Hi All,
Sorry, I just discovered that my attachment size limit is only 3.8 MB.
That should still be enough for 7 minutes at 8 kHz, 8 bits.
73,
Stewart
----- Original Message -----
From: "Stewart Nelson" <[email protected]>
To: <[email protected]>
Sent: Tuesday, May 01, 2001 12:12 PM
Subject: Re: LF: Wolf Tests
Hi Mike, Jim, and all,
I would like to get copies of your recordings, when you failed to copy Larry,
so I can try to improve WOLF's QRM rejection and tracking. Recordings from
others are also welcome. Please include your estimates of sample rate, center
frequency, and original RF Tx frequency.
Seven minutes, at the time you feel decoding should have been most likely,
should be plenty. Five minutes is probably adequate.
My mail server will only accept attachments of up to about 7 MB. If you
have problems with upload speed, you might want to send less than that.
To reduce file size, if the original recording is 16-bit, convert to
8-bit. In Cool Edit, use Edit->Convert Sample Type. That won't add
significant noise, provided that frequent signal peaks are -6 dB or
higher. If necessary (for file size), convert the sample rate to
8000 Hz in the same operation. If the original level is low, try
Transform->Amplitude->Normalize first. Normalize to about 80%.
ZIPping the resulting 8-bit file should make it a little smaller.
Of course, if you have a server to which you can upload the file, do
so and just send me the URL. Don't bother with any file conversions
if upload speed and server space are not problems. I'll let you know
as soon as I fetch the data, so you can delete it and reclaim the space.
73,
Stewart KK7KA
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