8.33 spacing
- Thread starter bearcatrp
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nd5y
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What YouTube moron did you learn that from?
See Section 5.2 Communication Procedures on page 30 of
The introduction of 8.33 kHz channel spacing has resulted in a 6-digit channel
numbering scheme, where the 8.33 kHz channel designators differ from the actual
frequency; e.g. 8.33 kHz channel 132.035 tunes the frequency 132.0333 MHz.
prcguy
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Its the way some transceivers are programmed. T`hey don't take in the specific 8.33KHz frequency but instead are programmed up to about the 5KHz point and the radio automatically knows you want an 8.33KHz channel and it gets programmed correctly.
ATC could even say Channel 79 (or whatever they want to call it) and the TRX would operate on 118.0083. But they decided to name this Channel 118.01.
I just speak for Europe: here we use channels since 8.33KHz-Steps were established but I‘m pretty sure it’s the same in the US.
I just speak for Europe: here we use channels since 8.33KHz-Steps were established but I‘m pretty sure it’s the same in the US.
Ubbe
Member
I still haven't heard any transmissions using 8.33 raster or any modulation being reduced with less treble in its audio to fit within a 8.33 channel. They have changed the name of the channels and the local airports tower frequency of 118.100 are called 118.105 but are still on the exact 118.100 frequency and with the same modulation level and frequency range as always. And that goes for all frequencies I can hear for ATC.
But then all transmissions seems to always have been around a 9KHz bandwidth so not that far from 8.33KHz so probably no modulation changes where necessary, if using guard channels.
/Ubbe
But then all transmissions seems to always have been around a 9KHz bandwidth so not that far from 8.33KHz so probably no modulation changes where necessary, if using guard channels.
/Ubbe
Testing out my new R15 on airband. Doing the same thing as my 160DN was doing. Switched it over to 8.33. Most static crap went away. Am picking up aircraft not on the 25khz frequencies.
prcguy
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If the frequency displayed is a 25KHz channel like 127.300, 122.850, etc, then the radio may be going narrow band and that is reducing demodulated high frequency audio and cleaning things up.
Some of the frequencies are in the 25KHz channel but others are showing 8.33 KHz channel. Thanks prcguy.
Doing it now. Finding out the R15 is listening to a conversation while the 160DN locks on the frequency but no voice. Thats disappointing for the 160. This is on 25KHz spacing frequency. Still getting more hits on the 8.33 spacing.
But are the hits on frequencies only in the 25 kHz band plan? You are not seeing hits on frequencies in the splits are you?
Am getting hits on splits more than on 25khz spacing.
According to others, the “new” 8.33 kHz split frequencies are not yet used in the United States other than for some testing purposes. I’ll let someone else confirm that statement.
Have read those posts stating that. Think I’ll use my R30 to replace the 160 on the 25Mhz spacing as it’s allot more sensitive.
I have a 160 and it works just fine on the aircraft band. Also have a R30 and they both seem about the same reception wise.
I also did a search using 8.33 spacing and got zero hits. I'm in a heavily populated area with lots of aircraft traffic.
One caveat is I do get intermod on the 160 that I don't get on any other radio, Uniden or otherwise.
My R15 was locked on a frequency listening to a long conversation while my 160 scanned right past it without locking on. Also, had my R15 scanning on 25 Mhz spacing and was getting close by frequency interfering. Am receiving hits on both 8.33 and 25 Mhz spacing. Are those foreign planes coming into MSP international supposed to be switching to 25 Mhz frequencies?
Yes; any aircraft using VHF ATC in the USA should be using the 25KHz spaced freqs.
