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[Linrad] Re: WSE / Delta44 / Linad / MAP65 Windows local host setup

Hi Randy,

A brief follow-up to my message sent earlier today.  I 
downloaded your file 081026_2330.tf2 and used it to confirm
the two problems that I suggested you might have:

> 1. Your screen shot shows the signal level going into MAP65 
> is rather too high, +20 dB.  The main spectrum on the Linrad 
> screen also shows the noise baseline around +45 dB, higher 
> than desirable.  It seems that you should reduce the noise 
> level by about 20 dB.
> 2. Be sure to check the clocks on the computer running 
> Linrad+MAP65 and the computer on which you were sending a 
> test message into a dummy load.  The clocks should agree to 
> within a second or so.

I compiled a test version of MAP65 that divides the data 
samples in your *.tf2 file by 10, to bring the signal level 
into reasonable range.  It also chops off the first 3 
seconds of the file, thereby shifting the signal earlier by 
3 seconds.  The program then decodes your test signal 
correctly, as shown in the screen dump at

   http://physics.princeton.edu/pulsar/K1JT/WI7P.JPG .

The decoded message has DT = 2.3 s, so in your original file 
it would have been 5.3 s.  MAP65 searched over the range -2 
to +5 s.

So, it seems that you are very close to having everything 
working correctly!

	-- 73, Joe, K1JT

	-- 73, Joe, K1JT

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