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[linrad] Linrad experience today

Hello, all!

I was able to get some time to play with Linrad on EME today, using
Leif's new RX2500.  I just used a TUF-1H mixer with LO at 141.548 as
downverter to the RX2500.

I easily heard DL1EJA and I2FAK on CW EME (not working each other).

The noise level was very high here today.  Linrad did a good job of
getting rid of the noise.  It made JT44 signals that I otherwise
couldn't hear Q5 audio copy.

I used Linrad as my receiver and fed the output of Linrad into JT44 and
copied G4FDX and S52LM working via JT44 EME, and then G4FDX calling CQ
with Linrad.

Finally, K9MRI and AL7EB were trying to work each other on CW.  They
could not copy each other, but I was able to pull out complete calls
with Linrad and COH2 mode.

I recorded all of this stuff as "S" files (I made 10 of them in all),
but Linrad is telling me "Can not open file Eme1 eme1par" so I cannot
play them back to experiment or to make wave files to put on the  web,
etc.  I know enough to have set the permissions on the files so that I
can 'execute' them; still no dice.

The main 'find' is that I was able to make the Linrad delay short enough
that JT44 worked with no problem!  I didn't even need to reset the
computer clock or use the 'sec dec' function in JT44.  I didn't do the
experiment of seeing if JT44 'would have' copied G4FDZ/S52LM without
Linrad.  But it did fine with Linrad, which is new information.

I am pleased that the RX2500 is performing very well, even though I
don't have the front end I am using to mix down from 144 MHZ to 2.5 MHz
to feed it anywhere NEAR optimized yet.

I will email Leif to see if there is anything I can do to resurrect the
'S' files that don't want to be read...


Roger Rehr
W3SZ   FN20ah
2 Merrymount Road
Reading, PA  19609-1718