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Vintage Radio (domestic) Domestic vintage radio (wireless) receivers only. |
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12th Mar 2018, 3:07 pm | #21 |
Heptode
Join Date: Mar 2014
Location: Meath, Ireland
Posts: 551
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Re: Low Power MW DX?
This is a short list of stations received at entertainment quality here today, there are a few missing but it gives an idea of conditions.
Spirit 549Khz Radio 4 720Khz BBC Scotland 810Khz BBC Radio Lancashire 854Khz BBC Wales 882Khz Key 2 Manchester 1152Khz Absolute 1215Khz BBC Radio ulster 1341Khz Manx Radio 1368Khz Gold 1458 Khz (mixing with another unknown station) BBC Radio Merseyside 1485Khz Radio city talk 1548Khz Radio used is a Hitachi marine radio. I hope this is of interest, John Joe |
12th Mar 2018, 3:14 pm | #22 |
Moderator
Join Date: Jun 2003
Location: Oxford, UK
Posts: 27,943
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Re: Low Power MW DX?
Dublin really isn't that far from NW England, with a sea path. W Scotland is a bit further away, but there's still a sea path, and BBC Scotland uses a pretty meaty 100kW transmitter at Westerglen as it has to get up to the Highlands.
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12th Mar 2018, 7:16 pm | #23 |
Octode
Join Date: Mar 2006
Location: Bracknell, Berkshire,UK.
Posts: 1,172
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Re: Low Power MW DX?
For us radio amateurs who regularly work all over the place with as little as 5W on 160m it hardly surprises me that many of these 1KW or so MW transmitters with antennas far better than most amateur ones can also be heard at long distances.
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12th Mar 2018, 7:26 pm | #24 | |
Dekatron
Join Date: Apr 2012
Location: Wiltshire, UK.
Posts: 13,998
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Re: Low Power MW DX?
Quote:
Then as analog-TV faded away the noise-of-the-current-millennium became SMPS and CFL-bulb hash! |
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12th Mar 2018, 10:08 pm | #25 |
Pentode
Join Date: Jul 2016
Location: Edinburgh, Scotland, UK.
Posts: 110
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Re: Low Power MW DX?
Thanks for the confirmation guys. If Simon can pull in Fife and Aberdeen sub 2kW from Bristol then maybe it's not such a freak as I thought. The clear channel argument is one I hadn't considered. WABC on 770kcs at 50KW sets an interesting context. I'd love to think that BBC Scotland on 810kcs at 100kW could be heard stateside.
I usually think of DX in the context of the unconventional aerial arrangements of my youth (a bean-can on a wire hung out a 3rd story window) chasing fading signals like Laser 555 (?) around the dial. What surprised me was that 1116kcs was solid entertainment quality (except the odd bit of powerline hash) all the way down the road. Maybe that's the advantage of no cochannel interference? John Joe -are those daytime reports? Even given a sea-route, pulling in the lower power stations at the high end of the dial is still impressive if they are use able signals. MW ain't dead!! Interesting point about the TX on the M5 Does that mean that Droitwich R4 on 198kcs is horizontally polarised? I've never passed the M5 site, but I know the Westerglen site is a vertical mast with a capacity hat. I 'think' the Burghead site is the same, although it's a while since I passed closeby. Is R4 horizontal in England and Vertical in Scotland? Does it make much difference? As an experiment I rotated the set 90 degrees so that the ferrite rodd was vertical and the signal definitely dropped. .. |
12th Mar 2018, 11:10 pm | #27 |
Heptode
Join Date: Mar 2014
Location: Meath, Ireland
Posts: 551
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Re: Low Power MW DX?
Hi Croozer,
Yes this was today around 1.30pm just before I posted |
13th Mar 2018, 12:48 am | #28 |
Dekatron
Join Date: Apr 2011
Location: Cornwall, UK.
Posts: 13,454
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Re: Low Power MW DX?
Droitwich LW is vertically polarized, a T antenna, the vertical section is less than 1/4 wavelength long, the top horizontal section adds capacitance to the system, the upshot of that extra capacitance along with taking other things into consideration is more radiated power, to save me wearing my fingers out I've included a link that will show the basics of the T antenna including current distribution:
https://en.wikipedia.org/wiki/T-antenna Lawrence. |
13th Mar 2018, 10:24 am | #29 |
Nonode
Join Date: Jan 2004
Location: 1966-1976 Coverack in Cornwall and Helston Cornwall. 1976-present Bristol/Bath area.
Posts: 2,965
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Re: Low Power MW DX?
This morning on the car radio I picked up Pulse 2 from the 0.74Kw transmitter at Vicars Lot near Huddersfield. This uses a vertical mast as the medium wave radiator with the FM transmitting aerial for Pulse 2 mounted on top of the medium wave radiator. The IBA successfully used this arrangement at quite a few sites across the country.
When conditions are really good to the North I have also received the low powered local Scottish commercial stations such as Tay 2, West Sound, North Sound and MFR2 from Inverness all around 1Kw or less and on my car radio whilst parked in my works car park near Bath just before I go into work. I am making the most of this low powered MW DX before these transmitters are switched off.
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Simon BVWS member |
13th Mar 2018, 7:27 pm | #30 |
Dekatron
Join Date: Jul 2007
Location: Penrith, Cumbria, UK.
Posts: 3,687
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Re: Low Power MW DX?
The optimium (electrical) height for a vertical radiator to give maximum ground-wave field-strength is 5/8 wavelength (0.625). Above this, secondary high-angle lobes are produced and the ground-wave falls off dramatically.
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Regds, Russell W. B. G4YLI. |
13th Mar 2018, 7:38 pm | #31 | |
Dekatron
Join Date: Jul 2007
Location: Penrith, Cumbria, UK.
Posts: 3,687
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Re: Low Power MW DX?
Quote:
Didn't Blaw-Knox make bulldozers?
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Regds, Russell W. B. G4YLI. |
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