Not to take sides or anything, but I can understand why radio shops/techs can get a bit grumpy. I saw it a plenty of times during the CB craze when I did some installs for a radio shop. Guys would bring their CB sets in for repair and the shop owner would tell 'em, "Now don't mess with this: it's set right where it's supposed to be! Don't TOUCH that and keep your swizzle sticks OUT of your radio!!"
Sho 'nuff, they'd bring the radio back claiming that Jimmy (a real, degreed electronics guy with a 1st Class Phone required in those days) "messed up my radio") He did NO such thing!
"Uh, did you turn any pots?"
OH NO, I'd NEVER do that"
He was LYING thru his teeth. Techs can TELL if you have turned something, lie all you wanna!
But the prevailing idea was among untrained folks, all controls had to be to the far RIGHT! All pots had to be "tuned" so that the CBer saw
SOMETHING move on their cheap Dosy meter!
Yeah, sometimes Jimmy got a little "testy" with people because they wouldn't keep their fingers and screwdrivers OUT of the radios, then came blaming HIM when they smoked their rigs!
CWM