Antena Satelor: Winter Reception

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Wednesday, February 24, 2016

Below is my most recent recording of Antena Satelor on 153 kHz out of Brașov, Romania. Receiving it is slightly more challenging during winter here in London. The signal was captured using a Lowe HF-150 radio with a Lowe PR-150 preselector and a Wellbrook ALA1530S+ antenna on 15/02/2016 at 0200 UTC.



Click here to download the recording or check my previous recordings of this station.



Update (26/02/16): A few days later the propagation from Brașov was much better and I managed grab another recording. Here's a snippet from it that I particularly like:





Update (29/02/16): Since the recording mentioned in the previous update is the best one of Antena Satelor I've ever made, I've uploaded it in full to the Shortwave Archive (almost 4 hours long!):



Some recording details:

Antena Satelor, Romania recorded in London, UK on February 25, 2016 at 0143 UTC on the frequency of 153 kHz using a Lowe HF-150 radio with the Lowe PR-150 preselector, DX Engineering NCC-1 phaser connected to two Wellbrook ALA1530S+ antennas (positioned indoors) to mitigate severe local man-made interference. The transmitter is located in Brașov, Romania and has a power rating of 200 kW. This is a local service targeted at the domestic audience. At about 0530 UTC (0730 local time in Brașov; 3 hours 46 minutes into the recording) the night-time skywave propagation path is finally completely disrupted by the sunlight reaching into Romania (26 minutes after sunrise).


This recording is yet another reward for having invested some time and effort into urban RFI mitigation.

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Submission to the Shortwave Archive Part 5: Voice of Turkey

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Friday, February 19, 2016
One of my favourite morning signals is the Voice of Turkey's 15350 kHz transmission. Starting at 0700 UTC and concluding at 1400 UTC (yes, seven hours of uninterrupted programming on one frequency!), it sounds excellent all the way through, thanks to the 500 kW signal directed towards Western Europe from their transmitters at Emirler.

Voice of Turkey transmitters at Emirler, Turkey
Below is a recording of the station made in London, UK on February 18, 2016 at 0900 UTC, on the frequency of 15350 kHz using a Lowe HF-150 radio with Lowe PR-150 preselector and a Wellbrook ALA1530S+ antenna.



Click here to download the recording // Link to the original SRAA submission

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DRM vs. analogue transmissions of All India Radio

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Tuesday, February 16, 2016
The other day, while scanning the bands, I heard a hum on 7550 kHz that was characteristic of DRM. I fired up my NewStar DR111 (which hardly gets any use nowadays, after Radio Exterior de España ceased their digital transmissions) and tuned in to the frequency. The receiver locked onto the signal immediately and "REGULAR SERVICE" came up on the text display. I had tuned into the General Overseas Service of All India Radio. The signal was very stable without any dropouts, but the sound quality was terrible. I switched back to my Lowe HF-150 and adjusted it to the first analogue frequency of All India Radio I could remember, which happened to be 9445 kHz. I kept switching back and forth between the audio outputs of the two radio receivers and could not believe the difference in quality - the analogue signal was so much better! Below is a recording of this difference: the first 30 seconds are the DRM transmission, and the rest is the analogue signal.



I then recalled that I had encountered this discrepancy in the quality of AIR's transmissions once before and tweeted about it. Below are the tweets comparing the DRM transmission on 7550 kHz to the analogue signal on 11670 kHz back in May 2015.


The reason this surprised me so much was that All India Radio didn't always sound so bad in DRM. Here's a recording I made in October 2013 on a Morphy Richards DRM receiver:



It turns out that the reason for this drastic change is the fact that All India Radio now combine two audio streams in one DRM feed (one stream per language service), as noted by Andrea Borgnino on Twitter:


It's a very cool feature of the DRM standard but unfortunately leaves around 9kbps of bandwidth per stream, resulting in rather terrible audio. The ironic part is that I don't even know how to select the second stream on my DR111 unit and would have to use one of my SDRs together with Dream to take advantage of it. I hope AIR revert to better quality DRM feeds in the future.

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