Does anyone know what microwave frequency was used by the Premier Channel in the mid 1980's to broadcast HBO in the SF Bay Area?
The reason I need the info is because I can obtain some of these old microwave dishes and want to try them on WI-FI if the frequency is OK.
Please reply if you have info, TIA
Didn't find your answer? Ask the community — no account required.
A
Adair Witner
The gain of the dish is going to be proportional to the size and freq that it's used with.
A 3' would work just as a 30' dish would except the gain and directivity of the 30' dish would be more. Now there are things like feed point distance and inpedence that would also play into the efficency of the dish but what it all comes down to is how you feed it and if you plan on using the horn that's on the dish or build your own.
My guess(tm) is that they used the MMDS frequencies from 2.5 to
2.7GHz. There was also a band at 2.1GHz for TV distribution. As I vaguely recall, the feed had an RF amplifier and downconverter inside, which probably will need to be "converted" to 2.4GHz to work. Something like this article: |
formatting link
|
formatting link
Also, please note that the maximum gain from a 0.6 meter diameter dish antenna is about: gain = 9.87 * Dia^2 / wavelength^2 * (feed efficiency) gain = 9.87 * 600mm^2 / 125mm^2 * 0.4 gain = 91 dBi = 10 log(91) = 19.5dBi The 40% efficiency (that's the 0.4) is probably optimistic. I don't know the exact size of the STV dish, but I suspect it's close.
Join the Discussion
Have something to add? Share your thoughts — no account required.
Didn't find your answer?
Ask the community — no account required
Report Content
You are reporting this content to the moderators. They will look at it
ASAP.