forty hours of listening time…”

Wait, just forty hours? Perhaps from the cheapest AA battery made…

With an advanced chemistry cell like the Duracell Quantum or Energizer Advanced Lithium series, you’ll clearly get three to four times that performance.

DX mode

And here’s the thing: I’m convinced I could’ve gotten much more time out of the SRF-39FP.

Like similar Sony portables, the SRF-39FP has a “DX/Local” switch. When set to DX, the receiver is made to deliver maximum performance.

If you’re listening to a local station, however, “Local” mode is a better choice. You’ll still be able to receive your target station, yet draw much less from the battery.

I left the Sony SRF-39FP in “DX” mode for the entire battery endurance test. Had it been in “Local” mode, I believe I’d be reporting an even longer run time. How much longer, I don’t know, but you can bet that my curiosity will soon get the best of me…I plan to do a separate endurance test to find out.

Clear choices for battery longevity

Sangean-DT160CL and Sony SRF-39FP No doubt, our little test has proven that radios marketed to the prison system do offer excellent battery performance.

Now I’m very curious whether the standard Sangean DT-160 will offer the same battery performance as its clear-cased counterpart, the DT-160CL. The only difference in the two appears to be that one offers a clock, while the other doesn’t. I wonder if that would have any significant difference on battery life.

Additionally, the Sony SRF-39FP has shown us that analog receivers can be much more efficient than their digital counterparts. We’ve known this a long time at Ears To Our World, and which is why almost all of the radios we supply to schools in remote, rural locations are analog.

Sadly, analog radios are getting much more difficult to find these days as DSP-based receivers have become more affordable to produce.

The Sangean DT-160 is available at Amazon.com and Universal Radio. The Sangean DT-160CL (the version tested) is available through Amazon.

Click here to search eBay for the Sony SRF-39FP.

Readers: Know of any other battery-miser radios? Please comment!

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Update 4: Sangean DT-160CL v Sony SRF-39FP

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If you’ve been following the Sangean DT-160CL versus Sony SRF-39FP battery endurance test, I have some news to report: one of our competitors has finally thrown in the towel…!

Yesterday, while I was on the road for about 1.5 hours, the Sangean DT-160CL at last gave up the contest.

Since I was traveling at the time, I can’t say with absolute certainty what o’clock the DT-160 cried uncle––but roughly, we’re looking at 116 hours, 30 minutes of run time, give or take 30 minutes.

Sangean claims the DT-160 series will operate for 100 hours with two AA batteries. That claim is obviously pretty conservative.

Though I used CVS Max Alkaline batteries (a generic version of Duracell’s Quantum batteries)–an improvement on the standard alkaline battery–I set the volume higher than I believe Sangean or Sony would have set it for testing purposes. This should have drained the batteries faster. The radios were also tuned to a variety of stations: weak AM, strong AM, weak FM and strong FM.

In short: I’m very impressed with the DT-160.

A 116 hour play time from two AA cells on a digitally-tuned receiver is, well, pretty incredible.

Now that the endurance test is over for the DT-160CL, I’ll replace the batteries with a fresh set of CVS Max Alkaline cells and start testing the AM/FM receiver performance.

…And how about the Sony SRF-39FP?

My iPhone’s stopwatch has been tracking progress since last Wednesday.

Even more amazingly, the Sony SRF-39FP is still going strong––!

I actually fell asleep last night listening to the SRF-39FP and woke up this morning with music still in my ears. What a champ!

So, how long has the Sony SRF-39FP now been operating on one AA battery?

At time of posting, this little Sony’s clocked one hundred thirty nine hours.

Though I’ve always known that the SRF-39FP was a true battery miser–one of the reasons it’s been a choice radio in the prison system–I had no idea it could operate this long on one battery.

Of course, I’ll continue tracking the Sony SRF-39FP.

How much longer will the SRF-39FP last? Stay tuned to find out!

Follow this review thread by bookmarking the following tag: Sangean DT-160CL v Sony SRF-39FP.

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Update 3: Sangean DT-160CL v Sony SRF-39FP

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My iPhone’s stopwatch has been tracking the endurance test.

It’s been one hundred nine hours since I started the Sangean DT-160CL versus Sony SRF-39FP battery endurance test and both radio are still hanging in there!

Not knowing which radio will check out first, I’ve been taking them with me everywhere and have been careful to keep their settings identical the whole time.

Last night, I even prepared my Zoom H2N digital recorder to monitor both radios simultaneously. Having passed 100 hours of operating on the same set of batteries, I was certain one would call it quits last night.

Not so.

There was one noticeable change this morning: the Sangean DT-160CL’s battery indicator now shows a depleted cell.

It’s still operating, though–no noticeable difference in volume and reception.

The end must certainly be near! Indeed, it’s hard to believe I started this endurance test last Wednesday!

I’m very interested to see which pocket radio will go first.

Field time

Yesterday, I spent the better part of the afternoon at Mt. Mitchell State Park. Of course, I brought the DT-160CL and SRF-39FP along.

Mt. Mitchell is the highest point east of the Mississippi river. It’s a great place to play radio.

At one point, I tuned both radios to WAIZ 630 kHz: a 1,000 watt AM station about 95 miles east of the park. It’s one of my benchmark daytime stations from Mt. Mitchell.

Though most DT-160 reviewers have given the receiver low marks for AM performance, I found that the DT-160CL did a better job locking onto WAIZ than the venerable SRF-39FP.

Perhaps this is due to the fact that both radios, at that point, were operating on low voltage? Or perhaps the CL version of the DT-160 series has better AGC characteristics and sensitivity?

I doubt the latter assumption, but once the endurance test is complete, I’ll put the 160CL through the paces.

Follow this review thread by bookmarking the following tag: Sangean DT-160CL v Sony SRF-39FP.

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Tom Servo reviews the Sangean DT-160

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Many thanks to SWLing Post contributor, Tom Servo, for sharing the following review of the Sangean DT-160. His review was originally posted on the radio discussions forum:

Got my Sangean DT-160 today. Thanks, Santa Claus!

Initial impressions are positive, both in the build quality and performance.

It’s a lot bigger than I thought it’d be, though.

I was picturing in my mind something closer to the SRF-M37 but it’s bigger than a pack of cigarettes — taller and wider.

Some of the performance issues others have noted, I’ve noticed as well. The FM reception is superb and outperforms the Insignia HD portable that’s my benchmark FM radio. It can hold its own with the Grundig G8 in that regard.

The sound quality is weird, though. It sounds “crunchy” or watery. Like everything is being played via a low bit rate mp3. Granted, most my local stations ARE playing low bit rate mp3s and sound terrible (which is why I don’t listen to local radio much anymore) but the few stations that aren’t still sound “weird”. Crispy. It could be the DSP or just some odd EQ’ing on Sangean’s part. It’s not a deal-breaker by any stretch but when side-by-side with a different radio the audio differences were stark. The Insignia sounds truly “flat” while the Sangean sounds treble boosted. And crispy. Did I mention that?

[At first] the wide-narrow setting [seemed to make little] difference on FM. The only station that narrow mode improved was while listening to WTGF out of Milton, FL. It’s a mono station and I’m on the fringe, and the narrow cleared up a bit of static. It makes a much more noticeable different on AM, though. Not as much as a well calibrated “wide/narrow” filter might but enough to help some talk radio stand out from the noise.

[I did eventually] figured out where the wide-narrow setting makes the most difference on FM. It’s when you have two signals on adjacent channels, the narrow really does help cut out adjacent channel splatter. Not that there’s much of a problem to begin with, but it is a little extra added oomph.

With the narrow activated, I was able to pull in 93.1 WGDQ and 94.3 WKZW from the Hattiesburg, MS market. Two stations I haven’t heard in probably a year or better, and both are first-adjacent to local 100 kW sticks that are less than 15 miles from me.

Selectivity even in wide mode is fine. Definitely better than the Insignia and on par with the Grundig. We have a crowded dial here on the Gulf coast and sometimes you need a selective radio to pull out all the stations side by side. Here’s an example of what is possible to hear on a decent night:

98.1 – WHWY – Fort Walton Beach
98.3 – WLVM – Mobile
98.5 – WYLD – New Orleans
98.7 – WYCT – Pensacola

I was surprised to hear WYLD coming in this afternoon. In fact, at first I thought it was an image of local 99.9 WMXC, because it was the same song/DJ. But the IDs were different. That’s a good pull and something neither the Grundig nor Insignia could pull off.

The dynamic bass boost is a horrible sounding gimmick, though. It makes everything sound muddy on my “real” headphones. I didn’t try the ones that came with it. I hate it that it lacks RDS, since so many Sangean radios have that and it makes DXing more interesting. The AM has a weird squelch like damping when it’s on an empty channel. If there’s a weak signal there (like my semi-local but hard to hear WABF out of Fairhope) it just sits there, perfectly quiet. It’s not until I used the Tecsun loop with it that reasonably clear audio came out of nowhere. I strongly suspect it’s “muting” weak signals on purpose on AM.

WWL is a moderate but noisy target here; the signal strength is usually good enough for even basic radios to pick it up… Not this Sangean. It took careful alignment before I heard anything. The slightest bit of movement and it went almost completely deaf again. Very odd.

It’s a shame that conditions for FM DX have been so poor on the coast this year, I think this would be a killer DX machine on FM. My friend in Florence has heard Mexico and Wyoming this year. I’ve barely made anything further west than New Orleans, which is pitiful.

Another plus is it drives my large Sennheiser headphones louder than any other “pocket” radio in my collection.

Thanks for sharing your review, Tom!

I sounds like the DT-160’s AGC or soft mute on the AM broadcast band is causing otherwise intelligible signals to drop out.

At time of posting, I’m still running the battery endurance test of the Sangean DT-160CL vs. Sony SRF-39FP, so I haven’t really given the DT-160CL (the correctional version of the DT-160) a proper receiver performance test. I will soon enough, though!

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Update 2: Sangean DT-160CL v Sony SRF-39FP

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It’s been eighty seven (!!!) hours since I started the Sangean DT-160CL versus Sony SRF-39FP endurance test and both radio are still going strong.

My iPhone stopwatch has been tracking the test.

I’ve tuned both radios to my SSTran AMT3000 AM transmitter which is currently re-broadcasting the UK 1940s Radio Station on 1570 kHz.

The Sangean DT-160CL still shows two of three segments on the battery indicator (see above).

The Sony SRF-39FP seems to have no indication of quitting anytime soon–it’s still sensitive and audio sounds great.

I believe the Sony SRF-39FP is rated for 80 hours of playtime, and I’m sure if I had turned it on and off numerous times during the test, it might have had an impact on battery performance. It’s still going strong, though.

I am using advanced alkaline (CVS Brand) batteries in both radios. These should give each radio better battery life than standard alkaline or rechargeables.

Regardless which radio wins this test: both have already proved themselves “Holy Grail” battery misers!

I’ll be monitoring the radios very closely today as we pass the 90 and 100 hour mark!

UPDATE: Shortly after making this post–at almost exactly 88 hours and 30 minutes into the test–the Sangean DT160CL’s battery indicator lost a battery indicator segment. It’s now only showing one of three battery segments. Could the end be near for our DT-160CL? Stay tuned!

Follow this review thread by bookmarking the following tag: Sangean DT-160CL v Sony SRF-39FP.

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