22039Re: [perseus_SDR] 1986 and 1991 Perseus files
- Mar 2, 2014I have copy/pasted the links one at a time, since they are not hyperlinks, into a browser window. The site does not show up nor is there a way to download the files. Perhaps some once can provide a method to download the the files.
From: "MarkWA1ION@..." <MarkWA1ION@...>
Sent: Saturday, March 1, 2014 10:54 PM
Subject: [perseus_SDR] 1986 and 1991 Perseus files
The following Perseus format files dubbed from videotape RF captures are now available:1 MAY 1986, 0759-0801 UTC, 410-2010 kHz (Craig Healy - metro-Providence, RI, USA)http://chowdanet.com/markc/rf/19860501_0759-0801z_410-2010.wav2 APR 1991, 0759-0801 UTC, 810-1610 kHz (Mark Connelly - metro-Boston, MA, USA)http://chowdanet.com/markc/rf/19910402_0759-0801z_810-1610.wavThese were reduced to 2 minutes each from longer files by use of the Chuck Hutton 'WavChopper' program.Earlier information on the topic appears below.Mark Connelly, WA1IONSouth Yarmouth, MA, USA<<I am fascinated by the conversion of a broadband vhs tape recording to aPerseus file. Well done......So aligned freq for both, set PC date back, and played into perseusaerial socket and press record?? Is that how it was done???And it worked????Any chance of posting a 5m or so toth Perseus file somewhere???For 1986 and 1991....??? Night time files would be of interest as well...Ken, Scotland>><<I have converted the two best spectrum capture videotapes (1986, 1991)to Perseus files and then dubbed off a few ID's with Total Recorder.This is what I have so far:http://chowdanet.com/markc/dx_audio/id1_19860501_0500e.mp3ID's 5 a.m. EDT / 0900 UTC, 1 MAY 1986 from metro-Providence, RI (CraigHealy VCR DX spectrum capture tape): WWKB-1520 NY, WTOP-1500 DC,WPTR-1540 NY, WQXR-1560 NY, WCAU-1210 PA, WRCP-1290 RI, WHIM-1110 RI,WHJJ-920 RI, WHN-1050 NY, WINS-1010 NY.===http://chowdanet.com/markc/dx_audio/id1_19910402_0500e.mp3ID's 5 a.m. EST / 1000 UTC, 2 APR 1991 from Billerica, MA (MarkConnelly VCR DX spectrum capture tape): WHDH-850 MA, WCAP-980 MA,WBZ-1030 MA, WADN-1120 MA, WNEW-1130 NY, WMJX-1150 MA (ID for FM),WKOX-1200 MA, WEZE-1260 MA, WJDA-1300 MA, WRCA-1330 MA, WFEA-1370 NH,WLLH-1400 MA, WXKS-1430 MA, WTOP-1500 DC, WSSH-1510 MA, WQXR-1560 NY.===Mark Connelly, WA1IONSouth Yarmouth, MA>><<That's basically it Bill, though I think that 2 MHz would be about thetop of the baseband range. Storing higher frequency blocks wouldrequire a downconverter stage. That, as far as I know, was theintelligence agencies' method employed at places like Menwith Hill (UK),Resolute Bay (Canada), Thule (Greenland), Incirlik (Turkey), theAleutian Islands, and numerous other monitoring outposts in the '60sto snoop on the Russian bear (and probably the ChiCom's too).Regarding Craig's comment, I have identified that his recording startsat 0859 UTC on 1 MAY 1986. Lots of news about the Chernobyl nuclearreactor accident a few days earlier. Fun to hear 1560 WQXR doingclassical, as well as hearing contemporary hit music and oldies onnumerous other stations that are now boring talk ... aah the good olddays! No TA's or Latin Americans, but what do you want with only about40 dB of dynamic range?So, besides my 1991 stuff, now we have Perseus files from 1986!Mark Connelly, WA1IONSouth Yarmouth, MA-----Original Message-----From: Bill Nollman <billct97@...>To: CapeDX <CapeDX@yahoogroups.com>; badx <email@example.com>; am<am@...>; irca <irca@...>Sent: Fri, Feb 21, 2014 8:32 pmSubject: RE: [CapeDX] Perseus captures from 1991OK, let me understand this… the idea was to take 0-150MHz add a 60Hzsync signal to keep the VCR happy, store it to tape through the VideoIN jack then on output simply remove the 60Hz and you basically havecoming out what you put in? So simple its silly! I once used a Hi-FiVCR to capture 8 hours of FM DX audio. Hardly genius.From: CapeDX@yahoogroups.com [mailto:CapeDX@yahoogroups.com] On BehalfOf Mark ConnellySent: Friday, February 21, 2014 4:56 PMTo: firstname.lastname@example.org; am@...; CapeDX@yahoogroups.com;irca@...Subject: [CapeDX] Perseus captures from 1991I finally got around to going through a box of VHS videotapes from thelate '80s / early '90s spectrum capture experiments, as originallydeveloped by Craig Healy (NG1U), and mentioned in this article:http://chowdanet.com/markc/webpage/WA1ION/vcrdx.pdfThere were about 6 tapes in the box. Two of these, when played into areceiver, had reasonable performance.One of these was the tape Craig had originally supplied me. This wasmade at his QTH near Providence, RI. The whole AM band is captured.Sensitivity on the lower half was quite low so it's primarily the localstations such as 630, 790, and 920. Some skip signals can be heard onthe upper half of the dial. I still have to review the tape todetermine the exact date and times of recording. Items on a news /sports station, possibly with some Google follow-up, will nail down thedate. At some point in the recording there should be a time check onone station or another. I looked into the lower shortwave spectrum butnoted little in the way of "real" (non-birdie) signals, so no CHU orWWV assistance on the time.The second tape was one I made at Billerica, MA in April 1991 duringthe "wee hours" of the morning: 0643-1043 UTC. Because 50 kW WRKO on680 is only 2.8 miles / 4.5 km from the receiving site, a notch filterfor 680 was inserted ahead of the VCR input. Usable sensitivity forthe capture came in starting around 800 kHz and up.One thing that must be kept in mind is that this primitive version ofspectrum capture had a rather small dynamic range: only about 30 to 40dB from a hashy noise floor up to the level of a strong local on theverge of causing distortion and spurs. The tapes, obviously, are notgoing to produce much in the way of weaker signal DX.Before the tapes have a chance to deteriorate, I'm porting at leastsome of the contents over to Perseus files. This also gives a readymethod for sharing the experiment results with others. I reset thecomputer date/time so that the Perseus time-stamping is relativelyclose to the occurrence of the original recordings.After I get all this stuff digitized, I'll go over it for anyinteresting audio clips.Though the "VCR DX" method became known to the MW DX world about aquarter century ago, it is widely believed that, as far back as the JFKadministration, "spook" agencies such as the NSA were able to storesubstantial RF bandwidths for later review. Broadcast studio gradevideotape, or something similar but custom-designed, was used.Converters allowed any chunk of spectrum to be heterodyned to thebaseband range (0-3 MHz?) the tapes could accommodate. The late GordonNelson (WA1UXQ) seemed aware of it. Maybe some tapes will show up at aFort Meade, MD fleamarket / yard sale so we can tune around and hearstuff like Belize 834 and Bermuda 1235 once again, as well asMurray-the-K on WINS proclaiming his status as the Fifth Beatle.Mark Connelly, WA1IONSouth Yarmouth, MA>>
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