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London Pirate Radio / tf live gone now station fm on the same frequency
« Last post by radionortheast on August 25, 2026, 10:21:06 am »
this is abit confusing, I heard only 7 stations when I tuned over the north London reciever at the weekend, I actually thought I might hear more with it been on an evening. Power 105 90.0, 94.2 station fm, 94.6 underground bass, 96.1 s dance, 99.6 venture, 99.8 supreme, 101.2 unique, I kind of think vibes fm might be there too but I forgot to check., compared with easter there were so many there..I guess august maybe the time they take stations off air, I always used to think it was april at christmas I don’t know if I might be thinking of stations in ireland. I suppose the fewer stations out there the eaiser it is to do a spot of hovering
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1611 seems to be the strongest, number of others too on other frequencies
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Technical Corner / Trying to find the medium wave broadcaster
« Last post by radionortheast on August 22, 2026, 10:07:25 am »
I used to have one of those electronics kits from the science musume, i’ve been trying to find the circuit, they used 1 transistor, its one of the earliest things I would play about with. I found a circuit here, it looks simliar the ones I had i’m pretty sure they used a little audio transformer, I guess its abit different. Apparently these circuits aren’t the best they maybe have fm modulation aswell as am, I don’t know how they would sound on a radio with digital tunning. But i’m pretty sure I used to tune to 200 in 1, on a pocket radio, all the pocket radios had digital tunning.

I did find it pretty funny on here it is listed as the radio station  :o in the science museum one I think it was called the am or mw broadcast station, I’d spend many hours listening to music through these things, glow worm, 2unlimited all 90’s euro dance, i’d butched a 3.5mm headphones jack, to get it to connect to my boombox, before music could be only played through the speaker, which acted as a microphone which wasn't as good. It was how you’d tune these things is you’d put your radio close to the speaker, when you heard a squeel you would be tuned to the transmitter.
https://www.scribd.com/document/372367099/Electronics-Lab-30-in-1-Velleman#page=40
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My bad the GIF shows only voltage and electric fields, but it remains true where volts are minimum current is maximum (centre for dipole and GPA) for a correctly set up 5/8 wave GPA the current centre shifts upwards on the wire (and you get a smaller out of phase current flow lower down)
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yeah I spent ages trying to find the magic fly, it was on some album I bough on tape from book depo years ago, it was remix then the original is apparently from 1977. They’d taken to remixing jean michel jarre aswell on the album, cocoon by timerider was there too was the theme song for the hit man and her. Maybe they might put on italo disco then chripy chripy cheep cheep  8)
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It seems there are a few Brits who are very close to the MW Nederlandse Middengolfpiraten

I prefer this video ;) Good track, maybe they can play it for us ?

https://www.youtube.com/watch?v=C95MWM30cYo&list=RDqBrjysAxwo0&index=2

Unless they clearly and slowly say the stationID it can be difficult to get an ID on station name.
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maybe a transmission could be heard by noone and be on a band were it couldn’t be heard by anyone,

I have to admit to not understanding this above, sorry.

The area of greatest radiation on any given TX antenna is known to be where the current flow is highest. TX antennas have alternating current and voltages and they exist at different points on the antenna.

For a 1/4 wave, let's say a GPA.. the highest current is at the feed point.

The same for a dipole, maximum current is in the middle. You can see this current and voltage oscillation on this GIF :

You can see in the centre of the 2 poles the voltage (pink) remains at zero, no movement, which means current is at maximum. (and vice versa there is very little current at the ends of the poles) E is the electric field from which we determine the polarization, in this case horizontal.



Whilst the feedpoint can change as in for example a half wave that is fed at the end the current centre remains the same the centre of the antenna.

As I understand many antenna for MW are either 1/4 waves or coil loaded shortened 1/4 waves. This means the highest current is at the feedpoint.

This explains why if you fed a 1/4 wave from the top of a tower block it would perform very well as the current centre is up high. However if you have a ground mounted vertical
1/4 wave (full size or coil loaded) your maximum current radiation is at the bass of the antenna close to or on the ground. This has a few problems associated with it.

1) Max radiation probably coincide with max obstacles that can attenuate the signal, houses and other buildings are the obvious ones.

2) As your current centre is near or on the ground you will have significant ground losses, this basically means the earth below your antenna is part of your antenna system and the earth is very lossy, and some of your RF turns into minuscule amounts of heat in the ground itself warming up the earthworms.

As such any 1/4 wave antenna is a serious compromise without something like an ideal of 40 x 45m long radials on or just below the ground.

The rule is put as many and as long ground radials as possible, and if you cannot put long ones put more short ones.

In any event it will be a compromise. A tower block would be great but of course, there are vast numbers of people who might want to mess around with MW
who won't be going anywhere near a tower block with all the practical and probably legal problem it can create.

You can load a vertical antenna higher up than the base, this increases current flow higher up the antenna but is a bit more complex to calculate and has practical tuning
issues as you coil is maybe at 9m high instead of within hands reach. You can also add for example a cross shape at the top of the antenna and connect that directly to the radiating element
(soldered) this influences the current distribution and increases current flow toward the top of the antenna where there are less obstacles and further from lossy earth.

Zozo bloke used some kind of really short antenna but avoided some problems by having the current centre above local obstructions and therefore got good performance from it. I think it was called a Sandpaper antenna but seemed to be some kind of modified commerical ham radio design, I might be wrong on the zozo details though but I think that's about right..
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maybe a transmission could be heard by noone and be on a band were it couldn’t be heard by anyone, I suppose it could go into some equipment nearby cause undesired operation, I don’t know if 1w or 4w could do this on mw, its kind of an unknown, I suppose its just the rf field if its close enough.
Mw aerials tend to be long, from what I gather the most signal goes out from the middle of the wire, unless you had a huge garden it would be hard to get away from a road, its something thats in the air or going along a fence, the fence would hide it, but not the rf field.
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nigel seemed to know were they are, :D at least the ones on mw, maybe they all hang out listening to silicon dream holding giant beer jugs in the air when their not on air. ;D I do see the 3.5m band ones hanging about on fm dx webservers when theres tropo between the uk and holland, i’ve seen them comment on fm dx watchdogs, its private now I guess we won’t beable to see anymore.

https://www.youtube.com/watch?v=J-WyImt8AJE
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