BaMaTech DuoBand-Feed: receive poor?

  • Than you need to remove the lense, otherwise you under-illuminate your dish...


    According to the BamaTech description: "The 10 GHz horn, as supplied, lights a mirror with f/D of 0,4 almost optimal."

    Peter Gülzow | DB2OS | AMSAT-DL member since 1983 | JO42VG

  • The 'Bamatech Horn' is actually an 'open' waveguide, so suitable for f/D's up to 0.45. When having a f/D > 0.45 the waveguide needs 'some focussing' to illuminate the dish so that the -10 dB points of the lobe coincide with the (horizontal) edges of the (offset) dish. Either a horn or dielectric lens may be a solution. (such as developed and deployed in zillions of broadcast LNB's ; -)

  • DD0KP


    Hi Heiner, i believe i have been very clever and buy a Venton EXL-T Rocket Twin LNB, the only problem is this type don´t fitt to the Bamatech Duo Feed. Also i still wait for the lense of Bamatech itself. Have ordered and paid about 14 Days ago. If this parts arrived here i like to compare the Bamatech Duo Fed against the GM 201 wich produce a very good signal, but the Bamatech doing realy poor until now.

    If you get lenses from Venton wich fitts to the Bamatech i´m interested to buy one from you.


    73 Joachim

  • I used a lens from an Inverto Rocket LNB it fit perfekt on the BaMaTech Patchfeed. When I compared the lenses on my, now used, Potty Feed the Venton was a bit better than the Inverto one but as it fit so perfekt I let it on the BaMaTech. See Picture below. I have the first version on the BaMaTech with SMA plug for the 10GHz, attached is modified GM201.


  • Die Original Bamatech Linse für den Duo Feed ist jetzt eingetroffen.



    Ansicht auf die Innenseite



    Die Linse von dem nicht passenden Venton EXL-T Rocket Twin LNB habe ich wieder mit dem LNB zusammengefügt.


    Als nächstes werde ich die Original Linse auf das Duo Feed aufsetzen und danach eine erneute Messung durchführen.

    Den Vergleich Duo Feed ohne und mit Linse werde ich hier dokumentieren. Ohne Linse war der Empfang am 85 CM Offset Spiegel nicht brauchbar.


    Den im Verhältnis teuren Venton EXL-T Rocket Twin LNB werde ich auch testen und das Ergebnis hier mit einfügen.