Following results of investigations by Alex Pettit were posted on SARA Mailing List 20/1/2026:
The “Nooelec 1.4GHz” feed seems improperly designed : the Focal Point of a 1m f/D 0.35 dish is 35cm (with a small variation from that depending on feed design). For some unknown reason the dipole on the Nooelec 1.4GHz feed is positioned way beyond that .
Try positioning the mid point of the black enclosure ( location of the dipole ) at 29cm from the dish
An Excellent High Performance Upgrade for the Nooelec 1.4 GHz system is to replace the Nooelec feed & LNA with the Kraken Discovery Dish Feed & LNA (~$120 )
https://github.com/AP-HLine-3D/HLine3D/blob/main/21cm_Step1b_KrakenDiscoveryFeed_Eval_05.pdf
On Tuesday, January 20, 2026, Conrad Cardano responded to above:
I did lower the feed by 4” to coincide with the focal point of the parabola.
It does perform much better.