Thoughts on running a high powered RF power linear amp on an unregulated supply

Ive been thinking, at the moment i am running a 25 watt linear RF amp on a 12 volts regulated supply, i am considering running a large 300 watt linear RF amplifier on an unregulated psu, but well filtered out put stage, although i understand the no load voltage, and the voltage load line drops from such a supply, can anyone see a problem with this, the amp will have an operational range from 11.50 volts to 14.50 volts, so if kept in these perameters can anyone forsee any problems with this.

 

Hi OLIVE2222.
Thanks for your reply. I was planning on using a 300 VA toroidal transformer, primary 240 volts, secondary 12 - 0 12 - 0 and parallel these for max current, the transformer is a little over the 12 volts about 12 .80 volts AC, i thought 12 volts x 1.41 = 16.92 minus the rectifier 15.92 volts DC or there abouts, unloaded, add a modest load resistor to bring the voltage down to about 14. 50 volts or just over, i know this will drop when heavily loaded, but was planing on using somewhere in the region of 40000uf of filter capacitance in an attempt to keep the voltage above 11.50 volts.

I dont know if this would work with a load as big as that, but i would not expect the voltage to drop below this.

 

MMMM i will let you work that out, this is for CB not amateur, and yes i already know your reply.

My maplins mate let me into a little secret, he and others go above there allocated 10 - 50 watts depending on status.

A guy mobile made it in to the margate Kent repeater from sittingbourne Kent , many miles away, more than 10 - 50 watts would cover on uhf.

Any way all us CB ers use power, but mines not 300 watts yet, only a modest 25 watts.
No need for explanations i know already.

 

I called the powers to be in the UK, an idiot was wiping me out, i spoke to a top engineer working for the powers above, gave address details down to the last detail, i was told sorry not enough resources, only if it interferes with the emergency services, IE police ambulance fire brigade marine coast guard etc do we get involved, i know what people are using he said to me, but so long as it not a nuisance there is nothing we can do.

That was from a top radio governing body here in the UK .

 

Yep thats right, and you've got the correct governing body, they dont allow it, but as a top engineer said to me, we cant stop it, the guy wiping me out uses a KW of linear power, and they still said sorry mate cant help you, i was asked if he was causing any interference to any services, no i dont think so i said, ok mate sorry but cant help you, i do only use FM i dont have the money for a good multi mode radio for, mmmmm DX ing.

And if i was an amateur, i would not risk losing my status and license.

Ok what i am using even 25 watts is a no no, i get this, but if they did the rounds no one in my county would have there gear anymore it would be confiscated, oh they do return the legal gear once tested, a friend in Deal Kent lost his gear, for disturbing some services, if you live next to a police station dont go robbing banks, joke.

 

I dont use 476MHz CB band, there is no such thing in CB Radio, i use 80 channels covering frequency's from the list in the link below. What your referring to is 70cm uhf, the amataurs use this on our repeater stations, or go else where that there licence conditions allow.

http://www.g4nsj.co.uk/cb.shtml

 

I have a legal scanning receiver covering loads of frequency's, i listen in on that, well two receivers a base and a hand held unit, given to me in a terrible state i repaired them and use one in the living room, connected to a wide band antenna and a pre amp.

If that clears up how do i know what the local amateurs are doing.
One guy in the next town got a ticking off, an amateur for setting up his own repeater station, then a handful of his mates using PMR through it, but he got in trouble with a first warning, i think he heeded it.

 

Yes 70cm UHF over here is in the 430 - 450mhz band under 450 MHz, i thought TV used 600 - 700 plus MHz, channels analogue where over here and higher i think, at the moment the 300 watt linear is an idea, not for continuous use, its powered in stages from 50 watts up to 300 watts, yes the site over here sell smp's to power them 60 amps is the highest i think, the twit that keys over me has the psu and the linear, and a plug in the wall linear, tube i think.
No i am undecided if to use a unit that big, biggest ive used some years ago now was 100 watts, i thought that did well, where i live 300 watts, other than late at night would wipe out loads of peoples TV's especially on an 18' glass fiber vertical, no i dont know to be honest, part of me dont care, if you where going to die would you give a f...k, well you might, i dont know.

http://www.kcb.co.uk/shop2/index1.html

My favorite shop.

 

Well ive learnt some thing new tonight, i thought you was referring to normal TV type broadcasts, those last list of frequencies are very high, at 40db over i should think distances like that are easily attainable, not my cup of tea, but i might google it find out more about it, where stuffy over here, ive never heard of it until tonight.

A few amateurs put the pc's to good use and incorporate them into there activity's, shipping is one of them, every thing they talk about in the English channel from fishing to commercial i know about, in years gone by it was part of my job, including diving in my own time for dock side work / boats / surveys, thats about the only interesting thing amateurs here do.

 

As i say ive never heard of it, i will google it and find out more. Its not a lot of power, but a very high frequencies, yes i know NFM and WFM plus the other modes.