Mesh cages to shield noisy power supplies

Many thanks to SWLing Post contributor, TomL, who writes:

Hi Thomas,

Stumbled onto this article while on the RTL-SDR website. Talks about shielding noisy power supplies inside a homemade wire mesh cage. It might be interesting as a weekend project. I wonder if a noisy laptop could be put inside one of these things, too?

https://macradiodiysdrsystem.home.blog/2019/02/17/the-all-new-remote-rig-part-1-1-testing-the-hf-shield/

Thanks for the tip, Tom! As this author states, it looks like it’s well worth the time and the wear and tear on your fingers to build one of this mesh cages.

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TC notes differences between Kenwood TH-D74 and TH-F6A on MW/SW

Many thanks to SWLing Post contributor, TC, who shares the following response to Ivan’s post about the Kenwood TH-D74 on mediumwave:

A couple of years ago, I published a side-by-side comparison of the TH-F6A and the TH-D74 on YouTube comparing reception of a local AM broadcast station. The F6A was far more sensitive on the AM broadcast band than the TH-D74.

You can see the video here:

Click here to view on YouTube.

I didn’t take the internal orientation of the bars into account, but the D74 is less sensitive in pretty much any orientation compared to the older F6A.

I contacted Kenwood about the difference, and they stated something to the effect of while the TH-D74 does receive MW, it wasn’t necessarily designed for it, and thus the reception there suffers compared to the F6A.

However, the tradeoff here seems to be better shortwave reception in the TH-D74 compared to the F6A. Hook the D74 up to a large wire antenna and you can easily pull in stuff on the shortwave broadcast and ham bands, and the IF filters help quite a bit as well.

Thanks for sharing, TC! I own a few wideband handheld transceivers so I keep a short SMA “pigtail” in my EDC pack that I can use to enhance HF performance. I simply clip a 15′ wire onto the pigtail’s  exposed conductor to enhance HF performance. Also, as Ivan points out, inductively pairing any of these tiny radios with a mag loop antenna will also augment performance on mediumwave.

Thanks again for sharing!

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Radio Deal: Eton Executive Traveler $49.93

Many thanks to SWLing Post contributor, Christian, who writes:

Just a note that the Eton Executive Traveller’s price has dropped to $49.93 shipped on Amazon.com. It’s the lowest price I’ve seen for this radio in a few months. Thought your readers might be interested. As I’ve said before, I think it’s a great little radio. This is Amazon, so the price can change without notice.

Thanks for the tip, Christian!

Click here to view on Amazon (affiliate link that supports the SWLing Post).

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Photos from the 2019 Charlotte Hamfest

This RS HF receiver was pristine. If I had the budget and the shack space, it would have gone back with me. See more photos in our gallery below.

Yesterday morning around 5:30 AM I started my nearly three hour pilgrimage to the 2019 Charlotte (North Carolina) Hamfest. The Charlotte Hamfest is one of the larger regional hamfests in the area–due to its central location, it attracts people from all of the surrounding states.

The Charlotte Hamfest typically falls on the heels of (or the same weekend as) the Winter SWL Fest in Pennsylvania so I usually don’t even put the dates in my calendar. Indeed, the last time I attended the Charlotte Hamfest was about twenty years ago! It was at a different location and, back then, was also very much a computer show. Today it’s almost purely radio.

Following Vlado to the hamfest site on a very foggy, rainy Saturday morning.

The Charlotte Hamfest is a Friday/Saturday event held at the Cabarrus Arena & Events Center in Concord, NC. The center is a superb hamfest venue: it’s well lit, clean, spacious and can easily house all of the vendors indoors–a huge bonus as weather was less than desirable.

My buddy, Vlado (N3CZ) reserved two vendor tables and packed it with gear to sell–I also brought along a handful of items.

I was very impressed with the turnout–indeed, it was one of the busiest regional hamfests I’ve attended in ages. I sold a couple of items and Vlado sold a lot (he also purchased a lot, but that’s another story!).

I believe I’ll start putting the Charlotte hamfest in my calendar–even though timing isn’t always convenient for me, I think it’s well worth the trip!

Kudos to the Mecklenburg Amateur Radio Society for putting on such a great show!

Photos

I’ve embedded over 140 photos of the Charlotte Hamfest below–click each one to enlarge. Being a lover of vintage radios, my photos feature a lot of boat anchors. Note that when possible, I try to include the price tags for each item.

Note: If you can’t view the embedded photos below in our email digest, click here to view them on the web.

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Guest Post: 2019 Henry’s Island DXpedition catches

Many thanks to SWLing Post contributor, Sandipan Basu Mallick (VU3JXD), for sharing the following guest post:


2019 Henry’s Island DXpedition with Perseus – Logs by Debanjan Chakraborty (VU3DCH)

This year’s DXpedition to Henry’s Island on 10th -13th Feb 2019 witnessed some of the finest receivers available in the country. Among them, there were 3 Perseus SDR which made it to this year’s expedition. Powered with Active Mini Whip Antennas, there have been terabytes of recordings of airwaves.

Perseus array

Expedition member Debanjan Chakraborty (VU3DCH) shared some of his loggings with the Perseus during the DXpedition :

HLAZ Korea FEBC on 1566 KHz

Click here to view on YouTube.

Voice of Greece on 9420 KHz

Click here to view on YouTube.

Radio Exterior De Espana on 12030 KHz

Click here to view on YouTube.

NBC Bougainville on 3325 KHz

Click here to view on YouTube.

Until now we all knew about the pirate stations in Europe and America. However, DXpedition to Bay of Bay of Bengal had some surprise in store for us. Yes, it’s the pirate stations of Bay of Bengal flocking the Medium Wave which were the prized catch. Below are the Bengali Medium Wave Pirate Stations logs

Bengali Medium Wave Pirate Sagardeep No 1, 1272 KHz

Click here to view on YouTube.

Unknown Bengali Medium Wave Pirate 1127 KHz

Click here to view on YouTube.

Unknown Bengali Medium Wave Pirate on 1251 KHz

Click here to view on YouTube.

Unknown Bengali Medium Wave Pirate 1388 KHz

Click here to view on YouTube.

More About Dxer Debanjan Chakraborty (VU3DCH): http://radiowaveshunter.blogspot.in/

Debanjan Chakraborty (VU3DCH) Scanning the Airwaves

Debanjan Chakraborty, is a self taught DXer from the city of Kolkata, West Bengal, India. In mid 90’s when he came across an article about radio listening and became fascinated by the hobby to scan the airwave for signals from far way land. His first QSL was from Radio Netherlands in 1996 and in over 2 decades now, adding up to a few thousand QSLs in his collection. It was only in 2009 he started his blog RadioWavesHunter http://radiowaveshunter.blogspot.in/ to put up his loggings and QSL collections. Interestingly his blog site has garnered over 12K+ visitors from across the globe. He has also, got some of vintage radios scanning the airwaves. Sony ICF 5900 (1975), Panasonic FR 2200 (1977), Yaesu – Musen FRG-7 (1976 -1980), Kenwood R-1000 (1979) and Sony ICF 2010 (1985) are few from his collection.

Follow blog (http://radiowaveshunter.blogspot.in/) for more about his loggings and QSL archive.


Thank you for sharing your DXpedition videos! Those are some excellent catches! We look forward to your future reports.

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Ivan checks out the Kenwood TH-D74’s mediumwave performance

Many thanks to SWLing Post contributor, Ivan (NO2CW), who writes:

One category of receivers not much talked about are the wideband handhelds. I first owned one of those in 1992 when I paid a ton of money for an AOR-1000. Not only did it cost me a lot but I also ordered it from the UK so it was not subject to the “cellular blocked” rule. Don’t ask me why, it never made any difference in the end.

As a busy shortwave listener at the time I was eager to check out reception as the radio also featured Shorwave coverage and even a BFO (Beat Frequency Oscillator) knob! To sum it up it was a great receiver above 30 mHz but Shortwave and Mediumwave was barely there, with a 15 kHz wide filter and low sensitivity.

Well today I have in my hands a Kenwood TH-D74A – a top of the line handheld triband amateur radio transceiver with Medium Wave and Short Wave coverage. The radio is expensive due to the presence of GPS, D Star and APRS, but those are a features for the radio amateur. What about performance on the low frequencies?

Here is my video of the test which revealed surprising results:

Click here to view on YouTube.

So next time you consider purchasing a new receiver,as you dive into the choice of portables, SDRs, tabletops and classics from eBay you may consider adding this category as well – handhelds with wide band coverage.

Thank you, Ivan!  You’ve inspired me to check out mediumwave performance on a few wideband handy talkies I own: the Yaesu VX-3R, Yaesu FT2DR and the Kenwood TH-F6A. To my knowledge, all three have internal ferrite bars (tiny ones) but I’ve never actually compared their performance with each other. That could be a lot of fun. I also own an AN200 MW loop antenna so this could be an excellent test to see how it pairs with each radio.  I’m especially curious about the wee VX-3R!

Thanks again, Ivan. We always enjoy your videos and posts.

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Advice on preserving 1940s era homemade records

At the Winter SWL Fest last week, my friend, Andrew Yoder (author of the Pirate Radio Annual) told me about a recent find: homemade records by amateur radio operator W3JJN.

Andrew wrote about these recordings on his blog:

[…]Before open-reel decks were wire recorders. Information was magnetized onto a fine reel of stainless steel wire. It was essentially the same concept as tape decks, whether open reel or cassette, only the tape system was a refinement (an oxide coating on a plastic tape), rather than trying to magnetize a wire.

[…]Before wire recorders were record recorders. These took an audio source and the needle cut a blank disc with grooves. From what I understand, these homemade discs weren’t meant to be played back too many times because the needles wore into the grooves more quickly than commercially manufactured records. I’m not sure what they were all made from, but I know that some were aluminum discs with a thin layer of plastic.

I always look for the homemade records because there weren’t too many options for audio sources back then. By the open-reel tape era, a lot of people were recording entire albums to tape, so they weren’t necessarily recording the radio. But, for example, in 1940, the options were basically either family greetings, someone singing or a band playing, or the radio. And chances are good that any recording you find is the only one in existence.

I found three of these on Saturday.

Here’s a photo of one.

They are amateur radio QSOs from W3JJN to a couple of other operators. W3JJN cataloged the discs by side . . . and this was number 477. So, at least 237 other records existed in his homemade record collection at one time. The sides that I have are dated in late 1945 and early 1946. To me, this is an astounding find because I’m not sure how many recordings exist of any amateur radio operations prior to 1950, not to mention that this is still very early in the post-war period.

I did some searching on W3JJN and he was William E. Belz, who lived at that time on 1509 Linden Avenue in Baltimore, Maryland. He was a TV repairman who was born in Duncansville, PA, and died in 1981 after a lengthy illness.

My big problem here is that these records are disintegrating. The plastic layer is cracking badly and separating from the aluminum discs. I guess what I really need is one of the laser turntables that can play back audio from broken discs and won’t damage the grooves. I don’t think I can risk playing any of these on a regular turntable, but I want to recover the audio quickly before the discs degrade further.

Click here to read the full article.

Post readers: Any advice on preserving these recordings? It sounds like using an actual needle to make a digital copy might be a little too destructive.  Are there alternatives?  Please comment if you have any experience or suggestions!

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