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Old 28th Nov 2021, 10:52 pm   #101
William78
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Default Re: Radio Caroline Power Increase

At midday today I could get Caroline on my Roberts R600 and also my Panasonic Rf1105 Portable just with their internal ferrite rod aerials. It was not that strong but you could listen to it well enough. Putting my 70cm MW tuned loop near made a major difference, it was at comfortable strength, very pleasant to listen to.
Before the power increase I could not hear Caroline without the loop, (in the day anyway).

With the Murphy B40D and its "long" wire at midday again, Caroline was a good signal with a lot less noise than before the power increase.

Last night the signal strength went up so I could listen on the portables without the loop but the signal was subject to fading, even so there were long periods of good signal strength. The loop does not seem to make much difference at night, maybe on deep fades but not much.

The same story with the B40D at night. Signal a lot stronger but with fading.

Now that they have boosted the power this seems to be very similar to when they were broadcasting from the Ross Revenge back in the 80s. Night time reception might even be better today.

William
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Old 29th Nov 2021, 10:05 am   #102
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Default Re: Radio Caroline Power Increase

I have noticed an improvement with the new 648 KHz transmitter especially during the day. It use to be just on the noise level now it's audible but still weak.

I was listening yesterday afternoon on my 1966 Bush TR130 which would have been impossible before the power increase.
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Old 29th Nov 2021, 10:09 am   #103
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Default Re: Radio Caroline Power Increase

I got a very decent signal in the car in West Oxfordshire. I don't know how well it would hold up on a long journey, but it was nice to hear.

I love analogue radio and find the idea of getting Caroline on MW exciting.
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Old 29th Nov 2021, 12:39 pm   #104
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Default Re: Radio Caroline Power Increase

Listening around 21:00 yesterday on my 840A and longwire, Caroline was a good strong signal but with a repetitive, choppy fading every second or so - the sort of effect you get when there are two carriers only a Hertz or so apart which are beating together - which rendered it not of entertainment-quality.

My little Sony clock-radio also detected the same effect.

Now, it's only just detectable above the noise on the 840A.
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Old 29th Nov 2021, 2:54 pm   #105
Junk Box Nick
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Default Re: Radio Caroline Power Increase

Quote:
Originally Posted by paulsherwin View Post
I don't think there are any co-channel stations in Europe on 648 now...
I think Radio Murski Val in Slovenia is still on 648.

Co-channel interference has traditionally been more of a challenge than fading here in the evening.
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Old 29th Nov 2021, 4:50 pm   #106
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Default Re: Radio Caroline Power Increase

Quote:
Originally Posted by Sideband View Post

The car radio could also receive it quite well but for some reason, AM through the car radio sounds awful probably due to the limited IF response....just sounds mushy and flat
This muffled AM sound is often due to low pass filtering of the audio AFTER demodulation, rather than the IF.
Cutting out a relevant capacitor to Gnd can greatly improve AM audio.

What the manufacturers were up to I do not know?

Audio above 2kHz greatly helps intelligibility of speech in a vehicle with road noise etc, yet the car radio manufacturers choose to attenuate AM audio above 2-3 kHz !
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Old 29th Nov 2021, 6:18 pm   #107
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Default Re: Radio Caroline Power Increase

Just tried again with the 840A: Caroline coming in well, though still with the previously-mentioned 'choppy' fast fading and a dose of sideband-splash from adjacent stations. I found that backing-off the RF Gain and then turning the AF Gain to near maximum tended to improve this - am now wondering if there's a lack of AGC action causing overload in either the mixer or the IF amp. Will have to do some AGC-line checkouts!

I also plan on building an experimental tuned-loop antenna using plastic water pipe and 1mm trunking-type 'singles' wire; in days gone by we wound such loops on old orange-boxes or 1-gallon plastic engine-oil containers.
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Old 29th Nov 2021, 8:05 pm   #108
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Default Re: Radio Caroline Power Increase

I can get Radio Caroline here in Nottinghhamshire, the signal is not too bad
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Old 29th Nov 2021, 8:51 pm   #109
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Default Re: Radio Caroline Power Increase

Quote:
Originally Posted by colourking View Post

This muffled AM sound is often due to low pass filtering of the audio AFTER demodulation, rather than the IF.
Cutting out a relevant capacitor to Gnd can greatly improve AM audio.

What the manufacturers were up to I do not know?
That's very interesting. I hadn't thought of that. Just why any manufacturer would want to attenuate an already limited bandwidth isn't clear unless it's to help reduce the effect of interference.

Typically I can't get to the radio as it's part of the dash and also has buttons that control certain functions of the car.......
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Old 29th Nov 2021, 11:30 pm   #110
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Default Re: Radio Caroline Power Increase

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Originally Posted by Aub View Post
1kw to 4kw is only 1 S point increase. It seems better than that though.

Aub
My thoughts too. It's come up so dramatically here that it sound more like 10 or 12 dB.
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Old 29th Nov 2021, 11:35 pm   #111
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Default Re: Radio Caroline Power Increase

After some checks I can report Caroline is good in the nite but unfortunatley no trace of a signal indoors in the day tomorow il try it in the shack on the 817 see how well it comes in on that. I apologise I couldn't go up there today not feeling up to it
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Old 1st Dec 2021, 11:19 am   #112
Junk Box Nick
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Default Re: Radio Caroline Power Increase

Had a listen to Caroline last night and, though stronger than previously, had the 0.5 second beat ‘choppy’ effect referred to above that I have noticed regularly in the past, and that, frankly, makes it unlistenable. This is far more irritating than the long fades and phase distortion we used to put up with years ago.

Occasionally, under the previous 1kW it was good in the evening but this has probably been down to propagation with the skywave from the co-channel stations reduced.
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Old 1st Dec 2021, 11:29 am   #113
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Default Re: Radio Caroline Power Increase

Here, I find it much more listenable in the day than after dark - the daytime signal is weak, but fairly clean.
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Old 1st Dec 2021, 1:00 pm   #114
Junk Box Nick
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Default Re: Radio Caroline Power Increase

With 1kW driving the quarter wave vertical the daytime signal here (distance: 150 miles) has been quite acceptable for listening. The improvement with the change from the original standby umbrella was noticeable.

Listening today it is good and strong and for most listeners who want a bit of company rather than a hi-fi experience it would be more than acceptable.

I read elsewhere the antenna has a bit of a null. This might be due to the other masts. Perhaps that Ordfordness is ESE of me and in the days of the World Service I would be precisely on the back of the beam has something to do with it.
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Old 1st Dec 2021, 5:53 pm   #115
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Default Re: Radio Caroline Power Increase

Today I had to drive East from my abode and so got to see what daytime/Dusk reception of Caroline was like in the car.

I went as far East as Maidenhead at lunchtime - Caroline was a good signal except for some total noise-wipeouts when driving under power-lines.
Coming home along M4 around dusk, reception was a lot worse - a mix of slow and fast fading and general QRM. Daytime fading is tolerable because the signal-fade is replaced by relatively-innocuous low-level 'mush' - at night the fade seems to be replaced by loud QRM!

[the above was received using a standard-fit 2018 MW/LW/FM/DAB Meridian car-radio fed from the standard-fit 'sharks-fin-with-integrated-amplifier' roof antenna]

I'll be giving Caroline another listen this evening on my 840A - and have a WWII-era Pye PCR in the lab undergoing a capacitor-transplant - will be interesting to see how well that works at getting Caroline!.
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Old 1st Dec 2021, 8:32 pm   #116
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Default Re: Radio Caroline Power Increase

Quote:
Originally Posted by G6Tanuki View Post
[the above was received using a standard-fit 2018 MW/LW/FM/DAB Meridian car-radio fed from the standard-fit 'sharks-fin-with-integrated-amplifier' roof antenna]
.
Are you sure the 'shark-fin' is actually used for MW/LW?
I suspect the aerial is printed on a window. Try holding a smartphone (with the display on) around the outside of the car (with the car radio on a weakish AM station) and see where its AM interference peaks!
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Old 1st Dec 2021, 10:33 pm   #117
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Default Re: Radio Caroline Power Increase

Im in north devon ive just managed to pick up caroline for the first time, my Hacker Herald and Roberts R303 picked it up fairly well it was fading in and out a bit but listenable. Anybody else in devon picking it up ok.
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Old 2nd Dec 2021, 11:52 am   #118
60136 Alcazar
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Default Re: Radio Caroline Power Increase

Caroline on 648kHz clear and listenable in daytime on a Goodmans Module 150 dating from 1978, here on the 'wrong' side of Beeston hill in Leeds. Signal path entirely over land at a range of 175 miles.
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Old 4th Dec 2021, 1:16 pm   #119
Junk Box Nick
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Default Re: Radio Caroline Power Increase

Interesting brief article with pictures on the Radio Caroline site. It states that the DX25 is running into the reserve umbrella antenna. This might be part of the method of achieving 4kw ERP given that the Tx has had to be modified as in standard state its lowest power output is 10kW. The umbrella will also not be suffering from the null. 648 remains a good signal here.

Scroll down below the reception report:

http://www.radiocaroline.co.uk/#home.html
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Old 5th Dec 2021, 7:07 pm   #120
johnmarshmanagain
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Default Re: Radio Caroline Power Increase

Received quite audibly here in Limoges after dark on the car radio
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