Tag Archives: Mediumwave

Standing Inside a Broadcast Transmitter While it’s ON!

I stumbled across a video from the fabulous Mr Carlson’s Lab YouTube channel. If you haven’t check out this channel before, and you are really eager to learn more about electronics, this is a wonderful YouTube site.

So, in the latest episode, Mr Carlson takes us on a tour of a very large Gates BC-250-GY broadcast transmitter from the 40’s era. Lots of big tubes, transformers and capacitors! This is an old mediumwave transmitter that he has restored. Although the technology has changed markedly since the 1940s, the basic principals of transmission are still present. And, interestingly, he points out that this particular unit was in regular service right up until as recently as 2003!

It’s an interesting show and even if you can’t grab onto all the technical information presented, I think you will enjoy looking at technology from a past era.

73 and good DX to you all,

Rob Wagner VK3BVW

Rob Wagner, VK3BVW, is the author of this post and a regular contributor to the SWLing Post. He also blogs at the Mount Evelyn DX Report.

Gary’s mediumwave DX FSL antenna phasing experiment

Many thanks to SWling Post contributor, Gary DeBock, who shares the following note about his latest FSL antenna experiment:

Medium wave DX FSL antenna phasing experiment– 1593-CNR1 (Changzhou, China, in Mandarin) boosted up to strong (S9) peaks by two 5 inch “Frequent Flyer” FSL’s at 1435 UTC on February 25th in my frozen back yard in Puyallup.

Unlike other high gain MW antennas, the FSL’s can provide cumulative gain at very close inductive coupling ranges.

Click here to download and play MP3 recording.

Amazing, Gary!  Thank you for sharing this excellent bit of DX!

Click here to read more about Gary’s FSL antennas.

Video: History of the Shipping Forecast

Many thanks to SWLing Post reader, George, who writes:

With all of the recent postings about the Shipping Forecast, I thought I’d share this excellent little video produced by the Met Office:

Click here to view on YouTube.

Thank you, George!

Video: Juan touts Panasonic RF-2200 performance & filter shapes

Many thanks to SWLing Post contributor, Juan Pablo Carlino, who writes:

Hi. I own one RF-2200 after buying it in eBay in March 2008. Since then it became my favourite portable radio and as everybody [has commented], its a pleasure to hear MW with it.

I explain this due to the fact that it has a good rotative ferrite antenna and also because the narrow and wide filters have a suitable shape for MW: at least in my country each MW is spaced from the other by 10 KHz, so you don’t need a very sharp filter. The narrow one is not so narrow, just enough to attenuate maybe 6 db the splatter from the louder station and not loosing audio quality.

When you tune around you have the impression that the filter shape suites perfectly for MW, making the audio quality very pleasant. I would never sell it. If you are interested i’ve captured a short clip while playing with it outdoor on 7 MHz band, hearing ham stations on AM, SSB and CW.

Pay attention to how loud and clear i was hearing stations at 400 Km in AM:

Click here to view on YouTube.

Many thanks for sharing your thoughts, Juan!

I agree with you completely. At least here in countries where MW stations are spaced at 10 kHz, I find the RF-2200 a mediumwave DX boss!

I’m constantly amazed with the RF-2200’s MW sensitivity and selectivity–and low noise floor. That combo, along with the filter shapes Juan mentions and the excellent built-in full-fidelity speaker make for a proper listening experience.

As I’ve said before, the RF-2200 is a radio with fortitude and purpose.

The only place I’ve ever really searched for an RF-2200 is eBay. I like eBay, because if you receive a faulty unit, you can typically return it or have some sort of recourse (as long as the seller accepts returns).

I would only buy an RF-2200 (or any vintage solid-state rigs) from a seller that has near 100% ratings with a number of radio sales in their past.  That is, if you’re seeking a working unit.

Though the RF-2200 is vintage and thus might eventually need repair. It’s ultimately reparable by a skilled technician, though.  My buddy Vlado, for example, has repaired 2200s in the past–indeed, we cracked my RF-2200 open a few months ago to clean contacts.

Panasonic RF-2200s typically cost between $175-300 for one that’s mechanically and cosmetically sound. Of course, NOS units go for much more and units with faults sell for much less.

I expect my RF-2200 will outlast me!

Click here to search for RF-2200s on eBay.

With switch from AM to FM, some Polynesians now in the dark

(Source: Southgate ARC)

Some inhabitants of French controlled Polynesia are unhappy at the switch over from Medium Wave AM to VHF FM broadcasting

Radio New Zealand reports Radio Polynesie Premiere switched to an all FM service at the beginning of December, leaving pockets of inhabitants in valleys and on remote atolls without any local radio service.

The broadcaster added five FM transmitters to its network of 48 to improve its reach but in an area the size of Europe, the signal fails to reach all communities.

Concern has been expressed that vital weather warnings are no longer heard.

The mayor of Makatea in the Tuamotus Julien Mai said there is a risk to public safety because people have always been advised to have an emergency kit that includes a radio when severe weather strikes.

Source:
http://www.radionz.co.nz/international/pacific-news/321809/loss-of-am-radio-irks-french-polynesia