Pro-106 Air Band (Not full band)

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stlouisx50

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I was listening to the air band today (118 - 134) and heard a few towers tell piolits to switch frequencies to other control towers. I tried to program them in and the Pro-106 will not allow it. It will go to 124.366666 instead of the issued frequency 124.370 .

Is the Pro-106 not fully functional in this band? It would not surprise me, as it's not in other bands.
 

gewecke

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If this is the case, then simply create a list for conventional air frequencies and prog them into the list! :wink:

73,
n9zas
 

stlouisx50

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I can do that for sure, however it is not compatible with the TUNE function ither. I suppose the unit will have no luck searching for it in the search or air search function either :(



So many negatives and one positive.

I'd place this into the updates for PSR.
 

WA1ATA

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It will go to 124.366666 instead of the issued frequency 124.370 .
I'm pretty sure that the correct frequency is really 124.375MHz. Perhaps a more knowledgeable airband afficianado will correct me,but I think that current VHF airband spacing is 25kHz. Controllers will generally leave out the trailing "5" when giving the xx.x25 and xx.x75 frequencies. So when the controller says 124.37 he really means 124.375.
 

jfhtm350

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According to the specs in the manual, frequency coverage for that range is 108.000 - 136.9916 MHz in 8.33 kHz steps/AM.

If I press tune on my scanner and enter 108.0000 and then press up to go to the next frequency, it shows 108.008333. Now if I hold up on the button, I eventually get to 124.375000 (took a few minutes to get there) the exact frequency your looking for. So the Tune part of the scanner will get to that frequency in 8.333 kHz steps. So the aircraft search feature should do the same. As a matter of fact 124.366666 MHz is one step below 124.375000.

Have you updated your scanner from the radio shack website? If not then that could be where your problem is.
 

WA1ATA

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According to the specs in the manual, frequency coverage for that range is 108.000 - 136.9916 MHz in 8.33 kHz steps/AM.

I..... Now if I hold up on the button, I eventually get to 124.375000 (took a few minutes to get there) the exact frequency your looking for.
He wasn't trying to get that freq.

The problem is the original poster was trying to tune to 124.370, not the 124.375 that the controller actually means when he says "124.37".
 

hertzian

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This is one thing I don't like about the 106/PSR500 etc - the spacing while searching VHF airband is permanently set for 8.333 khz, but for most of us, 25 khz spacing is used. That makes searching take at least twice as long, and you can miss quick transmissions.

Try Airnav.com:
http://airnav.com/airports/

Enter your city, state and you can find plenty of airports, both international, and general aviation in your area, and get the freqs that way.
 

gewecke

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This is a old thread, but definately a good one.

For those of us who enjoy airband scanning, this is worth mentioning.
I never realized this shortcoming of the PRO series scanners. :roll:

73,
n9zas
 

kruser

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For those of us who enjoy airband scanning, this is worth mentioning.
I never realized this shortcoming of the PRO series scanners. :roll:

73,
n9zas
Do you really consider it a shortcoming?
If anything, it is making the scanner ready for when they make the switch to the new 8.333 kHz spacing which is coming soon to an air band near you. If the GRE only tuned in 25 kHz steps, you would not be able to monitor the new 8.333 spaced channels when they go live.
Most old scanners that have AM air band capability will not tune these new channels at all as they do not have the filters needed for proper channel seperation nor do they even know what 8.33 kHz spacing or steps are. The BC 780 XLT is one of the fine scanners that will no longer tune all the air band channels once 8.33 spacing is allowed. I'd imagine you can set it to a 5 kHz step size and it would still work but be off frequency slightly as it does not have very narrow filters so the new 8.33 channels will still be heard but may be off frequency by 3.33 kHz if using a step size of 5 kHz. I'd imagine that will be close enough if they even use the new narrow channels for voice comms. They may use them for digital modes only. It has been a long time since I read anything on the 8.33 spacing.

So I consider it a benefit myself and surely not a shortcoming.

I do wish they would have allowed the user to select 25 kHz steps though until the switch to 8.33 is made as it does add to the time needed to "search" through the entire air band. It in NO way affects the scanners ability to tune any of the air band channels directly that are in use today nor does it affect anything when you actually program your areas air band frequencies into a scanlist. Those will program and tune perfectly.
 
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airwolfbell222

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Maybe I can shed some light on this topic. I'm a certified helicopter and airplane instructor pilot.

The Pro-106 does have the correct steps set for the band.

In the US, we use 25 khz steps and in many other places in around the world they use 8.33 khz steps (especially europe)

If you take a calculator and divide 25 by 3, you'll come up with 8.33

As for frequencies read on the air that end in 25 khz steps, ie. 124.375, 135.525, etc...

Not all aircraft radios will display the entire 3 digits past the decimal, ie. (.375) so it's common for controllers and pilots alike to omit the last digit when issuing a frequency or reading back a frequency.

So most of the time you'll hear, CONTACT "********" CENTER ON 124.37 or CONTACT APPROACH ON 135.52

So if you're using the "direct tune" method, you'll have to remember to put in the "5"

In fact, a majority of pilots have know idea what "25khz steps" means or where in the radio spectrum they are transmitting, I teach my students a little more about radios than the average instructor just because I enjoy radios so much.
 

kruser

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Maybe I can shed some light on this topic. I'm a certified helicopter and airplane instructor pilot.

The Pro-106 does have the correct steps set for the band.

In the US, we use 25 khz steps and in many other places in around the world they use 8.33 khz steps (especially europe)

If you take a calculator and divide 25 by 3, you'll come up with 8.33
I pretty much understood all that but I think the issue is now that the 106 scanner is "searching" the in 8.33 steps.
Being as the US mostly uses 25 kHz steps, those that use the search feature with a GRE scanner must search in 8.33 kHz steps which doubles or triples the amount of time for the search to start over again from the beginning. Anotherwords, the 106 is searching two invalid frequencies for each valid frequnecy as it searches the entire band.

This seems to be the complaint now and I can agree as it does take some time to search across 25 or so MHz of spectrum in 8.33 kHz steps verse 25 kHz steps.

I myself knew about the fact that the controllers do not usually announce the entire frequency when they end with a 5 in the 3rd space past the decimal.
I did not realize that some radios do not even display that erd digt though so that does clear up the reasoning behind why the controllers do not announce the 3rd digit! I'm sure some pilot would become confused trying to figure out how to enter 124.375 on a radio that only shows 124.37!! Kinda kike when 911 became a reality, some would tell people to call nine-eleven instead of saying nine one one. I always read that bad things happened when panicked callers would try to find the "eleven" digit on the phones keypad!
So they pushed for advertisers and new stations to use the correct terminology of saying "nine one one" instead of "nine eleven" because too many people gave up when they could not find the "eleven" button on their phones.
I'm not sure if that was fully true and if anyone was harmed because they could not find the eleven button but I do remember news stations clarifying to call nine one one and any signs or advertisment that said to call nine eleven were pulled.
Kinda funny really how a simple thing like that can be mistaken so easily but I can definatly see it happening. And becauase of that, I could see a pilot become confused when he cannot figure out how to dial in the 5 digit in the 3rd place when his radio only has two digits after the decimal!

I'm surprised air did not go with channel numbers much like the railroads use instead of the actual frequency.

So with that said, I do agree that the GRE radios are not really using the correct step size when used here in the USA as we are still using the 25 kHz steps. Of course they will be fine if the USA does start using 8.33 kHz steps but as far as I know, that step size is not allowed in this country but I've heard more than once that it will be used at some time in the future here in the country.

You being a pilot, have you heard any recent talk of changing the step size in the USA to match the 8.33 kHz step size used in other countries?
Or is it still just talk or maybe the proposal has been shot down and a decision has been made to not change our step size. That is what I'd like to know is if there are any updates on using the 8.33 steps here. Or if the idea has been shot down and it has been decided to never use that step size here.
 

airwolfbell222

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You being a pilot, have you heard any recent talk of changing the step size in the USA to match the 8.33 kHz step size used in other countries?
Or is it still just talk or maybe the proposal has been shot down and a decision has been made to not change our step size. That is what I'd like to know is if there are any updates on using the 8.33 steps here. Or if the idea has been shot down and it has been decided to never use that step size here.
I have not heard anything on changing steps to 8.33 in the US, it's kind like when the government wanted to mandate all Emergency Locator Transmitters (ELT) be 406 mhz compliant. Alot of the aviation communities complained about this because of the cost involved.

I do think it's silly manufacturers are shipping radios in the US with 8.33 khz steps, even Uniden's new BC125AT searches in 8.33

It does take a heck of alot longer to search the 118-136 band.

I could only imagine that it would be a simple firmware update.

Maybe if enough of us complain to GRE and Uniden? Petition anyone?
 

kayi4cle

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Maybe if enough of us complain to GRE and Uniden? Petition anyone?
Well actually with Unidens you can set up a custom search (or 10 of them) of the air/milair bands (or any other frequencies) and select the 25 kHz step (which is among the dozen step-size choices). Nothing to complain about there! :lol:
 

kruser

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Well actually with Unidens you can set up a custom search (or 10 of them) of the air/milair bands (or any other frequencies) and select the 25 kHz step (which is among the dozen step-size choices). Nothing to complain about there! :lol:
Yep, one more reason I like Unidens over GRE's.

Really, I'd imagine GRE could fix this via firmware. Changing the step size for just the air band would be an easy one I think. I'd much rather them do like Uniden though and set default step sizes like is already done and then allow the user to alter the step size of ALL bands giving the user the choice to choose from all the step sizes available.
I'd also like to see both companies offer a fine tuning step size that is really small. Something like 100 Hz. Not sure that anyone would want to run a band search with that small of a step but it would be nice if you could do manual tunes in super small steps.
In the least though, they should allow the user to select custom step sizes for all bands and search ranges based on a list of all the default step sizes.
In todays age, fixed steps are stupid.
 

cherubim

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Yep, one more reason I like Unidens over GRE's.
I'd also like to see both companies offer a fine tuning step size that is really small. Something like 100 Hz. Not sure that anyone would want to run a band search with that small of a step but it would be nice if you could do manual tunes in super small steps.
In the least though, they should allow the user to select custom step sizes for all bands and search ranges based on a list of all the default step sizes.
In todays age, fixed steps are stupid.
100Hz (or even 50Hz) tuning would make sense for HF but not VHF/UHF.
 

kruser

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100Hz (or even 50Hz) tuning would make sense for HF but not VHF/UHF.
I admit that it is a pretty small step for the typical scanner.
My reasonig was based on something I found when using an Icom R2500 that also had the P25 digital card in it.
I found a few VHF single channel VHF users that the R2500 (or Uniden or GRE scanners) would not decode their P25 signals very well.
So I started playing with the R2500 one day as it has a super low tuning step like 1 hertz. I set the R2500 into P25 mode and tuned one of the stations that the 2500 and the scanner had a hard time with.
I set the tuning step as low as it would go but ended up back around 100Hz. I then started tuning off the channels center frequency and I'll be darned if the R2500 did not start decoding the P25 signal perfectly.
I think I found the sweet spot just under 1kHz from center frequency. I then tried that on another of the single channel P25 signals here and same thing, it started decoding the signals just fine. But I could not do this with any of the scanners because they do not allow such a fine tuning step.
I then setup a laptop attached to an Icom R7000 and an R9000 and used DSD from those radios. Sure enough, I had the same good results when I'd tune the R9000 off center frequency to match what I'd tried with the R2500.
I then tried the R7000 which has a 100 Hz step and it also allowed DSD to tune the P25 signals that the scanners will not.
So that was my reasoning for wanting a low tuning step like that as I'm failry certain a Uniden or GRE would also decode those same signals if I could offset them just under 1 kHz. A buddy at a communications shop used a service monitor on the signals that the scanner would not decode to see if the signals were off frequency but they were both dead on and both had perfect modulation.
One day I plan on moving the frequency of the PSR600 by the same amount and see if it will decode the signals. My guess is that it will.
I have the service manual for the radioshack version of the PSR600 and it is an easy to make adjustment but I've just not had the time to try it yet.
Right now, I can use my R2500 to decode the two stations I tested this on but I program the frequencies 800 Hz plus or minus the true center frequency and it decodes them both just fine. I forget and would need to fire up the R2500 to see if it was 800 higher or lower.
My point is that if you can clean up a P25 signal by using small steps off the true center frequency, I'd love to have this fine tune ability in a scanner.
I have not tested the theory on a multipath distortion problem site yet but I plan on also doing that as well. It sure works for single frequency P25 reception and it would be great if it worked on a trunked P25 site as well.
If it does, then darn right, I want a small tuning step so I can manually fine tune the systems that come in so badly now.
 

N1BHH

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When you hear an air traffic controller mention a frequency 124.37 he is using aircraft shorthand for 124.375. The third position beyond the decimal is rolled off, pilots will know this. Most avionics will automatically select the 5 when dialing in 124.37.
 
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