On 22 Apr 2009 at 21:17, Yokshs wrote: > Hi all, > > Well, I finally did it. I let the smoke out of my Icom AG-35 preamp! > > I've read several such messages on the list over the years. Glad to know I'm > not alone in this club.. hi hi > > Before I replace the 3SK121 with an identical unit, I wonder if anyone has > used a similar FET with better NF? The AG-35 specs I found stated 1.5 dB NF > and 15 dB gain. > > I went through my collection of new parts and found a few Agilent ATF 54143 > hemt.. > > The NF on similar designs is more like .38 to .5 dB and gain is 19-22 dB. > > I wonder if anyone else has had the wild idea of rebuilding their preamp? > I'd like to retain the enclosure and relays, etc. > > Several 54143 designs are available, such as this one: > > http://www.qsl.net/yu1aw/atf54143eng.htm > > Thanks for any help or ideas. > > 73, > > Kyle > K0KN > I fried my UHF one too...I order a couple from ICOM. With my very limited electronics building skills i cut the dead one leaving as much legs as possible and i resolder the replacement over the cut legs. Not elegant but quick and effective. Is this is achieving the same overall previous gain figures? that i don't know but it works.
I have another one to replace in a different type of preamp but the FET is below a lot of other components and he's flat mounted (No legs) i don't come up with a solution with this one? "-" Luc Leblanc VE2DWE Skype VE2DWE www.qsl.net/ve2dwe WAC BASIC CW PHONE SATELLITE _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
