At 12:29 PM 4/2/2008, Nate Duehr wrote:
On Mar 31, 2008, at 2:11 PM, John W Lee wrote:
I have an FT-847 with the good internal preamps. The ARR SP432VDG even makes this setup BETTER! I use both the internal and SP-432VDG. Signals are mostly VERY good. Also use a 20 element beam on the downlink.
For those interested, there was a nice discussion of how to calculate the noise figure of cascaded pre-amps on the Repeater-Builder mailing list about two weeks ago.
The postings should be pretty easy to find in the RB list's archives at YahooGroups.
If you're not interested in Repeaters, you can always join a YahooGroup (if the list is on YahooGroups) and set your preferences to "no e-mail", so you can read list archives, look in the Files area, etc.
-- Nate Duehr, WY0X [email protected]
OR...you can click on this link to my website for a spreadsheet that calculates noise figure, noise temperature, and MDS for three cascaded stages. The whole spreadsheet which will calculate eme path-link performance for two stations. But the first section deals with calculating noise figure.
http://www.kl7uw.com/emelink.xls
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