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Transmitter power
Posted: Sat Jun 20, 2020 4:08 pm
by netant2000
Hi all,
A bit of a weird question from me.... ...anyone got any idea what the most powerful transmitter wattage used by a pirate in London or surrounding counties has been in the past
I'm thinking its around 300 watt mark?
Weird question I know, I'm just curious
Thanks all, stay safe
Sent from my SM-G975F using Tapatalk
Re: Transmitter power
Posted: Sat Jun 20, 2020 4:47 pm
by XXL
Usually 300w now days coz they’re all so low down.
Re: Transmitter power
Posted: Sun Jun 21, 2020 6:57 am
by teckniqs
Just over 950w from an outer west London tower block about 5 years ago.
....I've never heard of anyone using any more than that in London during my 25 years of radio.
Re: Transmitter power
Posted: Sun Jun 21, 2020 1:33 pm
by XXL
Who the fuck was that ? Can’t of lasted long.
Re: Transmitter power
Posted: Sun Jun 21, 2020 2:04 pm
by teckniqs
I won't say who it was but many people on here know who.
They had the rig hidden behind kitchen units in someones flat and the coax and power running down from the roof to the rig, it lasted for a considerable while before they relocated it a couple of miles further west.
...I live in Worthing over 50 miles away in West Sussex with massive hills directly north in the way of London and it was almost cystal clear by Worthing pier!
Re: Transmitter power
Posted: Mon Jun 22, 2020 1:23 am
by Albert H
In the early 80s, when the 24-hour stations started from Church Road Crystal Palace, there was a very big Colinear Aerial put up. The aerial had significant gain, and the biggest rig that was run into it was around 650 Watts - the ERP was around 1.5 kW. There were reception reports (and tapes) sent in from northern Germany, Belgium and France.
Re: Transmitter power
Posted: Mon Jul 06, 2020 9:18 am
by nrgkits.nz
Kiss FM in Belfast late 80’s had an eirp of 1.2 mega watts using an array directional yagi’s, I think the gain was around 26db
Re: Transmitter power
Posted: Mon Jul 06, 2020 9:52 am
by teckniqs
That's very true, but it's a very long way away from London and the surrounding counties.
Re: Transmitter power
Posted: Wed Jul 08, 2020 1:15 am
by Albert H
nrgkits.nz wrote: ↑Mon Jul 06, 2020 9:18 am
Kiss FM in Belfast late 80’s had an eirp of 1.2 mega watts using an array directional yagi’s, I think the gain was around 26db
You're roughly right. The exciter for that rig was an NRG PLL Pro II. Miles tried the Broadcast Warehouse PLL+, but it just went into wild self-oscillation and the PLL wouldn't lock. (Moral: Don't use "at frequency" generation for higher power stuff!). He picked up an NRG ready-built board from me (in North London at the time) and rushed over to Ireland with it, because he had to get Kiss on in a hurry!
Those stations were true "border blasters" and Kiss was probably the most powerful pirate ever, anywhere!
Re: Transmitter power
Posted: Fri Jul 10, 2020 12:54 am
by Tec1 87.5fm London
1000w in to A .j pole On 87.5 ... 4 years a go
Re: Transmitter power
Posted: Fri Jul 10, 2020 12:19 pm
by famefm
Tec1 87.5fm London wrote: ↑Fri Jul 10, 2020 12:54 am
1000w in to A .j pole On 87.5 ... 4 years a go
So that's why I could pick it up in Wiltshire at that time. I wonder how much power the present station on 87.5 livefmuk is running?
Re: Transmitter power
Posted: Fri Jul 10, 2020 12:49 pm
by teckniqs
Probably just a stolen 150w box, no point in wasting a 300w box for that shite .....even if it was free.
Re: Transmitter power
Posted: Fri Jul 10, 2020 1:20 pm
by teckniqs
XXL wrote: ↑Sun Jun 21, 2020 1:33 pm
Who the fuck was that ? Can’t of lasted long.
Tec1 87.5fm London wrote: ↑Fri Jul 10, 2020 12:54 am
1000w in to A .j pole On 87.5 ... 4 years a go
Now you know...
Re: Transmitter power
Posted: Fri Jul 10, 2020 1:51 pm
by famefm
Actually the big signal did last some time I think it was at least 6 months and as for the presant 87.5 station they have lasted for some time now 3 months and counting .I moving in 3 weeks time to 100 miles north of London so don't have long left to listen to London fm pirates
Re: Transmitter power
Posted: Tue Jul 14, 2020 1:26 pm
by Sparki
I know of one that came on years ago that for a day banged out a 300 watter it got into parts of Watford and a little into London which was quite impressive from Kent and by Kent I mean on the tip of the seaside. They did this test for one day but never came on as the DJ's were a let down apparently. I'm not sure how far 300 is meant to go obviously a long way but would you say getting to Hertfordshire and a tiny bit of London sounds about right? or was it to do with luck and nothing in the way of it?
Re: Transmitter power
Posted: Tue Jul 14, 2020 9:54 pm
by Username
Im a delivery driver, well was until lockdown , i drive all over the country , must be talking above about the same signal on 87.5 around 5 years ago i had them from the south coast all the way to a place called Billesdon which is just outside Leicester and had 87.5 crystal clear the whole way
Re: Transmitter power
Posted: Tue Jul 14, 2020 10:01 pm
by Username
just to add - 94.2 a couple of years ago I noticed were getting out same sort of distance
More recently tho just before lockdown I noticed 97.9 clear from Crawley to past Luton clear as a bell
Re: Transmitter power
Posted: Wed Jul 15, 2020 12:06 am
by thewisepranker
Tec1 87.5fm London wrote: ↑Fri Jul 10, 2020 12:54 am
1000w in to A .j pole On 87.5 ... 4 years a go
I picked this up on top of Devils Dyke playing jungle, the signal was really strong. I've got it burned in my memory that the DJs were identifying the station as UK's Finest, although I know that it was actually a different station by that time. I then drove to Brighton and ended up on the beach (on the stones) and could still get it but it was obviously weak.
Re: Transmitter power
Posted: Sun Jul 19, 2020 2:13 am
by Albert H
Sparki wrote: ↑Tue Jul 14, 2020 1:26 pm
I'm not sure how far 300 is meant to go
300 Watts travels exactly the same distance as 3 Watts, if each is put into the same aerial. The power doesn't change "range".
VHF signals always go to the horizon.
You extend the horizon by putting the aerial as high up as you can. The transmitter power
just changes the signal-to-noise ratio. The higher the power, the better the S/N. A 1 Watt signal will go to the horizon -
just like a 1kW signal - but probably won't be able to be heard above the noise floor. As you increase the transmitter power, you flatten the noise more and more, making your signal able to be heard above the noise at a greater distance from the transmission aerial.
The only VHF exception to that range rule is when you get weird atmospheric conditions (usually in the summer months), and VHF signals go halfway around the world! This is just a freak set of circumstances and is not useable for broadcasting due to the transient nature of the phenomena!
Re: Transmitter power
Posted: Sun Jul 19, 2020 11:14 am
by XXL
Albert H wrote: ↑Sun Jul 19, 2020 2:13 am
Sparki wrote: ↑Tue Jul 14, 2020 1:26 pm
I'm not sure how far 300 is meant to go
300 Watts travels exactly the same distance as 3 Watts, if each is put into the same aerial. The power doesn't change "range".
VHF signals always go to the horizon.
You extend the horizon by putting the aerial as high up as you can. The transmitter power
just changes the signal-to-noise ratio. The higher the power, the better the S/N. A 1 Watt signal will go to the horizon -
just like a 1kW signal - but probably won't be able to be heard above the noise floor. As you increase the transmitter power, you flatten the noise more and more, making your signal able to be heard above the noise at a greater distance from the transmission aerial.
The only VHF exception to that range rule is when you get weird atmospheric conditions (usually in the summer months), and VHF signals go halfway around the world! This is just a freak set of circumstances and is not useable for broadcasting due to the transient nature of the phenomena!
Albert that is a load of rubbish. If it was a perfect world, yes 3w would go the same distance. 300w would penetrate through things a lot further out, thus the signal will travel further.