Sidebar Sidebar
  • You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
  • Click here to find out how to win free radios from Retevis!

Fine Tune CB

Status
Not open for further replies.
543_Dallas said:
I took mine around the first of the year. I haven't looked at a practice exam since the test changed a couple of months ago.
Click to expand...
Here's something you'll never learn on any of the test questions. All technicians in the country except for one subscribe to the theory that cable length means nothing on a test bench. All technicians in the country except for one subscribe to this Theory with nothing to validate it. One technician in this country uses a scientific formula to assemble his test equipment on his bench based upon scientific evidence that it matters which is displayed in this video.
 
rabbiporkchop said:
Here's something you'll never learn on any of the test questions. All technicians in the country except for one subscribe to the theory that cable length means nothing on a test bench. All technicians in the country except for one subscribe to this Theory with nothing to validate it. One technician in this country uses a scientific formula to assemble his test equipment on his bench based upon scientific evidence that it matters which is displayed in this video.
Click to expand...

And nearly all that theory was learned from Ham guys who are the majority if not all who wrote the books on this stuff long before CB's came along and long before we were born following in the tradition of Marconi.

Except for stub matching, you don't tune circuits with coax including antennas.

I can't believe Mark is the only CB tech who knows that or maybe I should say doesn't know.
 
Last edited:
  • Like
Reactions: Unit 194, darthanubis and Captain Kilowatt
rabbiporkchop said:
Here's something you'll never learn on any of the test questions. All technicians in the country except for one subscribe to the theory that cable length means nothing on a test bench. All technicians in the country except for one subscribe to this Theory with nothing to validate it. One technician in this country uses a scientific formula to assemble his test equipment on his bench based upon scientific evidence that it matters which is displayed in this video.
Click to expand...
The world's greatest CB/Electronics tech travels the country in his dilithium crystal powered mobile home saving the masses from the wrath of bad techs and evil hams. God bless this super human man and may his screwdriver and patch cables be made of gold. Long live this great man and may his trailer never have a flat. Travel safe oh Golden one travel safe..... damn good kool-aid...
 
  • Like
Reactions: Unit 194, Captain Kilowatt, dave457 and 3 others
:barefoot:I have heard Mark on the airwaves talk about using 1/2 wavelengths of coax to tune antennas. This also goes along with the common CB shop belief all coax cables must be in 3 ft. Increments.

So if I have a 1/2 way dipole antenna cut for 40 meters. The minimum ideal height above ground would be 66 ft. which is a half wave at that frequency. That means according to Mark, if use more than 66 ft. (1/2 wavelength)of coax up the tower, My antenna won't tune properly unless I put my radio directly at the base of the tower because I can't use any more to coax get inside my shack which would be at least another 25 ft.

Then again 11 meters has it's own theory that doesn't apply to Amatuer bands. CaptainKilowatt taught us that.:barefoot:
 
w9cll said:
The world's greatest CB/Electronics tech travels the country in his dilithium crystal powered mobile home saving the masses from the wrath of bad techs and evil hams. God bless this super human man and may his screwdriver and patch cables be made of gold. Long live this great man and may his trailer never have a flat. Travel safe oh Golden one travel safe..... damn good kool-aid...
Click to expand...
That's too funny!!! :D
 
fourstringburn said:
....

So if I have a 1/2 way dipole antenna cut for 40 meters. The minimum ideal height above ground would be 66 ft. which is a half wave at that frequency. That means according to Mark, if use more than 66 ft. (1/2 wavelength)of coax up the tower, My antenna won't tune properly unless I put my radio directly at the base of the tower because I can't use any more to coax get inside my shack which would be at least another 25 ft.

....
Click to expand...

Have you thought of using two 66ft coax's and a barrel connector.;)
 
rabbiporkchop said:
Here's something you'll never learn on any of the test questions. All technicians in the country except for one subscribe to the theory that cable length means nothing on a test bench. All technicians in the country except for one subscribe to this Theory with nothing to validate it. One technician in this country uses a scientific formula to assemble his test equipment on his bench based upon scientific evidence that it matters which is displayed in this video.
Click to expand...


Actually there are questions about the effects of different lengths of coax. 1/8, 1/4, 1/2 electrical wavelengths. Yes there is a formula...the formula is a different question.

I don't know why you keep posting these videos. Are you seriously trying to teach me something? Just to be clear, I do not believe that my ham ticket puts me above anyone who doesn't have one. I'll be the first to tell you that many hams are about as smart as you and Mark.
 
  • Like
Reactions: darthanubis
fourstringburn said:
:barefoot:I have heard Mark on the airwaves talk about using 1/2 wavelengths of coax to tune antennas. This also goes along with the common CB shop belief all coax cables must be in 3 ft. Increments.

So if I have a 1/2 way dipole antenna cut for 40 meters. The minimum ideal height above ground would be 66 ft. which is a half wave at that frequency. That means according to Mark, if use more than 66 ft. (1/2 wavelength)of coax up the tower, My antenna won't tune properly unless I put my radio directly at the base of the tower because I can't use any more to coax get inside my shack which would be at least another 25 ft.

Then again 11 meters has it's own theory that doesn't apply to Amatuer bands. CaptainKilowatt taught us that.:barefoot:
Click to expand...
Mobile and base applications are 2 different things
 
543_Dallas said:
Actually there are questions about the effects of different lengths of coax. 1/8, 1/4, 1/2 electrical wavelengths. Yes there is a formula...the formula is a different question.

I don't know why you keep posting these videos. Are you seriously trying to teach me something? Just to be clear, I do not believe that my ham ticket puts me above anyone who doesn't have one. I'll be the first to tell you that many hams are about as smart as you and Mark.
Click to expand...
Phase shift on an rf test bench alters the waveform on an oscilloscope.
Well intentioned adjustments based on faulty observations made on a misaligned bench result in less than stellar results.
A tech is only as good as the alignment of his bench. Most are incapable of duplicating a factory tune which is easily provable by making a side by side comparison with a stock radio.
 
Status
Not open for further replies.

dxChat
Help Users
  • No one is chatting at the moment.


      Top Bottom
      Back