REDWING:
For the record, I don't operate a blacklist, just link to one. That's on someone elses website. I DO have the whitelist you talked about. I HAVE seen work from many of the shops on the blacklist, and I know why those shops are listed. EVERY shop on that site is there for one reason, namely that they cut or otherwise disable modulation limiters (R+R is one of those, I've seen dozens of their radios).
If you like a radio thats been clipped, thats fine. Many of us would rather have our radios TUNED rather than chopped, so I provide a list of shops who are known to TUNE, not chop. If havng that kind of list bothers you so much, it makes me think that you are one of the chop-lovers, and as I've said, thats fine. To each his own.
I've worked for a couple of the chop-shop type places, and I know most if not all of the little tricks that can be used to make some meter's needle move a bit further. Some are ok, but most comprimise both the audio and RF signal quality, many in the extreme. They don't yield any more power in the signal that you want. They just cause harmonic distortion in the audio signal due to clipping, plus harmonics and other out-of-band signals in the RF output for the same general reasons.
Most of the bleedover you hear comes from chopped radios, mainly due to the heavy harmonics in their audio. Those harmonics in the audio generate a much wider sideband signal, and that extra sideband content is way out of the 6-10khz channel boundary, which means someone else on an adjacent (or not-so-adjacent) channel has to put up with your crappy radio. If you run that extra sideband signal through an amp, well, you probably get the idea.
In case you're not aware of it, an AM signal consists of a carrier, and 2 other frequency components (sidebands), which consist of the sum (upper sideband) and difference (lower sideband) of the carrier and the modulation frequency. Most CB's don't employ much audio filtering to begin with, and the audio needs to be kept inside a range of roughly 100hz to 3khz to maintain channel integrity.
Audio harmonics are frequency components that are 2 times, 3 times, 4 times, etc the frequency of the main mic audio frequencies. In a clipped radio, due to the clipping (squaring-off) of the audio signal, most of the harmonics generated are odd harmonics. A square wave contains the fundamental frequency, plus alot of odd-numbered harmonics (3 times, 5 times, etc). A clipped radio's mic audio will contain MANY of those odd harmonics.
Imagine applying an audio signal that contains a 17th-order harmonic (present in any clipped radio) at fairly high level to the channel 19 carrier of a CB. 27,185,000 hz (ch 19 carrier freq), plus a frequency equalling 3khz (the highest audio freq that should be present) times 17 (51khz). That CB signal now occupies over 100khz of bandwidth, instead of the roughly 6khz it SHOULD occupy. Now you're bleeding over across at least 5 channels in each direction and generally more due to other types of RF distortion caused by a clipped audio signal. A 17th-order harmonic is generally not the highest harmonic generated, either. Taking the same idea, imagine now applying a 35th-order harmonic. That yields a signal bandwidth of about 210khz, about half the CB band. And clipped radios go even higher in harmonic content.
Why would you want a radio that generates useless signals on other channels, and thereby wastes alot of power in those signals? Why not set your radio up to concentrate its power in the signals you DO want? You'll have higher over-all power, not to mention modulation, in the channel you DO want, IF the radio is properly tuned.
Get the general idea? THAT'S why shops end up on that Blacklist.
NORTHSTAR:
Exactly my point!! A good, technically-accurate tune-up will ALWAYS give better long-term performance, as well as PROVEN better sound and signal quality. If you personally ran/run a CB shop, it would likely end up on that Whitelist.
