F/D ratio on KU dish

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Am considering purchasing the 76cm commercial quality KU dish from
babana.com; they indicate that it is better quality than Winegard's
DS2076.

The F/D ratio of the dish is 0.65, however the lnbf I would like to use
states a F/D ratio of 0.6

Is this difference considered a detriment to performance?
 
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First off, I'm no expert. Having said that, I'm at a loss as to why a
LNB maker or provider would specify a F/D ratio. I was under the impression
that the F/D ratio is a function of the dish size/shape/type, and refers to
the ratio of dish diameter to distance between focal point and LNB.
I use a DSS lnbf on a 84cm elliptical that was originally attached to an
18" offset. The main difference other than dish size and shape is the fixed
distance between the reflective surface of the dish and the lnbf. In theory
it would seem that a 3' prime focus dish would have a different F/D than
would a 3' offset dish. If in fact an offset dish is but a section of a
larger prime focus dish. I would also think that two offset dishes from
different manufacturers would have the same F/D ratio provided their sizes
are the same. In the end a difference of .05 in specs equals 1.5" on a 30"
inch dish. You may not be able to correct for that by moving the LNB in or
out from the dish in it's mount. Many folks get good results with "rigs"
that are less than precise. You likely will too.
Having never heard of babana.com, I went to their site to check it out.
I'll assume that the claim stating the dish(of unidentified manufacture) is
of better quality than the Winegard is self-serving advertising. The price
seems good, but what will shipping costs be? Where is babana.com located?
What's their phone number? I looked at the web site and couldn't answer
those questions. No one should have to send an email to get a phone number.
They may vary well be totally legitimate, but I advise caution.

Good luck
MH
 
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Thank you Mike for your scientific insight and especially thank you
for your
caution. Someone took a lot of time setting up the ws babana.com and
it
looked legit to me but on closer review, it appears to be a Vstore
type of marketing. They were prompt at answering my sales questions
but when I
asked a technical question, they have not responded (even though their
ws leads one believe that they have a tech staff). The Vstore type of
marketing is new to me and may just be a ws of sales people, who just
pass the order on to an unknown party.

"Mike Hedgepath" <mhedgepath@hotmail.com> wrote in message news:<2sjEc.936$LL5.111@bignews1.bellsouth.net>...
> First off, I'm no expert. Having said that, I'm at a loss as to why a
> LNB maker or provider would specify a F/D ratio. I was under the impression
> that the F/D ratio is a function of the dish size/shape/type, and refers to
> the ratio of dish diameter to distance between focal point and LNB.
> I use a DSS lnbf on a 84cm elliptical that was originally attached to an
> 18" offset. The main difference other than dish size and shape is the fixed
> distance between the reflective surface of the dish and the lnbf. In theory
> it would seem that a 3' prime focus dish would have a different F/D than
> would a 3' offset dish. If in fact an offset dish is but a section of a
> larger prime focus dish. I would also think that two offset dishes from
> different manufacturers would have the same F/D ratio provided their sizes
> are the same. In the end a difference of .05 in specs equals 1.5" on a 30"
> inch dish. You may not be able to correct for that by moving the LNB in or
> out from the dish in it's mount. Many folks get good results with "rigs"
> that are less than precise. You likely will too.
> Having never heard of babana.com, I went to their site to check it out.
> I'll assume that the claim stating the dish(of unidentified manufacture) is
> of better quality than the Winegard is self-serving advertising. The price
> seems good, but what will shipping costs be? Where is babana.com located?
> What's their phone number? I looked at the web site and couldn't answer
> those questions. No one should have to send an email to get a phone number.
> They may vary well be totally legitimate, but I advise caution.
>
> Good luck
> MH