Thanks for that!
His design is at 144 MHz with values at 1000pF for C1, C2, and C3, and 56nH for
L1. Not sure if that would change, or which way, for 146.5. A formula out
there? Maybe the design just gets less gain as a consequence when up a bit
higher, but still works (that's ok).
But at $2 thats a worthy project. Yay!
If its no good at 146.5 then I have a cheapie LNA for 2m SSB. Then change some
values and try again.
I'll use a sequencer at some point ($30) and I wasn't impressed with the cost
of linears with preamps. A sequencer will handle this just fine. Much cheaper
than a linear or a big LNA, and essential anyway if using a linear. How many
Mirages out there have bad preamps due to RF sensing!?
It may be unfortunately true that upping a LNA on FM may just raise the signal,
but also the noise floor just the same. It might be my mobile and residential
noise floor is just high. If so, I'd rather build something cheap than run a
$120 LNA just to find that out.
Thanks!
Greg, K3RW
Get Outlook for Android<https://aka.ms/ghei36>
________________________________
From: Dennis Allen <N9TZL@outlook.com>
Sent: Thursday, December 12, 2019 7:22:32 PM
To: Gregory Winters <greg_winters@hotmail.com>; vhfcontesting@contesting.com
<VHFcontesting@contesting.com>
Subject: Re: 2m FM LNAs?
Greg:
I do not know what your level of construction skills are but you might at least
google this and see what you think.
Dennis Allen N9TZL
Simple Cheap MMIC Preamps Who needs a GaAsFET? Paul Wade W1GHZ ©2014
w1ghz@arrl.net
________________________________
From: VHFcontesting <vhfcontesting-bounces@contesting.com> on behalf of Gregory
Winters <greg_winters@hotmail.com>
Sent: Wednesday, December 11, 2019 6:58 PM
To: vhfcontesting@contesting.com <VHFcontesting@contesting.com>
Subject: [VHFcontesting] 2m FM LNAs?
I'd like to enhance 2m simplex abilities and pull in weaker SOTA activators.
Often times they hear me but I do not hear them. Increasing my antenna
capability would help (of course). But I can't run a beam mobile.
I'm looking for a reasonable LNA to pull out these weaker ones on 146.52, etc.
But many of the LNAs I see are for the SSB side of things.
Is there a LNA that I could use for FM?
Ideally I'd be able to use it mobile too. I run 65w on a 5/8s whip, seemingly
everyone hears me, but I struggle to hear some of them. The Kenwood 2m mobile
has an awful NF I guess, so I am hoping a LNA can help that.
Ideas?
Greg, K3RW
CN85ro
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