Yeah we all understand the reasoning. The problem is the idiots who dont understand what they are using. To them its just a cheap amplifier.
The bottom line is that we need enforced commercial ITU mandated IMD standard forced onto the ham radio market because of the lack of technical ability of new hams. You or I could fix the bias problem on a CB amp. The problem is that you have hams who dont know how to solder on a PL259 or even solder a simple audio patch cable. How can you expect them to even come to understand what IMD is or how to fix it. When you dont have the brains to know that your illegal CB radio sold for ham purposes has a crap receiver and a equally poor transmitter, how can you even expect these types of hams to be considerate to other users of the ham bands?
We just have to face the fact that many new hams are no smarter than the dumb blonde who uses a cell phone and will never ever have any technical understanding of the technology that they using. With this level of expertise we need rules that govern what equipment they use and how they use it. Having mandated technical standards like the HF marine and other radio services is the way to fix the problem of dumb hams. I never thought I would use the the words dumb and ham in the same sentence, but here we are today. If you need your evidence listen to the PT0S pileups, the IMD and crud is bordering on obscene and many of those signals come from CB amplifiers.
It does not matter how logical your arguments are, these CB amps dont belong on the ham bands and new hams need to get this message. You cant negotiate your way through problem this with sensible arguments, you dealing with idiot end users who treats the ham radio hobby as his or her personal property to do as they see fit. Its just unfortunate that these dummies choose CB amplifiers and have no appreciation
for the technical reasons why doing what they doing is wrong and inconsiderate. Its wrong and inconsiderate, end of argument. No different to the ESSB users who are inconsiderate and selfish users of the ham bands for no real improvement in science, its all about looking good and having a ego. If that includes taking out 15 khz of the band thats OK for these types of people. We live in a society where individuals deem that their personal freedom is more important than the greater community and if you dont like the smell tough luck, ham radio is no different. CB amp users on the ham bands are IDIOTS, end of story.
quote author=ZENKI link=topic=86252.msg633814#msg633814 date=1353054675]
All really poor CB rubbish that does not belong on the ham bands.
Why any ham would want to use this CB garbage on the ham bands in the form of splattering CB amplifiers and freeband CB radios with poor IMD suppression is beyond belief. There are so many affordable genuine ham radios
available that perform much better and cost less. A second point is that the economics of buying a freeband radio and crap CB amplifier dont add up when you can buy a proper 100 watt transceiver like the IC718 for much less money.
The operating ergonomics is certainly superior. I guess you cant take the CB'er out of some hams. It seems many CB'ers who become hams dont want to give up their ignorant ways and poor equipment.
Leave the CB junk up on the CB bands not on the ham bands.
Hams who use this type equipment stand out like sore thumb on the ham bands because of the interference that they cause. It seems many hams who use this equipment suffer from technical deficit disorder, it seems that there is no cure for this malaise.
You need to understand the purpose of each equipment first, then start calling it "junk" or otherwise. A transmitter made to run on mobile, on a monoband resonant antenna and with 10KHz spacing between channels won't be as clean in IMD and harmonics as a transmitter made for the ham bands, of course; that doesn't mean it's junk, just that it was made for another purpose, where it may do it's job very well. Also, the CB mobile amplifiers are running in class-C because they're made for FM, and certain designs can meet ERP harmonics requirements even without amplifier output filters; the equipment is not necessarily junk, it's designed for another purpose.
The person that uses such equipment in another way that it was intended to, well, that is the real problem. A "500W" CB amplifier usually uses a pair of transistors that can actually put out less than 300W in total, and to be SSB IMD compliant you need to modify it to class AB and run it at below 200W out. It's specs will stand up to any decent ham amplifier this way, but it makes no sense in getting such a thing as long as you already have reasonably priced ham transcievers out there that put out 100W.
@ Mark W8GU: from 25W to 100W you have a 6dB increase, that is a single S-unit at the recieving station. In my opinion it's not worth it to go trough the trouble for only that much; you would first need to go for the best antenna you can use, than start thinking about more power - and when you do, go for something around 300W, otherwise you won't even notice the improvement. Plus there is the problem of not overdriving the amplifier, usually amps have around 10-13dB gain (5-10W input > 100W output), if you want to drive a 100W amplifier with 25W you'll have to either add an attenuator (one that can handle 25W will get hot, needs a radiator, box and RX/TX switch of it's own, adds to the price) or turn down the transciever output power, wich may kill the amplifier by overdriving if you accidentally forget to turn it down everytime you switch the amp on, or the transciever may spike on TX (ouputs max power for a very short time even if power it's turned down).