Re: Simrex - GLB Pre-Selector Pre-Amplifier
> Jack Chomley <ra...@...> wrote: > Well, I have decided to buy and try a Simrex > Pre-Selector,experiment with it, test it > .......whatever. Something to never say in an airport... "Hi Jack", Hopefully you will find the Simrex / GLB Pre-selector to be a very interesting and useful box. There are multiple stages of filtering in front and behind the active device. During the earlier posts I tried to highlight the difference between the additional filtering although I didn't (want to) go into much detail about at least one under-played advantage of having post filtering stages after the active device. If we were to actually compare the pre-filtering against a high Q band pass cavity, you will see a different shape band pass due to a single cavity versus a multi-stage layout. You could and most likely would see a lower loss similar shape if you had two or more series high-Q band cavities in front of an external RF-Amplifier (not even addressing the post filtering). A real world question ... is the size, cost and hardware complexity of the High-Q Cavities with a separate RF Pre-Amplifier configured in the same layout as a Simrex / GLB circuit going to yield a major advantage in your specific application? Will the Simrex / GLB Pre-selector provide a benefit to your system? In many of my personal experience examples using a GLB Pre-selector has clearly improved the receiving system performance. > At the very least I will learn something from my experiences > and it may end up being useful to me, anyway. It's nice to read that you're willing to make the effort and spend money for the education. I expect you won't be disappointed with your Simrex unit. > I certainly appreciate the different points of view here > and have learned of alternative methods and the reasoning > behind them. The jackpot of knowledge... and you weren't even in a Casino. > For me, all of it is good information :-) > 73, > Jack. VK4JRC Cheers Jack, s. > Sent from my Apple iPad Tablet PC Response sent from a painfully slow dial-up internet connection.