Since I will be using only half of the LNB anyways, perhaps it will make no difference whether I use an LNB designed for a 75e or one designed for a 60e provided my LNB support stem length is correct.
I believe you're on firm ground, there.
Some years back, one of the members documented a way to calculate the distance between two LNBs, given a particular dish, and any two satellites.
A main consideration was focal length of the dish.
- For DBS, DishNetwork needs 9° spacing for 110° and 119° satellites.
The Dish 500 assembly handles the task.
Since DBS is far less critical, this dish works from coast to coast.
Unfortunately, the dual LNBF monoblocks designed for FTA are more critical and a bit of a trade-off
- For two birds at 4° spacing, SatelliteAV came up with a dish, custom bracket, and small LNBFs to do the job.
- Say you want two birds at 2° spacing.
Need little tiny LNBFs and a long focal length dish (1.2m is good).
- Or, given a big, long dish, let's say you wanted to cover the sky...
There's at least one project with a slew of LNBFs on a 6' Prodelin dish!
reading material:
MJflash and his math to put two LNBs on a single dish:
http://www.satelliteguys.us/free-air-fta-discussion/89049-offset-lnbs-theory-practice.html
WescoPC and 2° birds on a 1.2m dish:
http://www.satelliteguys.us/free-air-fta-discussion/151258-building-1-2-meter-dish-2-spacing.html
Linuxman and entire arc on 6' Prodelin:
http://www.satelliteguys.us/free-ai...st-way-receive-whole-ku-arc-fixed-dishes.html
Mike Kohl does Skyvision wide-swath dish:
http://www.satelliteguys.us/free-air-fta-discussion/181923-whats-new-skyvision.html