high swr problem need electronics wizard

[auspot]

the project that I'm building uses a glass tube running a cb radio with a linear.
I have a very hard time trying to get the swr down to 1.1 or even under 2. If an
antenna would work I would have no problem.

My question is can I put zener diodes after the antenna tuner to keep from
zapping the linear? Is so what size zener diodes would I need. approz 200 watts

Thanks for any help
auspot

 

[Captain Kilowatt]

the project that I'm building uses a glass tube running a cb radio with a linear.
I have a very hard time trying to get the swr down to 1.1 or even under 2. If an
antenna would work I would have no problem.

My question is can I put zener diodes after the antenna tuner to keep from
zapping the linear? Is so what size zener diodes would I need. approz 200 watts

Thanks for any help
auspot

Zener diodes?? :blink: After the antenna tuner?? You mean in line with the RF path in the coaxial line??

I have no idea why you would think about using zener between the tuner and amp or why you would think they would keep the amplifier from getting "zapped". Also not sure about the statement " If an antenna would work I would have no problem." You mean you are not using an antenna? Where is the tuner? Between the radio and the amp or between the amp and the antenna that you don't have?


Oh....and I may not be an electronics wizard but I did spend 22 years working in the engineering department of a commercial radio broadcasting company.

 

[w9cll]

Wow

 

[Robb]

 

[Beetle]

Tell us more about your "project" and your "linear".

Why 200 watts? Try using a dummy load instead of a radiating antenna if this is some sort of scholastic endeavor.

 

[Lil'Yeshua]

Standing Wave Ratio explained - YouTube

 

[Captain Kilowatt]

Tell us more about your "project" and your "linear".

Why 200 watts? Try using a dummy load instead of a radiating antenna if this is some sort of scholastic endeavor.

It would be even more of a scholastic endeavor if he didn't use one. Nothing quite like learning by trial and oops.

 

[auspot]

SWR problem

Its for medical use. You don't transmitt to someone. You use a signal general
to produce a square wave freq which goes threw a cb radio to a linear to a
antenna tuner to a balum to the sealed tube which emits radio waves.

check this out perhaps you will understand what I am trying to do.

CAFL - The Consolidated Annotated Frequency List

Was hoping that the zeners placed between the tuner and tube would stop the feed back of the freq so nothing will burn up.
Am I wrong in thinking this? :glare:

You use a zener diode between the solar panel and battery to keep the battery
from discharging to the solar panel.

auspot

do a google search for Dr Rife

 

[Grogan]

Speach. Less

 

[fodendaf]

Zener diodes are generally only used in dc circuits. The tuner alone is sufficient to protect the linear from reflected power, i.e. high swr. I can't imagine what you're trying to do doing anything more than giving you an rf burn but to each his own. Keep us in the loop because I for one am interested in the outcome of this project.
BTW, if you haven't seen it already check out the film napoleon dynamite. There is a scene in it with a homemade contraption that reminds me of you.

 

[AudioShockwav]

can I put zener diodes after the antenna tuner

No.

I have a very hard time trying to get the swr down to 1.1 or even under 2.

As has already been said, if you have an antenna tuner ( and it is capable of working properly at the power levels you are using ) you should be able to tune the antenna.
If the antenna is very poorly designed, you tuner may not be capable of the job.
You need to do some more study on RF/antennas/matching loads etc.


The reason we sound stunned by your question is that anyone around RF knows it is AC and any diode in series with the coax is a major mistake.

Something about a glass tube antenna is also a bit confusing, as glass is non conductive, therefore it can not radiate RF.

I did not read your complete list, just scanned through it, but I doubt you will find any "healing/treatment" frequencies in the 26.965-27.405 range.

I would not encourage anyone to expose themselves to high power RF at close range.


73
Jeff

 

[Beetle]

Its for medical use. You don't transmitt to someone. You use a signal general
to produce a square wave freq which goes threw a cb radio to a linear to a
antenna tuner to a balum to the sealed tube which emits radio waves.

check this out perhaps you will understand what I am trying to do.

CAFL - The Consolidated Annotated Frequency List

Was hoping that the zeners placed between the tuner and tube would stop the feed back of the freq so nothing will burn up.
Am I wrong in thinking this? :glare:
auspot
do a google search for Dr Rife

CAFL specifies "All frequencies in Hertz". You're gonna need a bigger "sealed tube which emits radio waves." Three Hertz? You do the math.

 

[Captain Kilowatt]

Speach. Less

Well that's more than I could come up with. :blink:

 

[auspot]

Captain Kilowatt

Did you read my last post? Do you understand what I am trying to do?
I was hoping the zeners would stop the feed back to give me time to get the
swr down under 2

auspot

 

[auspot]

The only thing I need to know is will the zeners work and how big or what capacity is needed.

Abdominal_inflammation - 2720, 2489, 2170, 2000, 1865, 1800,

the 2720 is 2 thousand 7 hundred and twenty or 2.72K or .00272 mhz, some people might think it is 2,720Khz or 2/720 mhz as this has to be programed into the signal general and being that high would
not help anything.

auspot