Eval : Kraken 1420MHz Discovery Feed & 1m WiFi Dish :

[Alex P]

An Evaluation of the Kraken 1420MHz Discovery Feed on a 1m WiFi Grid Reflector Dish 

Exec Summary :

      Impressive Performance from a " Near Off The Shelf " H-Line Radio Telescope

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

[JERRY TAYLOR]

Hi Alex.  How does the Discovery dish feed on the grid antenna compare to others scopes you have tested?

Jerry Taylor 

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[b alex pettit jr]

This will give you an idea ..

Considering Cost and Build Simplicity, IMO its a Winner.

Alex

[JERRY TAYLOR]

Does that line above the graph represent over 3db signal strength?  If so 🤯!

Do you have more test results to come!

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[b alex pettit jr]

The 1.2m dish mod tops out at 2.68 dB over Sky

The plot below represents a Lot of Work . 

I'll add the Kraken Disco..

On Friday, December 26, 2025 at 01:06:11 PM EST, JERRY TAYLOR <gfaj...@gmail.com> wrote:

Does that line above the graph represent over 3db signal strength?  If so 🤯!

Do you have more test results to come!

[b alex pettit jr]

The plot below represents a Lot of Work . 

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

[Robert Meade]

Does anyone have all or at least some of these feeds with the 1.5m solar cooker dishes and could compare the discovery feed against the common loop and cantenna feeds with such a setup? I only have discovery feeds with my solar cooker dishes.

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[b alex pettit jr]

The most significant performance spec of the Kraken LNA/Feed is its Stability over time/temp

That is the result of the close soldered connection of the 1st LNA Transistor to the Antenna element

Apparently Micro_Ohm changes in cabling or connectors between the feed and LNA  over time or temp cause significant level shifts.

This Design, either through intent or good fortune does Not.

[b alex pettit jr]

IF properly positioned, the Loop, Cantenna, and Kraken will have nearly Identical Performance .. 

You may gain a few tenths of dB with the lower noise figure of the Kraken, but it will not be Huge.

The main takeaway   is :  its " NOTS "  :  Near Off The Shelf

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[Robert Meade]

That was my thinking. It appears you've shown that with dishes of similar f/D, the krakenRF discovery feed doesn't have issues with pattern shaping. Did you publish the NEC model of the feed somewhere?

[b alex pettit jr]

I never made an NEC model of the actual "Feed" as it is some ( unknown ) complex Patch .

I just modeled a simple Dipole .. it does not tune well & there is complex interaction between the Dipole <> Reflector spacing .. 

BUT, it its Overall Performance is Valid 

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[Ayushman Tripathi]

Hi Alex,

What do you think about a Discovery Dish feed vs. a Cantenna on a 2.5-meter dish, based on your analysis?

I've built my Cantenna and will be setting it up on a 2.5-meter dish next week.

Thanks

[b alex pettit jr]

The Discovery Feed is a great off-the-shelf solution . 

The Tuned Cylindrical Waveguide AKA Cantenna has bandpass properties that may improve your results in a high RFI environment

Alex