AMSAT-BB Users..... Just so you know, many E-Mail Spam Filters send messagesthat have the title "No Subject" directly into the Spam Foldersince there are so many Phishing Scams that use messageswithout titles. So, if you want a lot of people to actually SEE your messages,then you always need to give them a TITLE. :-) 73, Bob K8BL
From: Zach Metzinger zmetzing@pobox.com To: amsat-bb@amsat.org Sent: Thursday, September 1, 2016 12:17 PM Subject: Re: [amsat-bb] (no subject)
On 09/01/16 11:01, jeffory broughton wrote:
I have had several FT 847 radios.Great low cost choice and works well with satpc32.However ,for just a few dollars More get a used IC910. Much better rx sens with a lower noise figure.Also REAL DNR circuitry.Make listening for long periods a pleasure,not so exhausting. Also if you compare the specs of the IC910 and IC 9100 uhf and vhf SECTIONS, you will see they are IDENTICAL!
I wouldn't focus on noise figure at the receiver, unless you happen to have 1' of cable between the rig and your antenna. Instead, I'd put a bias-T-powered LNA at the antenna to preserve your SNR (Friis formula).
Having recently built a U310-based LNA, I can say that a single night's work of soldering and testing pays off well. Total parts cost was in the $5 range.
I plan to build a new LNA based on a pHEMT just for fun. Only a couple of bucks from Digikey. Why settle for 1.0dB when you can potentially get 0.25dB! :-)
--- Zach N0ZGO _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb