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Question about a Bird 43A VS. 43P

I think what Doc is talking about in reference to a properly constructed AM signal is "normal" full carrier double sideband and not that crap that is so prevalent on 11m today. you know, 2 watts "swinging" to 35 watts. A normal AM signal would be about 8-9 watts of carrier and 100 % modulation for the exact same pep output however saying "swinging" 35 watts sounds SOOOOO much better than 9 watts carrier.

Are you sure about that.
I am asking him to explain how to use a BIRD 43 average responding meter to indicate PEP on a 100 % properly modulated carrier.
Specifically the standard issue AM mode as described by the emission standards of A3E double-sideband a full-carrier - the basic Amplitude modulation scheme.
He made the remark and now I want him to back it up.
Nothing wrong with that.
He keeps dodging it so I finally decided I needed to say: "PUT UP OR SHUT UP"
He has made a habit of posting in opposition to what I post and now I am tired of it and am gonna make a point to do the same thing to him.
He is the one that started out on this little campaign of his and now I am tired of it.
It all started after the thread: A SWR CONUNDRUM.

He needs to explain what he is talking about, if he does not then it is just an indication to me of who is trying to be the trouble maker.
I am not going to ignore someone when they post stuff that is bullshit and the only purpose is to oppose my post.
There needs to be a better bob85 bull shit meter in this fourm.
You got new people that are trying to learn stuff in this forum and you have people disseminating bullshit in here.
I think that is wrong.
 
OK.
But don't you think he needs to back up his remarks with the necessary correct information.
I think there are numerous people who would be interested in this.
I know the answer, I don't think I would rely on the method for accurate results.
It will get you in the ball park but if you are trying to properly modulate your AM carrier to 100 % then you either use a 'scope/monitor' or a quality PEP meter.
You don't use a average responding meter to generate PEP numbers without introducing an error factor of the magnitude 2.67 times the accuracy inherant to the meter being used.


Use a 'scope, as you said, or a GOOD modulation meter and by GOOD I mean lab quality not a CB type "mod meter". I use a Wavetek 4101 meter myself or a scope.

wavetek4101.jpg


Good read:

http://www.w8ji.com/amplitude_modulation.htm
 
To be truthful, I'm not interested in what my meter does for AM, I have an oscilloscope for that. I was curious about how a Bird 43A would read compared to a Bird 43P for SSB use, if they would have similar readings. I use a two tone audio generator for checking PEP output.



I wasn't meaning to have anyone get all wound up here... :unsure:



~Cheers~
 
To be truthful, I'm not interested in what my meter does for AM, I have an oscilloscope for that. I was curious about how a Bird 43A would read compared to a Bird 43P for SSB use, if they would have similar readings. I use a two tone audio generator for checking PEP output.



I wasn't meaning to have anyone get all wound up here... :unsure:



~Cheers~

According to W8JI average power of a two-tone test on SSB should be 1/2 the PEP.

If your meter cooperates with this formula then you have something useful here.
But like I said there is another way to measure PEP on SSB with a average meter and the only error is cause by the reduced power caused by the lowering of the supply voltage to the final section due to the large current demand associated with this method causing the power supply voltage to sag.
But do not try to use this method for AM.
 
I have my X-Force 2x4 base amp, and on my Bird 43A with a 1000W slug, it does 550W with a 2 tone audio tone. That's with about 4W reflected, for an SWR of about 1.1. I was curious to see if my PEP SSB output was around that number, or if it was any higher. Hence the question of a Bird 43A vs. a Bird 43P. :)


~Cheers~
 
There should be no noticeable difference in readings between average/Pep if you use a constant tone(s). Try it, see for your self.
- 'Doc
 
There should be no noticeable difference in readings between average/Pep if you use a constant tone(s). Try it, see for your self.
- 'Doc

This method will work good to determine the maximum output power of a SSB transmitter. The reason is when you put a constant tone into a SSB transmitter it simulates a full power carrier. However, it will not provide the same info with speech.
 

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