Contesters and DXers use kilowatt amplifiers to help cut through pileups. Running a big amplifier is not for the newcomer as any defect in the station will become immediately known once you switch on the amp. Also for maximum efficiency amps need to be run on 220 volts instead of 110.
Canadian hams need an advanced license to run more than 250 watts.
Most rigs run 100 watts and that’s plenty for most casual and personal operation. you can easily work the world with a 100-watt rig.
QRP is defined as 5 watts or less on CW or 10 watts or less on SSB.
At VE3HG I’ve been running QRP for over a year now and during a variety of contests I can say I don’t notice a difference between 5 watts and 100 watts on CW.
On SSB it’s a different story but that hasn’t precluded me from working Australia and all of Europe on 5 watts SSB. I regularly talk to my friend John, HK3C in Columbia at 5 watts and when conditions are awful I kick in a 50-watt amp that brings my signal right up with the big boys.
How can that be?
It’s because the actual difference between a station running 100 watts and one running 5 watts is only 2 S units. In other words if the 100-watt station is being received at S-9, the QRP signal will be heard at S-7 and if you didn’t look at the S-meter you’d not be able to tell the difference.
Running my 50-watt amp just brings my signal up a little wee bit – maybe an S unit or so.
BTW you can buy a really good QRP rig (HB1A – see above) for just over $200 new at Durham Radio. Add a Par end-feed QRP antenna and you’re on the air.