30 To 50 MHz, How Many Channels?

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haleve

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I'm experimenting with a 1000 channel scanner to program the entire VHF low band allocation to scan for local, skip, tropo ducting, whatever, I've checked various spectrum allocation charts & cant quite come up with a recently confirmed step plan like 10 kHz, 20 kHz, 25 kHz or 5 kHz, can anybody tell me what the actual frequency steps are & the actual total amount of allocated channels? Best I can come up with is 20 kHz steps totaling 980 channels, am I on target or no cigar?
 

Voyager

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I'm experimenting with a 1000 channel scanner to program the entire VHF low band allocation to scan for local, skip, tropo ducting, whatever, I've checked various spectrum allocation charts & cant quite come up with a recently confirmed step plan like 10 kHz, 20 kHz, 25 kHz or 5 kHz, can anybody tell me what the actual frequency steps are & the actual total amount of allocated channels? Best I can come up with is 20 kHz steps totaling 980 channels, am I on target or no cigar?

Close, but there are about 1286 frequencies. The Federal bands often use 10 kHz steps. The Land Mobile segments are 20 kHz steps.
 

haleve

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VHF Low Band Monitoring

Thanks Idlemonitor & Voyager for your quick & informative suggestions, to start with I think I'll get my feet wet by searching in 5 MHz ranges as suggested, I noticed on kkn50's logs that military ops appears to be utilizing 25 khz spacing while everybody else is using 20 khz spacing, is that an accurate presumption? Also I saw in another thread that kkn50 uses a horizontal dipole, would that be a logical preference for DX'ing since I believe long distance skip & tropo ducting skywaves sometimes change polarity instead of a vertical dipole that's generally used for dedicated local communications?

BTW: I've tried VHF low band DX'ing before with no luck but realized I didn't give this aspect of the hobby not nearly enough time & residential restrictions in New York & Central Florida hampered my ability to utilize even the most basic equipment for marginal success at best, right now I just received residential permission to install a 10' mast mounted vertical homebrewed dipole cut to 40 MHz on my terrace using RG-8X, again, thanks for your time, patience & assistance.
 

IdleMonitor

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Thanks Idlemonitor & Voyager for your quick & informative suggestions, to start with I think I'll get my feet wet by searching in 5 MHz ranges as suggested, I noticed on kkn50's logs that military ops appears to be utilizing 25 khz spacing while everybody else is using 20 khz spacing, is that an accurate presumption? Also I saw in another thread that kkn50 uses a horizontal dipole, would that be a logical preference for DX'ing since I believe long distance skip & tropo ducting skywaves sometimes change polarity instead of a vertical dipole that's generally used for dedicated local communications?

BTW: I've tried VHF low band DX'ing before with no luck but realized I didn't give this aspect of the hobby not nearly enough time & residential restrictions in New York & Central Florida hampered my ability to utilize even the most basic equipment for marginal success at best, right now I just received residential permission to install a 10' mast mounted vertical homebrewed dipole cut to 40 MHz on my terrace using RG-8X, again, thanks for your time, patience & assistance.
Get yourself a small discone scanner antenna and you'll do just fine with it.

And again, maximize your searching when searching in your 5mhz ranges set your bandwidth to 5khz. Most of the things you had mentioned are all divisible by 5 anyways so you're not gonna miss anything. If anything you may find more.
 

BushDoctor

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Thanks Idlemonitor & Voyager for your quick & informative suggestions, to start with I think I'll get my feet wet by searching in 5 MHz ranges as suggested, I noticed on kkn50's logs that military ops appears to be utilizing 25 khz spacing while everybody else is using 20 khz spacing, is that an accurate presumption? Also I saw in another thread that kkn50 uses a horizontal dipole, would that be a logical preference for DX'ing since I believe long distance skip & tropo ducting skywaves sometimes change polarity instead of a vertical dipole that's generally used for dedicated local communications?

BTW: I've tried VHF low band DX'ing before with no luck but realized I didn't give this aspect of the hobby not nearly enough time & residential restrictions in New York & Central Florida hampered my ability to utilize even the most basic equipment for marginal success at best, right now I just received residential permission to install a 10' mast mounted vertical homebrewed dipole cut to 40 MHz on my terrace using RG-8X, again, thanks for your time, patience & assistance.

Today i heard fort worth tx to virginia a distance of 1400 miles on 29.66 on both my desktop as well as my pro 96 rubber duckie. my desktop consists of a a quad configuration 300 inches total length (4 sides) fed half way up one side works great on an outside facing wall the top is at ceiling level the bottom is half way between the lower window sill and the floor facing south/west held in position with wood dowels rubber banded to the curtain rods at the top and the bottom with dowels secured to the inside of the window frame pointing down with round eyelets screwed into all 4 wood dowels top and bottom for the wire to make its 45 degree turns works great for low band and skip i have a switch in the bottom for some other then low bands in the right side corner just down from the feed (32inches or so) sometimes the switch open makes stations come in better on other bands and a 6 inch whip in the top of the radio works fine for 460 even with the quad hooked up
 

nd5y

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In the US the 30-50 MHz band is broken up into federal and non-federal subbands.
Federal users (non-military and not using SINCGAR radios) are on odd 20 kHz steps in the federal subbands.
Non-federal users are on even 20 kHz steps in the non-federal subbands.
Military users with frequency agile radios are normally on 25 kHz steps and often in the non-federal subbands.

Some of the later model Uniden scanners can search the entire band in 5 kHz steps about 3 times faster than they would be able to scan all of the individually programmed channels.
 

haleve

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30 to 50 MHz Low Band

The reason why I wanted to physically program every low band frequency into my scanner was in case I wanted to sit on a particular channel of interest without having to reprogam the search limits again, after reading some of you guys very informative & helpful replies I've noticed that the BCD996XT is able to scan 25,000 channels & that's much more then I'll ever need but does anybody know if this scanner is sensitive & selective enough with acceptable dynamic range on low band? I found a great low band vertical dipole DIY antenna project on 6 Meter Repeater Antenna 1/2 Wave Coaxial Vertical Antenna Design that should work for me.
 

mm

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If you use 20 KHz channels then you will miss some stations who are operating in between the 20 KHz spaced channels so I would go for 10 or 5 KHz channel steps.

I frequently hear South American stations on frequencies such as 29.790 and 33.61 MHz for example.

If you used 20 KHz spacings starting at 29.700MHz for example you would have missed any stations in between 29.78 and 29.80 MHz.
 

nd5y

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The reason why I wanted to physically program every low band frequency into my scanner was in case I wanted to sit on a particular channel of interest without having to reprogam the search limits again,

I don't know what you are using but as far as I know every scanner made recently allows you to hold on a frequency in search mode or manually enter one to sit on without reprogramming anything.
 

Voyager

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I have definitely heard Military users on non-25 kHz steps, and 10 kHz off other channels. But, maybe they changed.
 

haleve

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30-50 MHz Channel Spacing?

If you use 20 KHz channels then you will miss some stations who are operating in between the 20 KHz spaced channels so I would go for 10 or 5 KHz channel steps.

I frequently hear South American stations on frequencies such as 29.790 and 33.61 MHz for example.

If you used 20 KHz spacings starting at 29.700MHz for example you would have missed any stations in between 29.78 and 29.80 MHz.

Thanks mm, well at least I now know I can receive low band frequencies because my BCT8 was receiving CB skip a few weeks back which is close enough to low band & that was with a RS center loaded telescoping whip on my desk 15' from a south facing window 5 stories up in Broward County in the afternoon, so my best bet is to program all the frequencies in 5 kHz steps to guarantee receiving any & everything? Are there any software programs that would allow me to download them into a BCD996XT from my PC or do I have to program them in by hand? I heard that trying to program even one frequency into these new dynamic memory scanners is a beast, thanks again for your input.
 

haleve

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30-50 MHz Band

I don't know what you are using but as far as I know every scanner made recently allows you to hold on a frequency in search mode or manually enter one to sit on without reprogramming anything.


Initially I was searching with a vintage UBC9000XLT but every time I tried to select up an individual frequency to monitor from search mode, the search feature would turn itself off & I'd have to enter the frequency in a separate bank then reprogram the search parameters on bank A, I initially thought that maybe due to it's vintage the 9000 may have become deaf on low band or that it had bad caps but I hooked up a long wire to it & programmed WWV on 25 MHz & selected up AM mode & it received just fine, so much for that, I'll probably add a discriminator tap this weekend & set it aside to experiment with either ATCS or AIS since it only scans 500 analog channels, not much use for anything else to be frank.
 

kkn50

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I'm using a Uniden BCD996XT dedicated to low band and programmed as:

- Every frequency from 30 to 60 MHz in 25 KHz steps with a CTCSS of 151.4 (for 150.0) for military

- All US FCC allocated frequencies between 29.7 and 50.0 MHz

- 29.70-30.55, 32.00-32.99, 34.00-34.99, 36.00--36.99, 38.00-38.99, 40.00-41.99, 46.60-46.99, 49.61-49.99 in 10 KHz steps

- Various foreign frequencies that I have found while searching

I don't know how many channels that is but the scanner is not full.

Scanner runs 24/7 with Butel software and saves each transmission as a separate file whose name is the frequency and time.

Works well for me.
 

haleve

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NICE!!!!!!

I'm using a Uniden BCD996XT dedicated to low band and programmed as:

- Every frequency from 30 to 60 MHz in 25 KHz steps with a CTCSS of 151.4 (for 150.0) for military

- All US FCC allocated frequencies between 29.7 and 50.0 MHz

- 29.70-30.55, 32.00-32.99, 34.00-34.99, 36.00--36.99, 38.00-38.99, 40.00-41.99, 46.60-46.99, 49.61-49.99 in 10 KHz steps

- Various foreign frequencies that I have found while searching

I don't know how many channels that is but the scanner is not full.

Scanner runs 24/7 with Butel software and saves each transmission as a separate file whose name is the frequency and time.

Works well for me.

Now that's what I call "X-TREME LOW BAND SCANNING".

It looks as if I'm also going to get the BCD996XT too since I am looking to scan every programmed frequency from WWV 25.MHz as a beacon frequency to 54 MHz in 5 kHz steps since I was told in another thread that scanning with 25 kHz, 20 kHz or even 10 kHz I would miss some frequencies & 5 kHz steps would guarantee hearing everything, if that's innacurate, by all means please let me know, how would I go about programming it? I hear the new Unidens are a monster to program from the front panel, do I have to make up some kind of spreadsheet by hand or is there a program that I can use? I didn't even know programs existed whereby you could store active frequencies much less identify them, does it have the ability to record audio too or am I asking to much? I have a bunch more questions but everything in time, Thanks in advance for your time.

BTW: I appreciate your logs, it's a dedication rarely seen in many forums nowadays, thanks for that also.
 
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mancow

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I'm using a Uniden BCD996XT dedicated to low band and programmed as:

- Every frequency from 30 to 60 MHz in 25 KHz steps with a CTCSS of 151.4 (for 150.0) for military

- All US FCC allocated frequencies between 29.7 and 50.0 MHz

- 29.70-30.55, 32.00-32.99, 34.00-34.99, 36.00--36.99, 38.00-38.99, 40.00-41.99, 46.60-46.99, 49.61-49.99 in 10 KHz steps

- Various foreign frequencies that I have found while searching

I don't know how many channels that is but the scanner is not full.

Scanner runs 24/7 with Butel software and saves each transmission as a separate file whose name is the frequency and time.

Works well for me.

How long does it take to make a complete pass? I switched to the 796 because it's so much faster. I might load up the BCT15 using your method and give that a go though.
 
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