kd0ar at sbcglobal.net
Sun Aug 31 09:59:33 PDT 2008
A recent post mentioned the need for a preamp. This reminded me of something I want to share with the group.
Station here consists of an FT-817ND and an FT-857D. The 817 is pretty sensitive on UHF, but the 857 is a little lacking in comparison.
I was looking for a preamp online that would help, especially with the 857. I went and ordered a Ramsey PR40. I figured for $15 I couldnt go wrong. Although its not a GaAs device, (its a bipolar), it works pretty well. I actually didnt want a GaAs because I was afraid of blowing the device anyway, being I'm running a homebrew "Arrow style" antenna on a fixed elevation mast, and the 144 MHz leakage getting into the preamp would probably blow the device the first time I keyed.
I am not using any TR switching on the preamp. (I only work the FM birds at this time).
After building the kit, I put it up, worked a pass on AO-27, then goofed and sent 432 TX energy up the line, blew the amp. I ordered replacement transistors from MCM for $.52 each!
Although I cannot measure noise figure, it specs at 1dB, 15 dB gain. I know it makes a HUGE difference on my end. Satellites that were noisy before are now full quieting and armchair copy
I have found this item a very cost effective solution. I wanted to share this experience with the group. I'm just pleased with the preamp and of course, receive no personal gain by recommending this product.
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