Jump to content
The Education Forum

Chris Bristow

Members
  • Content Count

    462
  • Joined

  • Last visited

About Chris Bristow

  • Rank
    Advanced Member

Profile Information

  • Gender
    Male

Recent Profile Visitors

2,770 profile views
  1. I am open to the possibility that the shot came from the covered truck sitting on commerce visible in the Z film. That makes the commerce location more viable imo. Another wrinkle is the bullet would tip downward from impacting the windshield. Adding that to the parking lot trajectory may put it all the way down to the sidewalk as David Lifton has surmised. I don't know exactly how he got to the sidewalk. It could be the bullet tipping down or slightly different measurements of windshield hole to throat or both. The tipping bullet may be inescapable but that is just based on reading some exp
  2. I base JFK's sitting posture on frame 209 when you can see the very top of his head and fr 225. I estimate the throat to be 3.5 ft off the ground. I don't remember off hand the height of the bullet hole but the throat to windshield hole trajectory does lead to the annex parking lot. But if you take into account the bullet tipping down a bit from passing through the windshield then maybe you are back to the sidewalk on commerce. It all comes down to exactly how we estimate trajectories from measurements of photographs. Realistically it is possible to have come from the South knoll and created t
  3. If the slope of Elm and the slope from windshield to JFK are equal and opposite they cancel each other out and the line from windshield to JFK becomes level. That means the shooter would have to be at the same hasl as JFK for a level shot. His throat was about 424ft hasl and the annex parking lot is 424 hasl as is the overpass. But now I think I must have made a basic mistake. The slope of the limo was lessened by facing 45 deg to the Southwest at fr 223. That should steepen the angle from windshield to throat not lower it. The result would be to raise the shooter position not lower it do
  4. Once I calculated the vertical trajectory from JFK's neck, and through the Bullet Hole next to the rear view mirror. It came to the parking lot of the terminal Annex Building. Someone crouching there could have made the shot. I heard David Lifton has calculated the shot coming from the sidewalk that goes under the triple underpass. So I rechecked it and found I made a mistake. I used the three and a half or four degrees slope of Elm Street to put the shooter in the terminal Annex parking lot. But the limo was not facing straight down Elm, the road bends to the left and it was actually at a 45
  5. Chris, no I haven't mapped out the limos movements prior to frame 312. The distance it travels on Elm from 312 up to 323 seems to be consistent with JFK's head lining up at 323. So it seems to be 6° off from 312 up to 323. I have noticed in the past that in Alt6 the line of sight through the limo has it pointing five or so degrees to the right. But of course the photo shows it is straight and lines up with the lane markers. So I have assumed in the past I just made a mistake. But the window alignment in 312 can't be a mistake. So I'll take another look at it alt 6.
  6. Every reference to the trajectory of the head shot at 313 has the limo aligned and pointing straight down Elm parallel to the lane markers, and the Nix film verifies JFK's head was at a near perfect 90 degree angle to Zapruder's camera at 313. But the Z image at 312 shows Zapruder was not perpendicular to JFK's head. In fact it isn't until about frame 323 that Zapruder is perpendicular to the backseat. In the graphic on top the red lines of sight show Z's angle to the limo that the nix film verify and the X on Elm St show to be the location of JFK's head at 313. JFK's head and the
  7. The tape being activated by sound is a new wrinkle for me. To the researchers that have been examining the tape far deeper than I have a question. Can we rely on the timing between the shots and the sirens being separated by at least 3 minutes?
  8. The graphs shown in the wave pattern in the HSCA video have the middle of the range at 2.0 khz. A police siren is supposed to be around 1.8 khz and if the siren was approaching at 80 mph the doppler shift would increase it to a bit over 2.0 khz. As the siren pulled away it would drop from 1.8 to 1.6 khz. There are dopper shift calculators online that make it pretty simple to calculate. Regardless of the speed of the vehicle/siren the middle of the doppler shifted range should be around 1.8 khz if was recording it accurately. If it comes out that way I would be fairly confident the measured
  9. I would love to see the wave forms again. My old mac with my wave form program that came with it"Garage Band" died long ago. I don't know how much filters would effect this measurement but I would like to see how much doppler shift happened as the motorcade approached then passed the open mic. If filters don't reduce the effect it may show how fast the motorcade approached. If it exceeds 70 mph it would indicate the motorcade was on the freeway.
  10. I do wonder if it is possible that 2 mics were getting stuck off and on during the event. As to the belt recording more than one mic at a time, it does happen. When I worked in a job that used radios we could often hear the open mic and a faint sound of a second mic trying to get thru. When a mic is keyed and the dispatcher can't get thru it to tell the driver the dispatcher ups the gain a lot and then even with the mic keyed the driver can hear the dispatcher tell them to check their mic. Imagine you are saying something very embarrassing and confidential yet 30 other drivers and dispatch
  11. Here is a portion of the HSCA testimony and at 49:30 they address the issue of the sirens Some interesting points made here. The congressman notes that the sirens happen 3 minutes after the gunshots and asks how that is possible. The answer is the mic would not have picked up Curry's siren at the start because it was to far away and just beyond the underpass. But the first siren was the follow up SS limo. Kinney stated as soon as the head shot happened he hit the siren and made a radio call. So the question is still open because Kinney was more like 250 feet away and not beyond the overpass
  12. For what it's worth it seems to be running about 2300 RPM through almost all of the recording. Then it slows down just before the head shot which is consistent with McClain story about coming to a stop on Houston at Elm Street. I think the biggest clue is those sirens that pass by whoever had their mic open. As I recall that happens 30 seconds or more after the shots. That should speak volumes about the location of the bike in question. Since we hear the sirens approach and then pass by the open mic I have to wonder how that could ever be McClain. How could he be in a position where
  13. The dispatcher not only identifed the motorcycle as a 45 cubic inch trike. He and McClain also identified the whistling of the person riding that bike. So there's no doubt as to which 45 trike it was, and that person was apparently positioned out by the Trade Mart at the time. There is a sound of sirens and they sound like they approach and pass very close to the trike. Then they Trail off. The sirens are of multiple Vehicles traveling together.
  14. I know there are filters that will take out the high-end and such but I am not looking at the frequency of the sound. My judgment of it is based on the pattern of sounds. The repeating sound of the two motorcycles have a different Cadence. Consider the drumming in that Van Halen song. The frequency of course is nothing like an engine. It is simply the Rhythm of the drumming that instantly allows you to recognize that he's imitating a Harley 74. Years ago I used to radio at work and seems feasible to me that a dispatcher would know the difference sounds of different drivers bikes.
×
×
  • Create New...