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By: - 9th September 2010 at 04:36 Permalink - Edited 1st January 1970 at 01:00
Anyone?
By: - 9th September 2010 at 08:02 Permalink - Edited 1st January 1970 at 01:00
OK, the reflector is a double parabolic, it is wider than it is high. I can get the measurements plus pictures possibly today, if not then I can certainly get them on Saturday. We have a bullet with the radome removed in the museum.
By: - 9th September 2010 at 08:34 Permalink - Edited 1st January 1970 at 01:00
About 21" wide according to my measuring tape.
Anne
By: - 9th September 2010 at 09:03 Permalink - Edited 1st January 1970 at 01:00
i'd go with the above from memmory !! i have a photo on my old hard drive ( not accessable as yet ) it is of the full removed unit ( on display at the science and industry museum in manchester !! )
By: - 9th September 2010 at 21:07 Permalink - Edited 1st January 1970 at 01:00
Thanks, Peter, anneorac, & tornado64.
Having not gotten an answer here, I asked on PPRuNe last night, and got this from a chap calling himself "radar101":
I've just been up in the loft with a tape measure to find my dish:dish width is ~53 cm / 21 in
dish height at the join between the 2 reflectors is ~48.5 cm / 19 in
The reason for the 2 halves is that although it was amplitude comparison monopulse in the vertical plane, it was phase comparison in the horizontal plane - the L-R feed horns thus needed to be about 3 ish wavelengths apart.
And rhajaramjet said
The dish was in reality two parabolic reflectors joined along the vertical edge. It was a V clever arrangement; with the four-horn feed (split two to each half of the reflector) it transmitted (at 8,500MHz - 9,000MHz) four overlapping lobes which allowed the radar (unlike contemporary conical scan radars) to use sum and difference signals to angle track from a single pulse.
And now you've confirmed the correctness of his measuring (not that I had any doubts).
By: - 10th September 2010 at 23:16 Permalink - Edited 1st January 1970 at 01:00
Lightning Radar
Go It Mills sort them out.
might I ask why you need the details on the reflector. The 4 way feed in the middle is much more interesting.
You need a PhD in microwave engineering to get your mind round that.
I did my barrier at 30mu on 23 quite challenging was that!!!
jb154
By: - 11th September 2010 at 02:14 Permalink - Edited 1st January 1970 at 01:00
A friend was looking at material on the SR.177 and noted that it said it was to have A.I.23 with an 18" reflector, and he began looking to see if this was the same as on Lightning or different.
All he could find mentioned the proposal for a modified Lightning with a reflector of 27"... and on a thread on the Secret Projects board a poster claimed the production Lightnings had a 24" reflector.
This seemed a bit large to him, and thus the question.
As a general rule, the larger the reflector diameter, the longer the range of the set, and the better the sensitivity becomes.
Thus, if the SR.177 had a smaller reflector, it would not have been as capable of conducting a radar-guided intercept as the Lightning.
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By: Bager1968 - 8th September 2010 at 03:28
The question of the diameter of the reflector dish for the A.I.23 in the Lightning has come up with a friend.
He ran across a mention of 24", and would like to find out the correct diameter.
As I know a couple of you could "just pop out back and measure the thing", I thought I'd ask here.
;)