nd5y
Member
This guy mearsured the power output. Review 25W Leixen NOTE - Miklor
Brain tumor anyone?
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There is more to testing a transmitter than just connecting a wattmeter and a dummy load to see what the output is.
nd5y
Member
Did I say he completely tested everything?
Ah, interesting. It is hard to get a grasp of the scale of the size of the thing until you see the pictures of against some other popular radios.. It's very nearly double the size of the UV5R.
902
Member
Well, exactly. I wonder what this gem's spectral purity is. Had it been for other services, it would need to have been type accepted (not that type acceptance means much anymore in terms of noise), but these can be imported and sold without any of that.
I have to wonder whether flooding the market with under-priced and generally poorly designed equipment has been an attempt to destabilize our communications industry and systems.
Project25_MASTR
TX-COMU
I think it's been more to destabilize the communications industry with the Japanese (as some radios come off the same production line as their Japanese counter parts) who just so happen to do a lot of business around the world. The fact that it is affecting everyone is just an after-thought.
902
Member
You've got a valid point. I never considered it might be a very old grudge in play.
KK4JUG said:
The problem is that whatever ecosystem we had functioned on compliance. In this case, it's compliance with various regulations that were enacted as protection mechanisms so that we can all play in the sandbox together. In my view (and I don't want to get too political), China doesn't comply. Rather, it exploits the system by submitting samples for testing, but removing key components in production, or, in this case, not even considering SAR limits in producing their equipment. But I can also point to melamine adulteration in food products to falsely boost protein and lead-based paint on toys. One might argue "Aww, they didn't know better." On one side of the continuum, maybe not. On the other side, they probably did. It's hard to pick.
In terms of how cheap imports affect the marketplace, you also have dealers who insured a level of operational integrity and contributed value-added services to insure users went... down the right path. We have many local shops closing because the better quality products they sell are much higher cost than the inferior quality items available mail order. Likewise, we've also gone "free range" in terms of how some users implement their devices. In the last few days, I've read about (US) hotels on 400 MHz, kids talking on police frequencies, and a bunch of other items that seem to be happening with greater frequency. Would a responsible communications dealer hand something out that would harm their reputation and the community they do business in?
My old /\/\ Saber III VHF was good for 7 watts.
Going back to the OP, I learned elsewhere that the Biophone used in the show "Emergency" was supposed to put out 50 watts on UHF.
Who needs a defibrillator when all Johnny Gage would have to do is key that sucker up next to the heart attack victim!
Project25_MASTR
TX-COMU
My old /\/\ Saber III VHF was good for 7 watts.
Going back to the OP, I learned elsewhere that the Biophone used in the show "Emergency" was supposed to put out 50 watts on UHF.
Who needs a defibrillator when all Johnny Gage would have to do is key that sucker up next to the heart attack victim!
Last time I threw my Astro Saber III on a system monitor is read 5.5W on 146.520. Not wanting to break out the tuner software and mess with it I just left it as is.
prcguy
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I worked on Biophones in the 1980s and although I forgot their power level, it was nowhere near 50w.
prcguy
prcguy
My old /\/\ Saber III VHF was good for 7 watts.
Going back to the OP, I learned elsewhere that the Biophone used in the show "Emergency" was supposed to put out 50 watts on UHF.
Who needs a defibrillator when all Johnny Gage would have to do is key that sucker up next to the heart attack victim!
Project25_MASTR
TX-COMU
Most of my microwave links put out between 22 and 27 dBm on 5 GHz…add in 22 dBi and 30 dBi gain dishes and we are just getting warmed up (pun intended).
I and others here at the shop think this guy must have missed all the questions on his HAM test about RF Exposure.
When I last looked,US market handheld radios had a safety limit of 7 watts output. I don't think that 25 watts poses that big of a health issue, though I wouldn't like to have it radiated centimeters from my head.
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What struck me more is---> to what advantage is 25 watts over, say 5-7 Watts? The human ear, and its associated brain (if it hasn't been fried... ), can just detect the difference in a 2 "S" unit signal change. Assuming the radio industry's unofficial standard for an "S" unit as ~6Bdbs., that would mean you have to increase the power over 7 watts to over 100 watts to notice a difference. Now that would be some awesome handheld, and probably get a health issue ban.
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I think I'd save my money.
.....................................................CF
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What struck me more is---> to what advantage is 25 watts over, say 5-7 Watts? The human ear, and its associated brain (if it hasn't been fried...
), can just detect the difference in a 2 "S" unit signal change. Assuming the radio industry's unofficial standard for an "S" unit as ~6Bdbs., that would mean you have to increase the power over 7 watts to over 100 watts to notice a difference. Now that would be some awesome handheld, and probably get a health issue ban..
I think I'd save my money.
.....................................................CF
The human ear, and its associated brain (if it hasn't been fried...
Well, to start with an S unit is 6db and the normal "just easily audible" change for the human brain is 3db, half an S unit NOT two. Two S units would be 12db and 10db sounds "twice as loud" to the average ear.
So you just have the numbers entirely wrong so far as the human ear/brain is concerned.
And then we aren't just dealing with the human ear/brain, we are dealing with a *radio* that is typically a whole lot more sensitive and can far resolve better than the human ear/brain combo. Even 1db can, especially on FM due to the capture effect, make the difference between uncopyable and fully copyable if a bit noisy.
On HF one S unit usually doesn't mean much, but two S units generally make a big difference so far a being able to talk on SSB is concerned. An S unit on CW can make a big difference.
Project25_MASTR
TX-COMU
Difference between 100W and 10W less than 2 S units.
Sometimes I like to push power (like the fact low power for my VHF rig is 50W) but usually for tropo to fight ground attenuation. On UHF I usually run 10-20W on a mobile with a quarter wave antenna. I've never noticed a need for anything higher usually as its predominantly LOS.
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I do agree, that this was an over simplification of a hypothetical radio scenario. But I will maintain that the average person can not tell the difference between a S7 and an S9 signal, as registered on their FM radio's S-Meter... and we are talking about a 12 db increase in RF power, not necessarily a 12 db increase in audio out of the speaker.
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I guess I live and work in a different world. Ham radio operators, by and large, seem to develope very keen ears for pulling meaning out of the ether. In my field, we consider a transmitted signal of 12DB's increase in RF power to be the general break over point for a (non-ham) ear to detect the *noticeable* difference on their receivers. There are, of course, a myriad of exceptions to this (ie; the agc settings, is this a SDR receiver?-etc) and as stated, an experienced operator can pull meaning out of what is simply noise to the average ear.
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I am sure you all have done it, but those that haven't- try this the next time if you can, - reduce your transmit power during a conversation from, say 80 watts to 10 Watts (9 Dbs).....FM..... with signals at S9 at first...and don't tell the other station what you did... see if they noticed "anything." Since we are dealing with a biological entity- a very analog entity, the human ear-- and not simply an S-meter, I would be surprised if they do notice a difference. Of course if the signal is marginal, and the there is poor 'capture,' etc.,the experiment will turn out different.... and you hams, remember that you have a highly trained ear- get a non amateur to listen.
.
All in all, I don't think there is any thing gained, signal quality-wise by going to 25 watts on a handheld -- which was the subject of the original Post.......
;
.............................................CF
.
I guess I live and work in a different world. Ham radio operators, by and large, seem to develope very keen ears for pulling meaning out of the ether. In my field, we consider a transmitted signal of 12DB's increase in RF power to be the general break over point for a (non-ham) ear to detect the *noticeable* difference on their receivers. There are, of course, a myriad of exceptions to this (ie; the agc settings, is this a SDR receiver?-etc) and as stated, an experienced operator can pull meaning out of what is simply noise to the average ear.
.
I am sure you all have done it, but those that haven't- try this the next time if you can, - reduce your transmit power during a conversation from, say 80 watts to 10 Watts (9 Dbs).....FM..... with signals at S9 at first...and don't tell the other station what you did... see if they noticed "anything." Since we are dealing with a biological entity- a very analog entity, the human ear-- and not simply an S-meter, I would be surprised if they do notice a difference. Of course if the signal is marginal, and the there is poor 'capture,' etc.,the experiment will turn out different.... and you hams, remember that you have a highly trained ear- get a non amateur to listen.
.
All in all, I don't think there is any thing gained, signal quality-wise by going to 25 watts on a handheld -- which was the subject of the original Post.......
;
.............................................CF
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prcguy
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The difference between an S7 and S9 signal on an FM receiver should not be detectable because most any FM receiver should be in full limiting and the signal would be already be full quieting at S7. On a noisy signal, two S units or 12dB will be a very noticeable change that anyone will hear.
If your weak but barely readable in FM mode and you drop 12dB in signal level you would not be readable at all. If you go from weak but readable and add 12 dB it will be a fairly good signal with little noise depending on the receivers limiter. When aligning FM radios, a 3dB change in signal level is very noticeable to me. When doing audio measurements and adjustments, I can hear a 1dB change in a cross over on a speaker system, so small changes are noticeable.
prcguy
If your weak but barely readable in FM mode and you drop 12dB in signal level you would not be readable at all. If you go from weak but readable and add 12 dB it will be a fairly good signal with little noise depending on the receivers limiter. When aligning FM radios, a 3dB change in signal level is very noticeable to me. When doing audio measurements and adjustments, I can hear a 1dB change in a cross over on a speaker system, so small changes are noticeable.
prcguy
I do agree, that this was an over simplification of a hypothetical radio scenario. But I will maintain that the average person can not tell the difference between a S7 and an S9 signal, as registered on their FM radio's S-Meter... and we are talking about a 12 db increase in RF power, not necessarily a 12 db increase in audio out of the speaker.
.
I guess I live and work in a different world. Ham radio operators, by and large, seem to develope very keen ears for pulling meaning out of the ether. In my field, we consider a transmitted signal of 12DB's increase in RF power to be the general break over point for a (non-ham) ear to detect the *noticeable* difference on their receivers. There are, of course, a myriad of exceptions to this (ie; the agc settings, is this a SDR receiver?-etc) and as stated, an experienced operator can pull meaning out of what is simply noise to the average ear.
.
I am sure you all have done it, but those that haven't- try this the next time if you can, - reduce your transmit power during a conversation from, say 80 watts to 10 Watts (9 Dbs).....FM..... with signals at S9 at first...and don't tell the other station what you did... see if they noticed "anything." Since we are dealing with a biological entity- a very analog entity, the human ear-- and not simply an S-meter, I would be surprised if they do notice a difference. Of course if the signal is marginal, and the there is poor 'capture,' etc.,the experiment will turn out different.... and you hams, remember that you have a highly trained ear- get a non amateur to listen.
.
All in all, I don't think there is any thing gained, signal quality-wise by going to 25 watts on a handheld -- which was the subject of the original Post.......
;
.............................................CF
Last edited:
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