'Telemobiloscope' (aka RADAR) WW-1 Style

[Daryl J.]

Would it be too far off to have a box with vacuum tubes on the top, a cooling unit,  and antenna tubes supported by rigging wires?    Another antenna idea is a main rod  slung underneath either the fuselage or both wings with smaller rods protruding from the sides.   It would be significantly larger in size than either the Yagi antenna or German antennae of WW-2.  The viewing screen might be a translucent green plastic bead of approximately two hand spans in size in a brass bezel of some sorts.   And yes, the plans include a round multi function display as well in a suitable location.   

I'm completely disfamiliar with the history of radar but want to put a rudimentary unit into an alternative Wingnut Wings Bristol Night Fighter as some sort of Defense of the Very Damp Rock machine dedicated to destroying Gothas and Zeppelins in the dark.     The idea goes back a couple of years for me, but the release of the New Zealand Brisfit brings it all to the fore burner. 

Cheers, and TIA,
Daryl J.

[frank2056]

According to that infallible source of information, Wikipedia, using radio waves to detect objects has been around since 1904. So Whiff away!

[Daryl J.]

Thanks.   I rarely use that site and hadn't thought of it.



Daryl J.

[Spey_Phantom]

i would love to build such an installation and then fit it onto a vicker Vimy bomber.
do i hear someone say "The Great War GB" 

[Hobbes]

The antenna size depends on the frequency that is used. Since radar uses short wavelengths (in the order of 1 cm) you don't need huge aerials. A larger antenna would give more gain, which would help range.

the first radar wasn't that large:



That system didn't have a radar scope, which simplified construction. I'd expect a usable ca. 1900 radar to have a huge cabinet filled with radio tubes to process the data,

[Daryl J.]

Hobbes!   Thank you for that photo!!!   


Daryl J.


[Edit]  PS:  Whoever changed the title of the thread, I like it.   A lot, actually.       After clicking on Hobbes' link and seeing the German word, it just seemed fitting for the machine.

[jcf]

Vacuum tube on Wikipedia, the history section should be helpful:
http://en.wikipedia.org/wiki/Vacuum_tube

RCA 808 power tube


Jon

[jcf]

Don't forget acoustic location:
http://www.dself.dsl.pipex.com/MUSEUM/COMMS/ear/ear.htm

[Doc Yo]

The antenna size depends on the frequency that is used. Since radar uses short wavelengths (in the order of 1 cm) you don't need huge aerials. A larger antenna would give more gain, which would help range.

the first radar wasn't that large:



That system didn't have a radar scope, which simplified construction. I'd expect a usable ca. 1900 radar to have a huge cabinet filled with radio tubes to process the data,

  Radar uses shorter wavelengths, now, Hobbes, but it wasn't always so...for instance, from the very article
you cite:

His 'telemobiloscope' operated on a wavelength of 40-50 cm.

And if memory serves,
one of the reasons the Germans were still using the awkward, draggy 'Staghorn' antennas was their belief that
radar wouldn't work effectively at the shorter wavelengths...

Anyway, the idea of a WW1 radar equiped Night fighter is pretty neat, especially given the chosen platform.
I'll offer the suggestion of giving it a third wing, and making the strutwork of the upper wing double as the
radar antennas. Good luck with the build in any event.

[PR19_Kit]

Don't forget acoustic location:
http://www.dself.dsl.pipex.com/MUSEUM/COMMS/ear/ear.htm

I saw the two Greatstone sites in Kent this last weekend, they are GINORMOUS! 

[Hobbes]

  Radar uses shorter wavelengths, now, Hobbes, but it wasn't always so...for instance, from the very article
you cite:

His 'telemobiloscope' operated on a wavelength of 40-50 cm.

Fair enough, but with a wavelength of 50 cm, the antenna prongs need to be 12.5 cm long (iirc). That's doable for an aircraft.

[Daryl J.]

12.5 cm per prong?  Can they be in multiples of 12.5 per prong?   12.5 cm =.39 cm in 1/32 scale.

TIA,
Daryl J.

[Jeffry Fontaine]

12.5 cm per prong?  Can they be in multiples of 12.5 per prong?   12.5 cm =.39 cm in 1/32 scale.

Daryl,

You should be able to create a Yagi type antenna which was the original antenna design for the early RADAR sets.  this could be in the vertical plane or the horizontal plane or both in an "X" shape along the axis of the antenna with the individual dipoles jutting out from the central shaft or boom of the antenna.  As the frequency increases the dipoles become shorter so your WWI era antenna would have dipoles of the length you have quoted above which should be sufficient for a WHIF. 

Wikipedia entry for "Yagi Antenna"
Satellites, Antennas and HDTV
Google image search for Yagi Antenna
Google web search for Yagi Antenna
tpub.com page on "Multi-element Parasitic Array"
tpub.com page on Yagi Antennas
radio-electronics.com page on Yagi Antennas
Home made UHF Yagi Antennas

Alternatively you could try to create a log periodic antenna (think of the outside television antennas mounted on the roof) which would look interesting. 

[NARSES2]

Don't forget acoustic location:
http://www.dself.dsl.pipex.com/MUSEUM/COMMS/ear/ear.htm

I saw the two Greatstone sites in Kent this last weekend, they are GINORMOUS! 

I've been there Kit, they took my breath away they were so much bigger then I expected

I now have an image in my head of a Brisfit we the a back seater with hands cupped over huge ears, rather like one of the kids from "Bash St" or maybe a trained elephant  I'll get my coat now.