Geodesic Parabolic Dish Antenna

[Yoshiyuki Takeyasu]

Hi,

Recently, it’s been a popular trend to repurpose inexpensive solar cookers into parabolic dish antennas. However, don't you find their weight makes them a bit difficult to handle?

I’ve just updated my design chart for a Geodesic Parabolic Dish Antenna that is both lightweight and easy to DIY. Please feel free to give it a try:
http://www.terra.dti.ne.jp/~takeyasu/GeoParaAnt_9.pdf

You can see the final version of frame structure in the photo below.



I’ve received a report from a German radio amateur who successfully built a 2-meter dish using this specific structure:
http://www.terra.dti.ne.jp/~takeyasu/1753204419672.jpg

I hope my design charts prove useful to your projects!

Regards.

Yoshi Takeyasu
JA6XKQ

[Alex P]

Hello Yoshi,

Very interesting .. 

Have you ever tried a deep dish ~ f/D 0.25 ?

How close is the dish to a Parabolic vs a Spherical surface ?

Regards,

Alex Pettit

[Yoshiyuki Takeyasu (JA6XKQ)]

Hi,

I have never tried f/D=0.25 because, in principle, this design is not suitable for deep dishes. This dish antenna is not a spherical, so-called "geodesic dome." Instead, it features a structure where the ribs are formed by geodesic lines—the shortest distance between two points on a parabolic surface. Please refer to F4BUC's numerical analysis regarding surface precision at the following URL: https://qsl.net/f4buc/precision_surface.htm

Regards.

Yoshi Takeyasu

JA6XKQ

2026年1月14日水曜日 0:15:05 UTC+9 Alex P:

[b alex pettit jr]

Thank You.

If you want some baseline against which to compare your system, 

here is a recent eval I performed with a 1m f/D 0.35 dish .

https://github.com/AP-HLine-3D/HLine3D/blob/main/21cm_Step1b_KrakenDiscoveryFeed_Eval_05.pdf

Y axis : dB vs Cold_Sky    peak ampl @  Declination + 40 dg RA 20:30 hrs

=========================================================

'numerical analysis' is useful as a basis for building the structure, 

BUT, the actual physical shape of the dish needs to be validated.

Regards,

Alex Pettit