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[aprssig] APRS Messenger now has APRS over PSK-63

Stephen H. Smith wa8lmf2 at aol.com
Mon Mar 1 09:32:25 UTC 2010


On 3/1/2010 12:29 AM, Frank or Barbara Rossi wrote:
> Was doing some testing with the new 1800Hz version with AGWPE free.
> Something is not calculated correct for APRS Messenger TX
>
> No matter what my radio dial must be tuned to 10.1515 LSB to RX the 
> AX25 at 2100Hz - 2300Hz
> That means I need the 2100Hz version running on 10.1515 LSB to put my 
> PSK63 APRS on top of the lower 2100Hz tone.
>
> Getting late and maybe not thinking straight.
> Chris, is the objective for the PSK63 signal to be on top of where the 
> lower AX25 tone is on LSB, or the upper tone on USB?


NOI!   NO!  NO!   The PSK carrier *SHOULD NOT* be on EITHER of the two 
tones of the "classic" FSK system.  You do not want to interfere with 
existing AX25 operations.

The whole intent is to have the PSK-mode activities on a *DIFFERENT* 
frequency from the classic FSK AX.25, so that both can proceed 
independently.

The objective is to have both modes audible in the receiver passband of 
a typical SSB receiver simultaneously (and pass through the same 
passband on transmit),  but far enough apart to not interfere with one 
another. You should hear them at different AUDIO frequencies that 
correspond to different RF frequencies.  The exact audio frequencies 
will depend on how you have tuned your SSB receiver (and what sideband 
you are using), but they SHOULD BE DIFFERENT.

To be specific, the single PSK frequency is 300 Hz ABOVE the higher FSK 
tone (if monitored on USB)  --OR-- 300 Hz BELOW the lower FSK tone (if 
monitored on LSB).   As mentioned in a couple of previous posts, the 
actual RF frequencies of the two FSK tones are 10.149.200 and 10.149.400 
.    The single PSK63 tone is half-way between the upper FSK frequency 
and the edge of the 30-meter band at 10.150.000;     i.e. at 10.149.700 .

This is far enough away to not interfere with classic FSK operations, 
but close enough to heard in the receiver at the same time.   This 
allows you to use two separate receiving systems (TNCs, computer 
programs, etc) simultaneously with a single receiver.  "Simultaneously" 
doesn't mean "alternately on the same frequency", but truly at the same 
time.

Note that if you want to use software receiving techniques for both 
modes, you will need TWO SOUND SYSTEMS on the computer -- one for each 
program. [Chris's original assumption was that you would use a hardware 
device like a KAM TNC on AX25, and the software/sound-card-based device 
only for PSK63.]




> If so you always need the frequency version of APRS Messenger that 
> matches the frequencies of your AX25 decoder ?

NO    But you do need the one appropriate for the tones you are using to 
receive AX25; i.e. 300 Hz away.

------------------------------------------------------------------------


Once again........ <note the operative word "alongside" -- NOT "On top of">

For operation alongside standard KAM Tones of 1600/1800 for AX25 FSK APRS:
      Use the 2100 Hz version of APRS Messenger
      and set radio to 10.147.600 MHz USB.

            -or-

      Use the 1300 Hz version of APRS Messenger
      and set radio to 10.151.000 LSB

[Paid-for AGWpe Pro version can also operate with these settings since 
it can be
configured for 1600/1800 standard "KAM" packet tones.]


For operation alongside freeware version of AGWpe on AX25 FSK APRS 
(audio tones are 2100/2300):
      Use the 1800 Hz version of APRS Messenger
      Set radio to 10.151.500 Mhz LSB.

[ Note that radio may need to be "hacked" to enable "general coverage 
transmit" since the dial indicates
that the suppressed-carrier frequency is "out of band" on 30 meters, 
even through the resulting RF
frequencies from these tones will be in-band.]

[The FREEWARE version of AGWpe only offfers the 2100/2300 tones.     The 
PAY-FOR AGWpe "Pro" version offers the choice of standard 1600/1800 KAM 
tones or the original 2100/2300 tones.]



------------------------------------------------------------------------

-- 

Stephen H. Smith    wa8lmf (at) aol.com
EchoLink Node:      WA8LMF  or 14400    [Think bottom of the 2M band]
Skype:        WA8LMF
Home Page: http://wa8lmf.net

NEW!    Universal HF/VHF/UHF Antenna Mounting System
http://wa8lmf.net/mobile/UniversalAntMountSystem.htm

"APRS 101"  Explanation of APRS Path Selection & Digipeating
http://wa8lmf.net/DigiPaths

Updated "Rev H" APRS http://wa8lmf.net/aprs
Symbols Set for UI-View,
UIpoint and APRSplus:



>>
>>
>> For operation alongside standard KAM Tones of 1600/1800 for AX25 FSK 
>> APRS:
>>      Use the 2100 Hz version of APRS Messenger
>>      and set radio to 10.147.600 MHz USB.
>>
>>            -or-
>>
>>      Use the 1300 Hz version of APRS Messenger
>>      and set radio to 10.151.000 LSB
>>
>> [Paid-for AGWpe Pro version can also operate with these settings 
>> since it can be
>> configured for 1600/1800 standard "KAM" packet tones.]
>>
>>
>> For operation alongside freeware version of AGWpe on AX25 FSK APRS 
>> (audio tones are 2100/2300):
>>      Use the 1800 Hz version of APRS Messenger
>>      Set radio to 10.151.500 Mhz LSB.
>>
>> [ Note that radio may need to be "hacked" to enable "general coverage 
>> transmit" since the dial indicates
>> that the suppressed-carrier frequency is "out of band" on 30 meters, 
>> even through the resulting RF
>> frequencies from these tones will be in-band.]
>>
>> The FREEWARE version of AGWpe only offfers the 2100/2300 tones.     
>> The PAY-FOR AGWpe "Pro" version offers the choice of standard 
>> 1600/1800 KAM tones or the original 2100/2300 tones.
>>
>>
>>
>> ------------------------------------------------------------------------
>>
>> -- 
>>
>> Stephen H. Smith    wa8lmf (at) aol.com
>> EchoLink Node:      WA8LMF  or 14400    [Think bottom of the 2M band]
>> Skype:        WA8LMF
>> Home Page: http://wa8lmf.net
>>
>> NEW!    Universal HF/VHF/UHF Antenna Mounting System
>> http://wa8lmf.net/mobile/UniversalAntMountSystem.htm
>>
>> "APRS 101"  Explanation of APRS Path Selection & Digipeating
>> http://wa8lmf.net/DigiPaths
>>
>> Updated "Rev H" APRS http://wa8lmf.net/aprs
>> Symbols Set for UI-View,
>> UIpoint and APRSplus:
>>

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