Hi George, KA3HSW The 3SK121Y is a Dual Gate MOS-FET in package SOT 143R and it can be directly replaced by the very inexpencive BF998R with same package
See the cross reference here: http://www.go-ic.cn/admin/newspic/20061127185602infineon.pdf The Noise Figure of the BF998R is 1 dB at 800 MHz See the data sheet here: http://www.nxp.com/documents/data_sheet/BF998.pdf I hope this helps. 73" de i8CVS Domenico ----- Original Message ----- From: "George Henry" <[email protected]> To: <[email protected]>; "Mark L. Hammond" <[email protected]> Sent: Thursday, March 18, 2010 4:54 AM Subject: [amsat-bb] Re: Devices in Icom preamps AG-25 AG-35 > For the AG-35, it's a 2SK121Y. Not sure about the AG-25. > > As others have mentioned, because of the proximity of the relay, one of the > easiest ways to replace it is to cut the leads on the old device, then bend > & trim the leads on the new device to "straddle" the old leads & solder > away. Way easier than removing the relay... > > George, KA3HSW > > > ----- Original Message ----- > From: "Mark L. Hammond" <[email protected]> > To: <[email protected]> > Sent: Wednesday, March 17, 2010 5:29 PM > Subject: [amsat-bb] Devices in Icom preamps AG-25 AG-35 > > > > Hello all, > > > > We either had two bad preamps to begin with, or they became casualties > > during transport to K4T, but regardless--the Icom preamps we took appear > > to have bad GAsFET devices in them. > > > > Can anybody tell me what is the device in each unit (AG-25 and AG-35)? > > And are they something a skilled ham can reasonably replace? > > > > Specific suggestions for a parts source will be appreciated, too. > > > > 73, > > > > Mark L. Hammond [N8MH] > > _______________________________________________ > 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 _______________________________________________ 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
