Category Archives: AM

BBC Research Department Report on the beverage antenna

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Many thanks to SWLing Post contributor, Kris Partridge, who writes:

[R]esearch on DTH satellite TV service took me to a public website which is an archive going back to 1934. And boy, there is so much information there ..!

So what I pass to you for the Blog is this one as a start:

http://downloads.bbc.co.uk/rd/pubs/reports/1991-12.pdf

Knowing that many of your readers/contributors have made mention of using Beverage antennas I think this may make interesting reading. The report describes a method for accessing the performance of a Beverage, long wire, receiving antenna using off-air HF broadcast signals.

[…]It looks like the lower the better. And yes, there’s some heavy maths formula in there ..!

Wow–you’re right, Kris! This is very useful information. I’ll skip the maths bit and just follow the advice! Thank you for sharing.

Oxford Shortwave Log: transatlantic MW DX catches with 200 metre Beverage – part 2

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verdad-final

Hi there, here is the second set of reception videos for my transatlantic MW DX catches using the 200 metre Beverage antenna. Most of the signals originate from the United States and Canada, however, there is also a catch from Mexico – XERF La Ponderosa – which is a personal first and another from Bogotá, Colombia – Verdad Radio. I hope you enjoy them. Please do not hesitate to contact me if you would like further details regarding the Beverage design and/or construction. in the meantime, thank you for watching/listening and I wish you all great DX!

Clint Gouveia is the author of this post and a regular contributor to the SWLing Post. Clint actively publishes videos of his shortwave radio excursions on his YouTube channel: Oxford Shortwave Log. Clint is based in Oxfordshire, England.

Oxford Shortwave Log: transatlantic MW DX catches with 200 metre Beverage – part 1

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worspectrum

Hi there, a few weeks ago I posted a couple of medium wave DX catches with the Elad FDM DUO and newly constructed 200 metre Beverage antenna. Since then (and following my trip to Brazil) I have uploaded several more catches, some of which I would like to share with you. It has become evident that the Beverage’s low-gain but high SNR properties resulted in a huge increase in the sensitivity of my entire set-up and as a result. I have achieved numerous personal firsts on the medium wave band, coupled with many other signals that I can only describe ‘best-ever reception’. If nothing else, this endevour has underlined the importance of utillising the best antenna possible for your particular circumstances. We’ve all read at some point, how, in many respects, the antenna is more important than the receiver – and these catches demonstrate how absolutely true that statement is. All of the reception videos were captured using the Elad FDM DUO running on a home-brew battery-pack and connected to the Beverage via a 50 Ohm input transformer.

Below is the first set of reception videos, most of which are signals from East Coast of the United States. However, there is also an absolutely booming signal from WGIT Puerto Rico into my QTH in Oxford UK. Part 2 will follow almost immediately, but in the mean time thanks for watching/listening and I wish you all great DX!

elad

 

Clint Gouveia is the author of this post and a regular contributor to the SWLing Post. Clint actively publishes videos of his shortwave radio excursions on his YouTube channel: Oxford Shortwave Log. Clint is based in Oxfordshire, England.

Radios With Rotatable AM Antennas?

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The Panasonic RF-2200 sports a rotatable AM/MW antenna

The Panasonic RF-2200 sports a rotatable AM/MW antenna

Many thanks to SWLing Post contributor, Mario Filippi (N2HUN), who writes:

With your broad knowledge of radios, wondering if you can add anything to this list of portable radios, past and present, that have 360 degree rotatable directional AM ferrite antennas. Reason is I am looking for an AM portable for the nightstand for nulling out unwanted AM stations while also doing a little DXing.

The list I have from data mining the ‘Net is:

New models with rotatable AM antennas:

  • CountyCom GP5/SSB,
  • Tecsun PL-360,
  • Grundig Satellite 750,

Older (vintage) models:

  • Panasonic RF-2200,
  • Panasonic RF-1150,
  • Panasonic RF-877,
  • Panasonic RF-1180
  • most RDF (Radio Direction Finder) radios that were used on boats

“Boom Box” variety:

  • Radio Shack 12- 795,
  • Emerson MBR-1,
  • Rhapsody RY-610.

[RDF radios] are kind of big, however Raytheon, Ray Jefferson, and Nova-Tech did have smaller model RDFs that could be considered table-tops).

The alternative is to build or buy a passive indoor antenna.

Maybe readers know of other models?

Thank you for your inquiry, Mario! I will do a little research of my own because you listed every model (and more) I could think of off the top of my head.

Post readers: Please comment with any models we could add to this list.

I will take all of the suggestions and make a master list to post here on the SWLing Post so it’ll be easier for others to research in the future. I’m pretty sure this question has come up before.

Which is the best? Sony ICF-2001D/2010 or ICF-SW77? Part two

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sony-test

Hi there, after the first set of recordings were analysed, the score was 4-3 to the ICF-2001D, demonstrating how similar these two great receivers are in overall performance. There were a copule of notable differences however. The synchronous detection circuit on the ICF-2001D allows the user to effectively tune through a signal in 01. kHz steps, whilst the receiver automatically locks onto either the upper or lower sideband, depending on the frequency offset. The ICF-SW77 synchronous detection system differs in that the user must tune the signal and select the sideband. The results of this test confirmed that whilst the ICF-2001D almost always retained SYNC lock, the ICF-SW77 was very prone to losing lock, which of course affected the audio quality in many cases. The other issue was with the ICF-SW77 in that the narrow audio bandwidth filter often seemed to deliver ‘muddy’ audio. Whilst this feature proved to be excellent in terms of mitigating adjacent channel QRM, it also reduced signal clarity/ audio discernibility a little too much in my opinion. However, overall, sensitivity and selectivity was very similar between both radios – in fact, one recording had to be judged a draw (Radio Bandeirantes, Sao Paolo on 9645.4 kHz) – I simply couldn’t split them. Part two of the reception testing follows, using signals from Canda, DR Congo, Brazil, Cuba and Peru.

I hope you enjoy the recordings – text links and embedded videos follow below:

 

 

 

 

 

 

Clint Gouveia is the author of this post and a regular contributor to the SWLing Post. Clint actively publishes videos of his shortwave radio excursions on his YouTube channel: Oxford Shortwave Log. Clint is based in Oxfordshire, England.

Which is the best? Sony ICF-2001D/2010 or ICF-SW77? The halfway score

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Hi there, here is a summary of the first half of tests comparing the Sony ICF-2001D against it’s replacement the ICF-SW77. Both receivers are widely acknowledged as being amongst the best shortwave portables ever made, but how close are they in performance? Is there a clear winner after the first 8 reception tests? I hope you enjoy the summary video. Links to the first half of reception tests follow again, below, whilst the second half will follow in a separate post. Thanks and good DX to all.

 

Clint Gouveia is the author of this post and a regular contributor to the SWLing Post. Clint actively publishes videos of his shortwave radio excursions on his YouTube channel: Oxford Shortwave Log. Clint is based in Oxfordshire, England.

Oxford Shortwave Log: DXing in the tropical rainforest of Pará, Brazil – part 2

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img_9956pl-680

Hi there, here is part 2 of my reception videos taken in the tropical rainforest of Pará, Northern Brazil. As I mentioned in my previous post, I took a Tecsun PL-680 with me on the trip because I didn’t want to risk losing or trashing one of my precious vintage portables but also because of the following:

  • It can handle a longwire very well without overloading (I actually only used a 5 metre wire)
  • An excellent synchronous detection circuit and audio bandwidth filtering options
  • Excellent sensitivity, as demonstrated by the many DX reception videos on YouTube
  • If it got lost or damaged it would be a pain, but not difficult to replace

So, what can you hear in the jungle? Part 2 of my group of reception videos follow below – I hope you enjoy them.

Tropical rainforest DX in Pará, Brazil: RMI Overcomer Ministry 11530 kHz

 

Tropical rainforest DX in Pará, Brazil: Radio Tamazuj 11650 kHz, Madagascar

 

Tropical rainforest SW in Pará, Brazil: Radio Nacional Brasilia 11780 khz

 

Tropical rainforest DX in Pará, Brazil: R Aparecida 11855 khz (TX distance 2430 km)

 

Tropical rainforest SW in Pará, Brazil: R Brasil Central 11815 kHz, Goiania

 

Tropical rainforest DX in Pará, Brazil: Voice of Turkey 11980 kHz

 

Tropical rainforest DX in Pará, Brazil: Radio Dabanga 13800 kHz, Madagascar

 

Clint Gouveia is the author of this post and a regular contributor to the SWLing Post. Clint actively publishes videos of his shortwave radio excursions on his YouTube channel: Oxford Shortwave Log. Clint is based in Oxfordshire, England.