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

Christopher T. Day CTDay at LBL.Gov
Sat Nov 4 10:12:52 CST 2006


Have you tried the following:

1) Open up Windows Media Player.
2) Start to rip the files from the test CD.
3) Abort the rip.
4) Go back to the play list.

This seems to get Media Player to recognize the audio tracks and can now
play them. [As to why this works, I have no idea.]

	Chris - AE6VK

-----Original Message-----
From: Mike Miller [mailto:mike.kc9doa at sbcglobal.net] 
Sent: Friday, November 03, 2006 10:24 PM
To: Stephen H. Smith; TAPR APRS Mailing List
Subject: Re: [aprssig] *** APRS TNC Test CD Now Available ***

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, 

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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