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- Subject: Archiving spectrum recordings (was: Morning TP Methodology?)
- From: Mark Connelly <markwa1ion@xxxxxxx>
- Date: Mon, 24 Sep 2018 04:43:10 +0000 (UTC)
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The 'spectrumarchive.org' site mentioned by Russ references the 1986 spectrum recording from Providence, RI that Craig Healy made via VCR. I dubbed this to a Perseus file several years ago.
Spectrum recording likely goes back to the early '60s (JFK era). Not long after that Gordon Nelson talked about a "Monday morning recorder" as a sort of joke in DX News but I'm fairly sure that his contracting work that included dealing with intelligence agencies clued him in to the existence of the real thing, most likely using professional-grade wide videotape similar to that in the TV broadcast industry. That would have predated Craig Healy's VCR set-up by a quarter century. Most likely converters with filters were used to move a chunk of spectrum into the ~3 MHz or so of spectrum that the tape system could record at decent dynamic range. Conceivably this conversion would be done in a way that even a slice of VHF spectrum used for aircraft communications could be moved into the recordable base band.
I believe that Thomas Witherspoon has in his possession a number of SDR files passed along by Dave Goren to whom I'd supplied a hard drive in 2014. Besides the 1986 and 1991 "VCR DX" files, a good number of 21st century DXpedition recordings were included. Pick the right file and you could relive the programming of long-gone blasters such as 1314 Norway.
The hard drive also included a library of aircheck audio files, many from the '60s / '70s heydays of Top 40 radio with an emphasis on the Boston and NYC markets.
It would be good if the site at least put up a directory of its file holdings in both the RF and audio domains, if not going all the way to allow downloads. The hard drive I contributed is likely just a drop in the bucket of their total holdings.
Mark Connelly, WA1IONSouth Yarmouth, MA
<<
In the discussion of history or recordings, some of you might want to check
out this site:Â spectrumarchive.org. For SW, there's shortwavearchive.org.
Both of these are run by Thomas Witherspoon in NC, who gave a most
interesting presentation last March at the annual SWL Winterfest. He might
be interested in some recordings. I had promised him some from my old
Northern NJ audio recordings but haven't been able to make the time to
cherry pick those and send them on.
Russ Edmunds
WB2BJH
Blue Bell, PA
Grid FN20id
>>
Mark Connelly, WA1IONÂ
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