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XLAXX
| | Posted on Monday, October 07, 2002 - 12:26 pm: | 
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I realize that whistling over the airwaves is FCC illegal, but not into a dummy load for testing. Is whistling a true or good indicator of how well a radio will swing forward?
When a person says AAAUUUDDDIIIOO into the mic, there seems to be less swing than when one whistles.
Just wondering and curious because many do it.
Thanks
XLAXX |
VisitTennguy
| | Posted on Monday, October 07, 2002 - 2:33 pm: |
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NEVER whistle in to a radio, when you do all you are seeing is one tone!! saying AUDIO is much better because it is a true indicator of your voice quality!! |
Taz
| | Posted on Monday, October 07, 2002 - 8:39 pm: |
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Yeah, dont whistle to take wattage reagings!!!
It dosent count. Do you talk by wistling?
Tennguy is right, you want to inject a tone around 400hz I beleive. When testing output try saying words like truck cut crash and kite. The
"cuh" sounds make good swings. |
Deadly Eyes
| | Posted on Monday, October 07, 2002 - 10:05 pm: |
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The best way to determine mike gain is to simply count to ten in your normal voice with the mike the normal distance from your mouth as you would doing a regular conversation. Speak in a normal voice at normal volume. |
HoosierCardinal
| | Posted on Tuesday, October 08, 2002 - 1:06 pm: |
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Just say AHHHHHHHHHHHHH!
It will give a true reading versus whisting... |
bullet/151 southern Indiana
| | Posted on Thursday, October 10, 2002 - 2:29 am: |
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"the quick brown fox jumps over the lazy dog"....
takes me back to my fort gordon signal corp days |
HoosierCardinal
| | Posted on Sunday, October 13, 2002 - 12:37 am: |
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heres a goodie!
I used to know a guy that worked on CB radios that get this, used a coaches whistle to tune up radios!!!! I saw that and i about died!!!! |
ss8541
| | Posted on Sunday, October 13, 2002 - 1:08 am: |
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a whistle will work fine(not a coaches whistle). if it is good and steady it will work fine. it is a single tone and what you want. read any service manual they ask for a 1khz tone, most human whistles are around 1.3khz. the tone frequency isn't so important. your voice and a whistle modulates the rf to the EXACT same level. the difference is that voice is a complex rf form that gives a meter a hard time(and why service info says to use a single 1khz tone). -but- when using a scope or spec-an you will see that voice and a whistle will reach the same peaks that are not seen on a meter(yes i have tested this, so i am positive this is the case). so when using a meter, a whistle is the best way to get a good idea of what your peak rf power(peak here is relative to the meter you are using) is when voice modulation will be added. your voice will be hitting the same peaks as the the whistle did(even if the meter isn't showing it). |
ChillyDog
| | Posted on Monday, October 14, 2002 - 10:19 am: |
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ss8541,
As always, I agree with you 100%. If you don't have access to an audio generator, a steady whistle is great for evaluating peak output.
For optimal SSB adjustments, a dual audio tone is necessary, but you can do almost everything else with a whistle!
Incidently, a coach's whistle doesn't generate a steady tone because the little ball rotating in it modulates the higher frequency whistle sound. I wonder how it would be if that ball were removed?
Best Regards,
Bob |
Taz
| | Posted on Monday, October 14, 2002 - 11:40 am: |
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download a tone generator. inject a tone closest to your voice.
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ss8541
| | Posted on Monday, October 14, 2002 - 11:48 pm: |
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hey you cold s.o.b.(chillydog), thanks.
and taz on average the male voice is centered around 1khz. also, this is the area that the audio response peaks for most radios mic circuits. 2 reasons to use 1khz. |
HoosierCardinal
| | Posted on Tuesday, October 15, 2002 - 5:40 pm: |
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Well i forgot to ad that he had the little rubber ball removed so it would be a steady tone instead of a waivering whistle... I guess whatever works! |
jyd
| | Posted on Tuesday, October 15, 2002 - 7:27 pm: |
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all my old books say to say heellllllo,instead of audio.old school books.just thought i would throw that in.not trying to step on toes,it work better i think.my opinion |
ss8541
| | Posted on Tuesday, October 15, 2002 - 8:38 pm: |
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any book that says to say hello, audio, or anything else would be more useful as a roll hanging in your bathroom than for anything else. |
307
| | Posted on Tuesday, October 15, 2002 - 10:23 pm: |
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Here is a free tone generator for use in exactly what you need...
http://www.nch.com.au/tonegen/index.html#104
As for the "any book that says to say hello, audio, or anything else would be more useful as a roll hanging in your bathroom than for anything else."..
He who has NEVER said "audio" , "whistle'd" or said "hellllllllo" into a microphone before for a power measurement is being less than honest. :-)
307
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ss8541
| | Posted on Wednesday, October 16, 2002 - 12:28 am: |
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maybe you should re-read this 307 as 2 of us stated that a whistle is fine for checking peak power, and gave facts to back it up.
but hello, audio, big radio, mud duck, or any other word is not fine for testing peak rf power at full modulation for the reasons listed above(unless you have a scope or spec-an with max peak hold or a good eye).
the orginal question asked about a whistle and saying audio, and the obvious difference in -DISPLAYED- power. it also asked if a whistle was a good indication of peak power. i answered this by showing the difference between the two, and supported it with facts.
i didn't mean to offend anyone. i was only teaching correct rf testing procedures. if you don't have a af gen, use the next best thing, the whistle god gave you(not that this is 'proper' by the standards, but it will give the same results).
he who writes that saying any word is the proper way to check peak modulated power on a wattmeter is being less than honest with his readers. ancient 8541 proverb. |
fader
| | Posted on Wednesday, October 16, 2002 - 10:21 am: |
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I believe what 307 is saying is that whistling isn't really "proper" either. The only thing you have shown evidence of is that in your one person experiment your whistle works better than your voice. Neither way will generate a steady tone but lacking the proper equipment it will do. Which method is better I believe will depend on the individuals ability to whistle or to hold a steady tone while saying a word. |
ss8541
| | Posted on Wednesday, October 16, 2002 - 10:31 pm: |
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show me ones persons voice that will modulate a cb type wattmeter to the same level as their whistle, and i'll shake your hand. but watch any form of a am modulated carrier(whistle, voice, or tone from an af gen) on a scope or spec-an and you will see that they all give the exact same rf level. so if they are all doing the same on those, and a whistle or tone from af gen, is giving a certain reading on a meter, guess what???, your voice is also even though the meter isn't showing it(due to its complex waveform). so why not use a whistle on the meter to begin with if that is what gives the same indication of peak power as an af gen when using a cb type wattmeter? try it sometime fader(if you have access to a scope and af gen, i know you can whistle). if you don't have access to this, and haven't done the tests, then you really can't say what i have or haven't proved.
since several others noted that their whistle 'registered' higher than their voice, it sounds like more than a 'one person experiment'. i just gave the facts as to why this happened/s, to the 'many person' experiment. my credentials have spoken across a few forums. those who know me know that i am devoted to rf work. i only teach correct rf principles, and that is one reason i posted to this topic(i saw some cb myths).
i am not here to advertise my services. i have never told anyone here to 'email me' or emailed anyone on this site to draw customers. those who wish for my services know where i am at(and they find me). i am here because copper honestly has the largest amount of active members in its forum. what better place to aid in the learning of operators as to what is 'correctly' going on inside their systems, and the 'correct' ways to test sytems and what those test results mean than a forum like coppers.
i am also not here to make anyone else look bad. but if i see something that isn't right, i'll point it out and correct that statemtent. and if someone sees something that i say, and it isn't right i'll back down if the proof to support their statements is brought forward. i don't believe in the 'its right because i say so' b.s. that is why you usually see me take the time to explain where i am coming from, like it did here from post #1. |
jyd
| | Posted on Wednesday, October 16, 2002 - 11:18 pm: |
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people never seese to amaze me,i just through that in for the hell of it.now i know not to throw my or someone elses opion in.why does everything have to be a argument.ss is rude!i will remember not to post where he does.i am not going to say anything else.mama siad if you cant say nothing nice dont say anything at all! |
fader
| | Posted on Wednesday, October 16, 2002 - 11:41 pm: |
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ss8541,
Your evidence consist of anecdotal quotes("since several others noted that their whistle 'registered' higher than their voice") and your personal one person test.
Then you offer your credentials("my credentials have spoken across a few forums") and your devotion to the hobby("those who know me know that i am devoted to rf work") as evidence that your proposition is valid.
You present yourself as someone who is grounded in scientific fact but then proceed to advance your "fact" using unsound scientific principles. I can find the same level of proof that an idea is valid on the late night infomercials.
Does this sound familiar?
Anecdotal Testimonials : Uncle Jim and his whole family use it and love it. It works for them and it will work for you.
Unsound Scientific Proof : Bob is a mechanic and he uses it. Ask Uncle Jim and his family and they'll tell you Bob is a great mechanic.
Your methods are exactly how the very myths that you want to stop get started.
If you had presented your idea as "this is what I have found works" and not as proven fact I wouldn't have challenged it but alas you didn't.
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Tech671
| | Posted on Thursday, October 17, 2002 - 5:48 am: |
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No scientific facts here, but this is what I have found over the years. In my early CB days I tuned by a whistle. As time went on and I experimented more, I found that when I tuned by whistle my avg talking wattage was lower than had I tuned by "aaauuuuuu" or voice. Watching the wattage as I carry on a normal conversation, a radio tuned by voice was about 10-15% more power than had I tuned by whistle then read avg conversation wattage.
No flames, no dispute, just my opinion. and it looks good on my scope (Bushnell). Haha...joke. |
jyd
| | Posted on Thursday, October 17, 2002 - 9:36 am: |
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true,671 |
ChillyDog
| | Posted on Thursday, October 17, 2002 - 10:43 am: |
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It's too bad that dissention comes with disagreement! It'd be great if we could disagree without taking things personally. And before anyone thinks that I am directing the above comment to them, please be assured that I am speaking in general terms and am not refering to any individual. That said, I'll jump into the frey and add my perspective to this debate ...
When adjusting or measuring the peak output (note that I'm discussing _peak_ output) of a radio or RF amplifier, a steady modulated signal must be used. Additionally, an accurate means of measuring not only the numerical results of the output, but also the quality of the signal.
For someone with access to and training on the correct equipment, an audio generator along with an oscilloscope is the minimum equipment needed to correctly measure or set peak RF output. Use of a spectrum analyzer allows optimization of the signal quality. Most contibutors to this forum never get an opportuinity to use that type of equipment. (I sure wish I still had access to a spectrum analyzer ...)
Because most people use inexpensive power meters and their own voice to make adjustments, certain "CB myths" and work-around practices have come about.
One of these myths is that saying certain words or phrases is the correct way to measure peak output. From a strictly technical perspective, that is incorrect. However, for practical purposes, given the limited equipment available to many users, it's not _wrong_ to say "audio" or "test" or "hello" or whatever when trying to evaluate the performance of a radio or amp. It is _not_ however, measuring peak power by strict definition. What using anything other than a steady tone measures is more of measuring average power output rather than peak. This can be a practical measurement, but it's not a precise one.
Still, it's better than just slapping an amp on a radio without any attempt at all to adjust for correct drive level. If using a variable signal ("audio," "hello," etc.) to adjust output is followed buy on-air checks for transmission quality, both on-channel and off, a reasonable adjustment can (but may not!) be made.
Using a whistle as opposed to voice peaks reduces the chance of overdriving an amp during voice transmission. Without an oscilloscope, however, measuring peak levels is an approximate deal.
I strongly encourage anyone who has never seen a radio output on an oscilloscope to find the opportunity to do so. Find a person with a scope or pay a good CB shop's bench fee and have the tech demonstrate exactly what a properly adjusted output looks like. Have him inject a pure tone, a whistle, and some audio modulation and look at the difference. While transmitting into a dummy load, go ahead and overmodulate; see what it looks like. The education you'll receive in 15 minutes is well worth $25 or so.
Very Best Regards,
Bob |
Taz
| | Posted on Thursday, October 17, 2002 - 10:45 am: |
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thats funny cause they make telescopes and binoculars (bad spelling) |
Insider
| | Posted on Thursday, October 17, 2002 - 3:31 pm: |
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Personal experience here...
My whistle isn't that loud. When setting modulation levels, I prefer to use a steady hum, followed by talking in my normal speaking voice and comparing the readings.
Then again, I don't set mic gain for max wattage, but rather modulation and audio quality without going over 100%. Okay, sometimes I get a bit louder in conversation and it dips over--I watch that meter a lot.
I'm not really a big peak power freak as our brain doesn't turn peak power information into perception (high school and college Biology, and Recording Fundimentals).
I'm always looking for ways to keep my average level up: such as voice inflection/intonation and once I get the Kenwood set up again, I'm going to experiment with a dbx compressor.
I've also found that tuning a tube amp with just the carrier produced no different results than tuning using a ssshhh as some of the folks in my area like to use.
And I've proved nothing other than I still remeber parenthetical notation. He, he, he... |
jyd
| | Posted on Thursday, October 17, 2002 - 5:43 pm: |
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it really dont matter guys bad spelling,audio,whistle,boo,baaahh,i just through my post in for the fun of it.everyone does it their own way.but when using a scope you want rounded waves and it is hard to get them from a whistle unless you turn the mike gain way down.then so so,but how many of us has a scope? i agree with 671 onn his post,but antway wer all here to have a good time and help each other and enjoy our selves at the same time.good day boys |
Insider
| | Posted on Thursday, October 17, 2002 - 7:43 pm: |
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agreed jyd... |
HoosierCardinal
| | Posted on Friday, October 18, 2002 - 12:29 am: |
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I use a whistle ( the one god gave me) and it works for me. Ive said it before and i will say it again. "whatever works for the induvidual".... |
Scrapiron63
| | Posted on Friday, October 18, 2002 - 10:01 am: |
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Years ago Copper sold a little tone generator, cheap in price but worked well. Anything that produces a study tone will work when tuning a radio or tunable amp, at least well enough for most CB'ers, maybe not for these scientific folks. A peak is a peak, however a series of words or a two syllable word won't work, as you will have up and down peaks while your trying to adjust. Ahhhhhhhhhhh works well and a low steady whistle is great for most radios, but I have tuned some that would not respond to a whistle, not on my meters anyway, but would show forward with ahhhhhh. Heck, I've known people to use a hair dryer, that study hum does pretty good. Of course you don't need to direct the heat into the mike, unless it's REALLY cold. lol |
XLAXX
| | Posted on Friday, October 18, 2002 - 12:19 pm: |
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Appreciate the replies to this post!
Apologies for some of the flames going on in this thread.
I have been told that holding a keyed mic to a speaker telephone dial-tone is also useful for wattage and modulation readings?.?.?.?
When I whistle and increase the pitch (higher tone) of it, my wattage readings increase. This is not a continuous tone, however.
XLAXX |
HoosierCardinal
| | Posted on Friday, October 18, 2002 - 7:58 pm: |
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I say who cares its just CB! Some guys take this stuff way to seriously! Me im never seious about alot of this stuff. As long as it does the job thats all that matters i say!! |
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