Beam Approach Visual Indicator Ref 10Q/4 RAF

[toolsntat]

Good day to you all, my name is Andy and I'm wondering if you might be able to help me.
I have been directed to this forum as part of my quest to find out more about this Sangamo Weston Beam Approach Visual Indicator Serial No 13078G
All I know to date is from the Aero Antique website and just wondering how much more there is to learn?
Cheers Andy
I've tried pictures but perhaps I'm not allowed to post yet?

[longer ron]

This One Andy ?

https://cimg3.ibsrv.net/gimg/pprune.org-vbulletin/576x578/image_2021_12_31_145954_2dae63ceab618026aa88e5423eae45e73050 d991.png

[toolsntat]

Yes, thank you that's the instrument.
I have pictures of the reverse but cannot share yet.
Mine, or should I say, my other half`s (Christmas present from me...) looks in a used condition compared to that one. There is a little delamination on the glass and some rust etc. but it has the bulbs in position.
Cheers Andy

[longer ron]

Hi Andy
Yes not sure if you need a minimum number of posts before being able to post pics,I guess it will be maybe 5 or 10 posts.
Without googling I cannot give any info about the system although I have a rough idea how it worked.
Hopefully somebody will come along with some useful stuff for you.

rgds LR

[toolsntat]

Ok, thanks LR.
That Aero Antique website has given me a good idea behind the theory of its use.
The million dollar question for me is if it's possible to trace the history of this specific instrument back any further ?
Iim under the impression that a good many would have been made and fitted. Perhaps in the intervening years studies and notes have been made that might give me a clue of it's past ?
Cheers Andy

[chevvron]

Roughly, the 'beam' transmitted a radio signal consisting of dots to one side of the on course signal and dashes to the other side.
If you were right of course, you would receive dashes which meant drift left; if dots you must drift right.
As you got close to the beam, the dots and dashes would merge to become a continuous tone so you were on course.

[toolsntat]

Thank you Chevron.

[longer ron]

Hi Andy
Some nice old 1945 Weston Aviation Instrument Adverts and company info in 'Graces Guide'

https://www.gracesguide.co.uk/Sangamo_Weston

[toolsntat]

That's a nice look into the history thanks.
Interesting to see they describe it as a Blind Approach Indicator.
This little titbit makes me think that at the time of use and the aircraft it was fitted in it's likely there wasn't any landing lights.
Cheers Andy

[India Four Two]

Can someone explain how this instrument converted the audio signal to a needle presentation?

[longer ron]

Interesting to see they describe it as a Blind Approach Indicator.
This little titbit makes me think that at the time of use and the aircraft it was fitted in it's likely there wasn't any landing lights.
Cheers Andy

I think in this case 'Blind Approach' just means 'Non Visual Approach' - ie in bad weather or at night to get the aircraft safely down the glideslope until hopefully eventually being able to land visually when descended to under cloudbase or visual with any Airfield/Runway Lighting/Funnel Lights/Drem Lights etc.

[megan]

Can someone explain how this instrument converted the audio signal to a needle presentationIFT, this might help.

https://en.wikipedia.org/wiki/Low-frequency_radio_range

[chevvron]

You may find further details in www.airfieldresearchgroup.org.uk under RDF/Radar sites sub section 'SBA(Standard Beam Approach)'.

[India Four Two]

megan, thanks for the link. I had looked at various wiki pages, but I didn't think to look at the radio range page. I hadn't heard of the vibrating reed instrument before but this is not the same as the SBA instrument.

chevvron, can you post a link? I couldn't find the section you referred to.

[chevvron]

megan, thanks for the link. I had looked at various wiki pages, but I didn't think to look at the radio range page. I hadn't heard of the vibrating reed instrument before but this is not the same as the SBA instrument.

chevvron, can you post a link? I couldn't find the section you referred to.
Unfortunately the forum is copyright protected so links don't work and you have to dial in to get the info.

[megan]

IFT, try this. On the dial pictured the two circular features are lights which light up when the aircraft passes over the relevant marker beacon during the approach, the "O" being the outer marker and the "I" the inner marker.

https://wiki2.org/en/Lorenz_beam

[India Four Two]

megan, here’s the section of the page you referenced that I’m interested in:
In order to ease the workload, Lorenz later introduced a cockpit indicator that could listen to the signals and display the direction to the runway centerline as an arrow telling the pilot which direction to turn.

I am trying to find out how the indicator converts the audio A and N into what amounts to a Localizer signal.

chevvron, my problem is that I can’t find the section you quoted. Starting at the Home page, how do I drill down to the info?

[chevvron]

megan, here’s the section of the page you referenced that I’m interested in:


I am trying to find out how the indicator converts the audio A and N into what amounts to a Localizer signal.

chevvron, my problem is that I can’t find the section you quoted. Starting at the Home page, how do I drill down to the info?
!) Select 'Forum' on the header.
2) Select 'Forum Members area'. (you can sign on quite quickly if you're not already a member)
3) Page down to 'Airfield related infrastructure and associated equipment'
4) In this section select 'RDF/Radar sites'
5) From the list of threads, select page 3
6) On page 3, select 'SBA (Standard Beam Approach')
NB: If you're not already a member, it can become VERY addictive!!