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[aprssig] *** APRS TNC Test CD Now Available ***

Mike Miller mike.kc9doa at sbcglobal.net
Sat Nov 4 06:23:43 UTC 2006


I just tried burning the Nero version of the test CD. I unzipped 
the file and double clicked the .nrg file and Nero burned the 
CD. Windows explorer can't see the data files and it crashes 
Windows CD player. I tried playing it in a DVD player that plays 
audio CDs and it reports no supported files found. Nero disc 
info shows track 1 as a data track and the rest as audio tracks.
The CD is not compatible with anything I have. Nero 6.3.1.1, 
Win2Ksp4.

Mike kc9doa

Has this been resolved?

> ***   APRS TNC Test CD Now Available   ***
> 
> 
> I have produced a CD containing signals for testing and comparing
> the performance of different packet TNCs, and radios that might
> be used with these TNCs.  The recordings of live off-the-air APRS
> activity are also useful for demonstrations in locations where
> live signals aren't available, such as a basement conference
> room.
> 
> This disk is a "CD-Plus" combination disk that contains CD-ROM
> data files viewable on a computer, and standard CD audio files
> playable on any normal home or car audio CD player, boombox or
> DiskMan.
> 
> The audio files could also be played on an old CD-ROM drive
> standalone, without a computer, by connecting the TNC under test
> to the drive's front panel earphone jack, or to the 4-pin analog
> audio jack on the drive's rear panel. (A CD-ROM drive normally
> doesn't need computer support to play audio CDs. A drive with a
> front panel volume control and track-select button is preferred.)
> 
> Playing back standard CD audio rather than CD-ROM .wav or .aiff
> audio data files avoids the timing errors and incorrect playback
> sample rates that often accompany low-cost software-based  PC
> sound systems (i.e. motherboard AC97-based systems).
> 
> Details on the disk, links for downloading the 530MB image file
> for creating this CD, and a link for purchasing a ready-made CD,
> are located on my website at:
> 
>       http://wa8lmf.net/TNCtest
> 
> Scott, N1VG, of OpenTrac fame ( http://opentrac.org ) is handling
> the sale of recorded disks on his Argentdata e-commerce site, and
> has also graciously volunteered to host the large downloadable CD
> image files on his server.  
> 
> 
> 
> 
> 
> About The Tracks
> 
> 
> ---- Track 1 is an off-the-air recording of 40 minutes of
> activity on 144.39 MHz in Los Angeles, California, during the
> afternoon rush hour at about 5:00 PM when the channel is totally
> saturated to several hundred percent of the Aloha threshold. It
> contains a variety of over- and under- deviated signals, packet
> collisions, rapid-fire packets with practically no pause between
> them, raw NMEA string trackers, TinyTraks, clueless idiots using
> CW ID on packet, etc. All periods of dead air over about 1 second
> have been edited out so that 40 minutes of real-life activity
> have been compressed to 25 minutes on the CD.
> 
> This track is intended to be played back directly into TNCs to
> compare the performance of various TNCs "under fire" in the real
> world . The rapid pace of the packets should be a good test of
> the ability of buffers in TNCs and associated applications to
> hand a rapid flow of data without overrunning.
> 
> 
> 
> ---- Track 2 is identical to Track 3 except that a precise 
> 6db-per-octave/20db-per-decade de-emphasis between 300 and 3000
> Hz has been applied to simulate the typical de-emphasis found at
> the volume control or speaker output of the typical land-mobile
> receiver. This can used to evaluate the relative performance of
> TNCs in handling raw non-deemphasized discriminator audio vs
> de-emphasized speaker audio. The effectiveness of jumper-selected
> equalization networks available inside some TNCs can also be
> tested. This track was created by applying the graphic equalizer
> filter in Adobe Audition set to simulate the standard EIA
> land-mobile radio de-emphasis curve.
> 
> 
> 
> ---- Track 3 is a recording of a Kenwood D700 transceiver sending
> a Mic-E position report, taken from the wideband low-distortion
> discriminator output of an IFR1500 service monitor.  This
> recording of a single packet was then copied and pasted
> repeatedly in the Adobe Audition audio editor. The result is 20
> bursts each minute, for 5 minutes, for a total of 100 absolutely
> identical packets.
> 
> This track is intended to modulate an RF signal generator.
> Connect the CD player to the external modulation input of a
> generator, and set the playback level so that the data bursts
> deviate the generator about 3.5 KHz. Connect a radio's receive
> audio output to the TNC under test. Connect the RF generator to
> the radio's antenna input. While the recording is playing,
> gradually decrease the generator RF output level until the TNC
> starts failing to decode. Since the recording contains exactly
> 100 bursts, counting the number of successful decodes can
> directly indicate the percent success rate at various RF carrier
> levels.
> 
> Possible uses of this track:
> 1)     Compare different TNCs connected to the same radio.
> 
> 2)     Connect the same TNC to different radios to compare the
> weak-signal data performance of various receivers.
> 
> 3)     Evaluate the relative receive performance of audio taken
> from the radio's speaker versus audio taken from dedicated "data"
> or "packet" jacks or outputs. (De-emphasis and audio bandwidth
> may be different at these two sources.)
> 
> 
> 
> --- Track 4 is an off-air recording of 25 minutes of a single
> mobile D700 beaconing every 12 seconds (maximum beacon rate) on a
> quiet channel (no other stations) while driving around the San
> Gabriel Valley area of Los Angeles. The signals were monitored in
> Pasadena, California. Most of the drive test course was 8-10
> miles from the fixed station, far enough away from the monitoring
> fixed station to create some mobile flutter, multipath and loss
> of quieting. In several stretches, several successive packets are
> audible on the recording but failed to decode with the AGW packet
> engine.
> 
> Again, this recording was taken from the non-de-emphasized direct
> discriminator output of a Yaesu FT-1500b via the 6-pin mini-din
> data connector.
> 
> This track is intended to be played back directly into TNCs under
> test. An APRS application running on a computer attached to the
> TNC should create a realistic moving object.
> 
> 
> 
> 
> The three following tracks are for TNC alignment rather than
> testing. They are intended to evaluate TNC demodulator tolerance
> to tone "skew" (unequal levels of the 1200 and 2200 Hz tones).
> 
> 
> ---- Track 5 is a direct recording of one minute of a KPC3+ TNC
> in the CAL mode sending the alternating 1/0 test pattern (i.e.
> alternating between 1200 and 2200 Hz tones) with both tones at
> the same amplitude.
> 
> ---- Track 6 is the same recording with a precise 6 dB/octave 20
> dB/decade DE-emphasis applied as in Track 3 above.
> 
> ---- Track 7 is the same recording with a mirror-image precise 6
> dB/octave 20 dB/decade PRE-emphasis applied.
> 
> 
> 
> 
> 
> 
> --
> 
> Stephen H. Smith    wa8lmf (at) aol.com
> EchoLink Node:      14400    [Think bottom of the 2M band]
> Home Page:          http://wa8lmf.com  --OR--   http://wa8lmf.net
> 
> 
> NEW!  TNC Test CD
>   http://wa8lmf.net/TNCtest
> 
> JavAPRS Filter Port 14580 Guide
>   http://wa8lmf.net/aprs/JAVaprsFilters.htm
> 
> UI-View Misc Notes and FAQ
>   http://wa8lmf.net/aprs/UIview_Notes.htm
> 
> "APRS 101"  Explanation of APRS Path Selection & Digipeating
>   http://wa8lmf.net/DigiPaths
> 
> Updated "Rev G" APRS            http://wa8lmf.net/aprs
> Symbols Set for UI-View,
> UIpoint and APRSplus:
> 
> 
> 
> 
> _______________________________________________
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