Monthly Archives: September 2015

National RF 75-NS-3 receiver kit

NationalRF-75-NS_2

National RF, of California, has introduced a new “semi-kit” receiver: the RF 75-NS-3. Here’s an excerpt from the product description page of the National RF website:

National RF’s 75-NS-3 receiver is a complete super-hetrodyne mini high frequency receiver, designed specifically for the short-wave listener, electronics enthusiast or radio amateur, who wants to use their hands and build a radio. The receiver is offered as a semi-kit in which the electronic assembly is loaded and functionally tested at the National RF facility. The customer must then go to the grocery store (yes…the grocery store!), procure a can of [Spam] lunch meat, eat it or give it to the dog, and then proceed to drill and paint the can, in order for it to become the receiver’s enclosure! […] Detailed drilling instructions and final assembly instructions are provided as part of the kit. All other parts required for completion of the receiver are provided as well. Recognizing that the finished assembly looked somewhat like the fabled Collins receiver of the ‘60s, the 75S-3, (particularly when the can is painted a light gray) National RF engineers dubbed it (with tongue firmly planted in cheek, of course) the 75-NS-3! Although we have had fun packaging this receiver in a lunch meat can, it is nothing to turn your nose at! Its performance and portability will surprise you, and it is an ideal radio to bring with you on any trip!

75-NS_3

The receiver architecture is that of a single conversion super-hetrodyne receiver, that is capable of receiving AM, SSB, or CW. The receiver incorporates a dual gate FET as an RF amplifier with manual peaking and gain controls. A ceramic filter is used in the IF section with a front panel switch that controls a broad or narrow IF response. Other front panel controls include audio drive, BFO setting, and a band switch for the HF bands. The 75-NS-3 has internal receive frequency coils that are switched at the front and rear panels. The frequency range of the receiver, over three band set positions, is 3.5 through 12 MHz. This allows reception of several international short-wave bands, the 80, 60, 40, and 30 meter amateur radio bands, and of course, WWV time and frequency standard stations at 5 and 10 MHz.

For those who simply want a lower cost receiver to monitor the shortwave frequencies, National RF offers two variants of the original receiver: the 75-NS-1 and the 75-NS-2. Both are based on the design and circuit of the 75-NS-3, but do not have the band switching and frequency range of the 75-NS-3 receiver. The 75-NS-1 covers between 3 and 6 MHz, including the 80 and 60 meter amateur band. The 75-NS-2 covers between 6 and 12 MHz, including the 40 and 30 meter amateur bands. Both units have the fixed ceramic resonator band width set for about 6 KHz. And, of course, they are both designed to fit in the tasty potted meat can!! All other specifications presented apply to both of these models as well.

Pricing of the 75-NS-x versions:

  • Type 75-NS-1 Mini HF Receiver Semi-kit (covers 3 to 6 MHz) $189.95
  • Type 75-NS-2 Mini HF Receiver Semi-kit (6 to 12 MHz) $189.95
  • Type 75-NS-3 Mini HF Receiver Semi-kit (band switched from 3.5 through 12 MHz in three switched positions) $269.95
  • Shipping and Handling to within the US $10.00 each

Click here to view on the National RF website.

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The Avion AV-DR -1401 DRM receiver to ship in October

DRM-Avion

Many thanks to several SWLing Post readers who shared this RadioWorld article about the new Avion AV-DR -1401 portable DRM receiver. According to RadioWorld, the AV-1401 will be sold through Amazon India as of October 2015 for approximately $175 US.

Click here to read the full article.

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Jeff’s bedside radio search ends with the Sangean CL-100

Sangean-CL-100

My pal, Jeff McMahon, over at the Herculodge writes:

A week ago, my Sangean WR-2 was fried when the electric company surged my house. I replaced it with the Grundig S350DL but it drifted too much.

I then used my superior Crane-SW radio (same size as the big Grundig) and guess what? It died! Those cheap radios today seem to die after 5 years or so.

So I looked through the myriad of unused radios in my cabinet and unearthed a Sangean CL-100 purchased in 2011. For whatever reason, it no longer works with batteries (old double As were left in there and leaked a tiny bit but compartment looked clean enough), so I plugged it in and it works.

FM is better than my Sangean WR-2. I think it has a DSP chip.
AM is better with low background noise, amazing for a radio this small.

Speaker is not as good as the WR-2, but it’s clear and okay since I listen mostly through earbuds.

Tiny footprint on my bedside table, which I like.

The menu system is easy enough to use though I wonder if down the road I’ll encounter bugs.

I bought this for about $45 and now it’s about $12 more.

It really suits my needs.

[A] man needs a strong performing bedside radio. That’s the backbone of a collection.

Indeed it is, Jeff!

I see why you like the CL-100. For a bedside radio, the flat/horizontal form factor also makes it less susceptible to being knocked over when you reach for it in the dark.

As for battery operation, you may try removing some of the corrosion on the battery contacts with a file or something mildly abrasive. I’d also hit it with a little Deoxit. (Though knowing Jeff, he’s probably already on this.)

Lead_Free_Solder_05mmHaving your Sangean WR-2 fried by the power company is bad enough, but then finding out your C.Crane CCradio-SW isn’t working just adds insult to injury.

I should note that, in general, I think C.Crane products are built as well as most others on the market.

I often wonder if premature product failures have less to do with poor quality control and more to do with the lead-free solder electronics manufacturers are forced to use these days.

Many moons ago, a friend sent me this article which outlines concerns about the use of lead-free solder in the military and aerospace industries. It’s worth a read and certainly points out inherent flaws. I often wonder if nearly all of our modern consumer electronics are prone to fail within a decade; you know, planned obsolescence at its worst. Perhaps I’m overreacting.

When I build kits or repair electronics, I only use traditional lead-based solder. Not only is it easier to use, but I feel it will last longer.

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Special VOA Radiogram broadcast for European Researchers’ Night

Fullscreen capture 9232015 13931 PM(Source: VOA Radiogram via Richard Langley)

VOA Radiogram will participate in European Researchers’ Night 2015, specifically to the Notte europea dei ricercatori at Frascati, near Rome. There will be a special broadcast of VOA Radiogram Friday, 25 September, at 1830-1900 UTC, on 17880 kHz, via the Edward R. Murrow Transmitting Station in North Carolina.

This broadcast is in addition to regular VOA Radiogram schedule:

(days/times UTC):
Sat 0930-1000 5745 kHz
Sat 1600-1630 17870 kHz
Sun 0230-0300 5745 kHz
Sun 1930-2000 15670 kHz
All via North Carolina

More information:

http://voaradiogram.net

http://ec.europa.eu/research/researchersnight

http://www.frascatiscienza.it/pagine/notte-europea-dei-ricercatori-2015

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