Oscilloscope

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digitalanalog

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None of my scanners have an S-meter, so i am looking to get a OSCILLOSCOPE to check signal strength(s)

any particular Make,Model or specific things to look for when choosing one?

Thanks in advance.
 

digitalanalog

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As i very much appreciate your response.
I really don't want to get into taking all my scanners apart to test signal strength on each one

An oscilloscope or as "mancow" mentioned a spectrum analyzer with test without having to open each scanner and make a seperate reading on each one.

As originally posted and help on Make,Model or other things to look for would be greatly apprecaited, maybe even one currently available on eBay would help.

Thanks.
 

Don_Burke

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As i very much appreciate your response.
I really don't want to get into taking all my scanners apart to test signal strength on each one

An oscilloscope or as "mancow" mentioned a spectrum analyzer with test without having to open each scanner and make a seperate reading on each one.

As originally posted and help on Make,Model or other things to look for would be greatly apprecaited, maybe even one currently available on eBay would help.

Thanks.
As posted by mancow, an oscilloscope is not going to get it done.

In any case, you would have to hook it onto the scanner _somehow_ and that would involve going inside the scanner.

Why would you need a signal strength from each scanner? Having one with a signal strength indication would be handy for antenna comparisons and antenna aiming, but that would be about it. At VHF and above, signal strength is not all that important.
 

davidbond21

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A cursory glance on google tells me that you may probably end up paying less for a scanner with an S-meter than you will for a spectrum analyzer anyway.
 

digitalanalog

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As posted by mancow, an oscilloscope is not going to get it done.

In any case, you would have to hook it onto the scanner _somehow_ and that would involve going inside the scanner.

Why would you need a signal strength from each scanner? Having one with a signal strength indication would be handy for antenna comparisons and antenna aiming, but that would be about it. At VHF and above, signal strength is not all that important.
Every scanner reacts differently to every antenna.
I have found this out with my many home brews as well as factory antenna's.

So i am just looking to fine tune what antenna's work best and what freq's and what scanners receive
better on what antenna's.

Test and tune as it's been called before.

Fine tuning a scanner to a antenna is the same as many many ham users do for their hobby as well
as they spend hours and hours and big bucks some times to achieve the ultimate combination.

I just want to be able to see what my antennas are doing as far as receive goes.
and i have been told the RIGHT sillyscope will do the job, i was not told what sillyscope to use to see what i want to see, that's why i made this post.

Thanks again for your input i do appreciate it.
 

zz0468

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This is clearly one of those cases where the lack of fundamental knowledge would render any test results useless. I don't intend that as an insult. I do intend that in a manner that would save you lots of time, trouble, and money, if only you would open up to what people are telling you. More below...

Every scanner reacts differently to every antenna.
I have found this out with my many home brews as well as factory antenna's.

So i am just looking to fine tune what antenna's work best and what freq's and what scanners receive better on what antenna's.

Test and tune as it's been called before.
I think you're misinterpreting some of your results, and in either case, a great deal more test equipment would be required to see if/how any particular antenna reacts differently to different receivers. Relative signal strength is not necessarily a good measure of how well a receiver or antenna is functioning. And any difference of how a particular receiver reacts to a particular antenna is highly unlikely to show itself in the form of an s meter reading. Low band reception on an 800 MHz antenna is going to stink, no matter what receiver you use. 800 MHz reception on that same 800 MHz antenna is going to show identical relative signal strength characteristics, regardless of which receiver you use, meaning what peaks it in one receiver, will peak it in another. A relative signal strength reading will show gain improvements on an antenna, but it would be a pointless exercise to make that measurement with every receiver you have. The results would be the same.

Fine tuning a scanner to a antenna is the same as many many ham users do for their hobby as well as they spend hours and hours and big bucks some times to achieve the ultimate combination.
What is it you hope to adjust? The scanner, or the antenna? Scanners generally are going to have a broad band input stage that's not adjustable. You get what you get. A realistic difference to expect between different makes and models of scanners would be noise figure, as a function of frequency. Some scanners amy perform better at low band, for example, than another. A different scanner may perform better at 800. But this is nothing you can fix or adjust without a preamp. I would also add that optimum noise figure doesn't necessarily come with best match to the coax, or with highest gain i.e. strongest signal levels. But it IS the only thing that really matters in weak signal reception.



I just want to be able to see what my antennas are doing as far as receive goes.
and i have been told the RIGHT sillyscope will do the job, i was not told what sillyscope to use to see what i want to see, that's why i made this post.
Well, you were told wrong. An oscilloscope is SO not the right instrument to use. As suggested, a spectrum analyzer would do the job of measuring signal strength, but then, it's a stand alone instrument, and wouldn't make any distinction between receivers.

What you need is an antenna test range with a calibrated signal source, and a means of measuring antenna gain and signal to noise ratio across the test range. You also need a noise figure meter, and a calibrated noise source.

Or, you could settle on something that makes sense, like a meter that monitors AGC voltage on a receiver, and base your antenna experiments on that. But you've already discounted that idea, so I doubt we can help you.
 
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tactcom42

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My scanners dont have s-meters.So I built one useing an old cb meter.you can go to the link below and read about adding a signal meter.Works great on my pro-2042 and it sure isnt digital!!!! Just take's a couple parts and away you go.works great for testing homebrew yagi's




http://www.mikedunton.com/tech/2003/2003_rs-meter.html
 

k9rzz

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If the signal has no noise, does it really matter how strong it is? If it does have noise, BINGO! adjust to minimize it. Otherwise pick up a receiver that does have an S meter, that would probably be the easiest way.

My .02 and probably worth less.
 

loumaag

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As k9rzz points out above, your ear will suffice for what you are looking to do. Now if you are just looking for a project, you are going to have to get over the trepidation to opening up your radio. :wink:
 

digitalanalog

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I will conduct my testing as Originally planned
with a Sillyscope, I have spoken to some
RF experts from several different companies
IE, Digital Sat as well as Broadband and
I have found the the type of scope needed.

And it CAN be done with a scope, as i knew
or why would i have asked.

I asked for help on what scope was needed
and no one could provide this information.

I was not looking for opinions.

I was looking for particular Make,Model or specific things to look for when choosing one
now i have that information.

Case Closed..................
 

davidbond21

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I will conduct my testing as Originally planned
with a Sillyscope, I have spoken to some
RF experts from several different companies
IE, Digital Sat as well as Broadband and
I have found the the type of scope needed.

And it CAN be done with a scope, as i knew
or why would i have asked.

I asked for help on what scope was needed
and no one could provide this information.

I was not looking for opinions.

I was looking for particular Make,Model or specific things to look for when choosing one
now i have that information.

Case Closed..................
Not that I'm an expert by any means, but it sounds like your "expert"(i.e. salesman) just made his commission for the day.

Also, if you don't want answers that you may not like, don't ask questions. A lot of folks on here may not be so called "experts" but are very knowledgeable about these matters and have many years of experience and technical know-how. Let us know how it works out.
 
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