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

Mike Miller mike.kc9doa at sbcglobal.net
Sat Nov 4 23:42:11 UTC 2006


I burned another cd from the same file and that one works. The 
first must have been a  bad disk or burn.

> 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:
> > 
> > 
> > 
> > 
> > _______________________________________________
> > aprssig mailing list
> > aprssig at lists.tapr.org
> > https://lists.tapr.org/cgi-bin/mailman/listinfo/aprssig
> 
> 
> 
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