Category Archives: Boat Anchors

Dan spots the ultra rare Hammarlund SP-600 JX21A on eBay

Many thanks to SWLing Post contributor, Dan Robinson, who discovered a very rareHammarlund SP-600 JX21A on eBay. Dan writes:

Collectors of classic boatanchor gear know what has been probably the rarest of tube sets year after year, decade after decade. That set is the Hammarlund SP-600 JX21A.

While there have been numerous JX21s on eBay, there has not been, to my memory, a single JX21A appearing. This particular model was a version of the SP-600 that was produced in small quantities in the 1960’s, and according to one writeup was the only one with a product detector and switchable sidebands. According to Radiomuseum it was the last model in the SP-600 series, and was recognizable for its knobs which were different because the silkscreen information was printed directly on the front panel rather than on the edge of the knob skirts.

According to Les Locklear’s excellent history of SP-600 models, the JX21A was produced between 1969 and 1972.

Now, an ultra-rare SP-600 JX21A has appeared on eBay. Like other models in the series, this would likely require replacement of numerous capacitors and a thorough refurbishment. The seller in this case has started bidding at a very low level, but if history is any guide, a rare model like this one may indeed go for thousands of dollars when all is said and done at the end of the auction.

Click here to view the Hammarlund SP-600 JX21A on eBay.

Amazing!  Thank you for sharing, Dan! What a gorgeous set. Though the seller states it’s in need of restoration, I’m pretty sure this one will get snagged up at end of auction. I’m very curious where the final price will land.

Are there any SWLing Post readers who own an SP-600 model–or the JX21A?  Please comment!

South African Antique Wireless Association Valve QSO Party on May 6, 2018

(Source: Southgate ARC)

Antique Wireless Association Valve QSO Party

The AWA Valve QSO Party is a phone contest held over two sessions on Saturday 5 and Sunday 6 May 2018.

On Saturday afternoon the AM session will be on the air from 13:00 to 17:00 UTC and on Sunday the SSB session will run from 13:00 to 17:00 UTC.

Activity on both days takes place on 40 metres between 7 063 and 7 100 kHz and on 80 metres between 3 603 and 3650 kHz with your call sign a RS report, a consecutive serial number starting at 001 and the type of radio used, e.g. HT37 Tx as the exchange.

Log sheets must be submitted by 25 May by e-mail to andyzs6ady@vodamail.co.za or by mail to the Antique Wireless Association of Southern Africa, PO Box 12320, Benoryn, 1504.

Certificates will be awarded to the first three places in each category (AM/SSB). Please consult the 2018 SARL Contest Manual for all the information.

The South African Radio League

“The Shape of Water” features a benchmark Cold War receiver

Many thanks to SWLing Post contributor, Dan Hawkins, who writes:

The Academy Award for Best Picture of 2018 goes to Guillermo de Toro’s “The Shape of Water.

This celebrated shortwave radio appears several times in the move as a prop for the Cold War-era control room of Richard Strickland (played by Michael Shannon).

Oh what a celebrated shortwave radio indeed! How could it be a Cold War without this benchmark boat anchor?!? Thanks for this fantastic addition to to our growing archive of radios in film, Dan!

Post readers: Anyone recognize or–better yet–own this amazing machine? Please comment!

WWII Radio: Truman and the Scott Radio Labs RBO-2

Many thanks to SWLing Post contributor, Kim Elliott, who recently shared the photo above of President Harry S. Truman via @RealTimeWWII.

If I’m not mistaken, that is a Scott Radio Labs Model RBO-2.

I’m guessing that’s also the speaker mounted on the wall directly above the receiver.

Scott Radio Labs marine receivers were shielded to the point that they had very low local oscillator radiation. This design prevented detection of the ship via the enemy’s use of radio direction finding gear.

I have a commercial Scott Marine Radio Model SLRM–it is my favorite receiver and I use it daily.

Post readers: Anyone else have a Scott Radio Labs receiver in their shack? Please comment!

Seventy years ago, Thor Heyerdahl packed a National NC-173 and made history

The National NC-173

Many thanks to SWLing Post contributor, Kris Partridge (G8AUU), who sent the following feedback a few days ago. Sorry for missing the boat, Kris!

Kris writes:

Just under two weeks ago I was watching a Norwegian film on Polish TV (no, don’t ask) and knowing how the sight of old radio’s in films is of interest to you and your readers I was going to write but travel and work, Passendale100 commemorations in Belgium, got in the way. The radio in question was a National NC-173 receiver. And the film Kon-Tiki.

There is much written about the exploits of the voyage and the operators of LI2B. I give as an example from PA7MDJ http://pa7mdj.blogspot.co.uk/2016/10/the-kon-tiki-expedition-and-heroes-of.html?m=1 I leave it to PA7MDJ’s most excellent blog to tell more, he has some Nation Radio Company images from 1947 illustrating his piece and at the end there is a very extensive links listing.

But another reason for writing is that tomorrow, Monday, 07 August is the 70th anniversary of the end of the voyage as the raft landed on the reef. On the 67th anniversary the ARRL did an article on LI2B, why the 67th?

What happened on the 7th of August 1947, and in the 36 hours after, says much about the build quality of the National NC-173.

How many radios today would survive a dunking in seawater and after drying out still be working?

I’ve just been to my book shelves and after a small search found my copy of The Kon-Tiki Expedition published in 1950 given to me not too many years later.

You find LI2B in the book’s index twice. Once describing the operation of the radio ‘corner’ and a very QRP contact between the raft and Oslo Norway. 6 watts CW on 13990 kc. per second, the book being written in 1949 no kHz.

LI2B had been given permission to operate out of but adjacent to as well as in the 20 metre band. The second entry concerns what happen after the raft ends up on the reef and the radio shack and equipment got flooded.

They had been in contact before hitting the reef and there was a 36 hour window before the air search and rescue operations would begin. The drying out of the equipment took no little time and the writer describes how slowly the receiver came to life but no transmitter.

Finally they were able make contact, just before the 36 hrs ended,using a WW2 hand cranked resistance, the book says sabotage, transmitter.

Both the radio operators on the Kon-Tiki had been radio operators in the Norwegian resistance in WW2, only 2 years earlier.

If one puts LI2B into Google images quite an interesting assortment of radio related images are found (click here to view search), including QSL cards but the one I like best is this http://f6blk.net/photos/LI2Bshack_x1.jpg:

I’m sure I’ve seen an English language version, this one looks slightly cropped since the end of the ‘Earth’ wire is out of vision

Regards es 73 de

Kris G8AUU

How fascinating! Thanks so much for sharing this, Kris.

Again, apologies I didn’t get this posted prior to the 70th anniversary–I’m a tad behind (understatement alert) on email at the moment.

I have a particular affinity for The Kon-Tiki Expedition. I found a 1950s copy of the book while doing my undergraduate degree ages ago.

My 1950s copy of The Kon-Tiki Expedition in an archival cover.

The book played no small part in my fascination with anthropology–especially Heyerdahl’s version of “applied” anthropology. I went on to do my post grad work in anthropology at the London School of Economics. Indeed, I re-read that book before my finals to remind myself the significance of anthropology.

If you haven’t read The Kon-Tiki Expedition, I highly recommend you do so! Indeed, it’s about time I read it again.

I’m very curious how many SWLing Post readers have a National NC-173 sitting in their shack? Thor would tell you to take care of it, because it certainly took care of his crew!