Sounds like you have the hard part already licked! Let us know what the
sensitivity is after the mods.
--- Jeff WN3A
> -----Original Message-----
> From: [email protected]
> [mailto:[email protected]] On Behalf Of Chris Curtis
> Sent: Monday, June 29, 2009 3:27 PM
> To: [email protected]
> Subject: RE: [Repeater-Builder] Exec II receiver fiddling
> WAS:MastrII Receiver Failure
>
>
>
> Yes, I have the coils out already.
> Was just "touching base" about the entire casting.
>
> I have a couple "pens" in the multi-hundred watt range.
> Some thick solder wick, and there they were.
> =]
>
> Chris
> Kb0wlf
>
> > -----Original Message-----
> > From: [email protected]
> <mailto:Repeater-Builder%40yahoogroups.com> [mailto:Repeater-
> > [email protected] <mailto:Builder%40yahoogroups.com>
> ] On Behalf Of de W5DK
> > Sent: Monday, June 29, 2009 2:11 PM
> > To: [email protected]
> <mailto:Repeater-Builder%40yahoogroups.com>
> > Subject: RE: [Repeater-Builder] Exec II receiver fiddling
> WAS:MastrII
> > Receiver Failure
> >
> > Yes, be careful not to strip any screws when you try to get the
> > back/bottom
> > open. He was saying it takes allot of heat to get the helical coil
> > unsoldered from the side of the casting (once you have it
> open you will
> > see). I have used a propane torch setting stationary on a
> bench while
> > holding the casting in one hand and a pair of needle nose
> in the other,
> > I
> > hold that joint in the heat till it flows or till I had to put on a
> > glove or
> > drop the casting hihi.
> >
> > Don Kirchner W5DK
> >
> > -----Original Message-----
> > From: [email protected]
> <mailto:Repeater-Builder%40yahoogroups.com>
> > [mailto:[email protected]
> <mailto:Repeater-Builder%40yahoogroups.com> ] On Behalf Of
> Chris Curtis
> > Sent: Monday, June 29, 2009 1:42 PM
> > To: [email protected]
> <mailto:Repeater-Builder%40yahoogroups.com>
> > Subject: RE: [Repeater-Builder] Exec II receiver fiddling
> WAS:MastrII
> > Receiver Failure
> >
> > On my exec II receiver, the "casting" is just screwed together.
> > Correct?
> >
> > Chris
> > Kb0wlf
> >
> > > -----Original Message-----
> > > From: [email protected]
> <mailto:Repeater-Builder%40yahoogroups.com> [mailto:Repeater-
> > > [email protected]
> <mailto:Builder%40yahoogroups.com> ] On Behalf Of Jeff DePolo
> > > Sent: Friday, June 26, 2009 9:00 PM
> > > To: [email protected]
> <mailto:Repeater-Builder%40yahoogroups.com>
> > > Subject: RE: [Repeater-Builder] MastrII Receiver Failure
> > >
> > >
> > > Chuck's got you going down the right path. At 51 MHz, you probably
> > > only
> > > have to take one turn off of each of the first two coils.
> At 52 MHz
> > or
> > > higher, you might have to take off two. You need a lot of heat to
> > get
> > > the
> > > casting open (hint: a soldering gun, even a 300 watt Weller, ain't
> > > gonna cut
> > > it). Removing the coils/caps once you have the casting apart is
> > pretty
> > > straightfoward, as is removing one turn from each. It's
> not that bad
> > > of a
> > > job once you've done one or two, but the first one may
> cause you some
> > > grief.
> > > You should find that after the mods the receiver is plenty hot and
> > > should
> > > easily beat spec by a few dB. The LO/multiplier stages
> don't require
> > > any
> > > mods.
> > >
> > > If you want to cut corners, you might first see what your
> effective
> > > sensitivity is at your repeater site on 6m. You may find that the
> > > noise
> > > floor is elevated substantially, and that getting the "bench"
> > > sensitivity
> > > down from 1 uV to 0.3 uV isn't going to make a damned bit of
> > difference
> > > in
> > > the real world.
> > >
> > > --- Jeff
> > >
> > >
> > > > -----Original Message-----
> > > > From: [email protected]
> <mailto:Repeater-Builder%40yahoogroups.com>
> > > > [mailto:[email protected]
> <mailto:Repeater-Builder%40yahoogroups.com> ] On Behalf Of
> Chris Curtis
> > > > Sent: Friday, June 26, 2009 4:16 PM
> > > > To: [email protected]
> <mailto:Repeater-Builder%40yahoogroups.com>
> > > > Subject: RE: [Repeater-Builder] MastrII Receiver Failure
> > > >
> > > >
> > > >
> > > > You are correct sir, no mesh.
> > > > Isn't that that pits.
> > > >
> > > > So I take it I'll be removing some windings from the
> underside of
> > > said
> > > > trimmer caps?
> > > > Or is there an easier route to sensitivity?
> > > > =]
> > > >
> > > > Chris,
> > > > Kb0wlf
> > > >
> > > > > -----Original Message-----
> > > > > From: [email protected]
> <mailto:Repeater-Builder%40yahoogroups.com>
> > > > <mailto:Repeater-Builder%40yahoogroups.com> [mailto:Repeater-
> > > > > [email protected]
> <mailto:Builder%40yahoogroups.com> <mailto:Builder%40yahoogroups.com>
> > > > ] On Behalf Of Chuck Kelsey
> > > > > Sent: Friday, June 26, 2009 12:09 PM
> > > > > To: [email protected]
> <mailto:Repeater-Builder%40yahoogroups.com>
> > > > <mailto:Repeater-Builder%40yahoogroups.com>
> > > > > Subject: Re: [Repeater-Builder] MastrII Receiver Failure
> > > > >
> > > > > Do the two front end trimmer caps still have some "mesh"
> > > > left, or are
> > > > > they
> > > > > at minimum capacitance? That may be your problem.
> > > > >
> > > > > Chuck
> > > > > WB2EDV
> > > > >
> > > > >
> > > > >
> > > > > ----- Original Message -----
> > > > > From: "Chris Curtis" <[email protected]
> <mailto:demoman%40rollanet.org>
> > > > <mailto:demoman%40rollanet.org> >
> > > > > To: <[email protected]
> <mailto:Repeater-Builder%40yahoogroups.com>
> > > > <mailto:Repeater-Builder%40yahoogroups.com> >
> > > > > Sent: Friday, June 26, 2009 10:45 AM
> > > > > Subject: RE: [Repeater-Builder] MastrII Receiver Failure
> > > > >
> > > > >
> > > > > I have a mastr EXEC II receiver (33 split) that I can't get
> > > > sensitivity
> > > > > to
> > > > > increase.
> > > > >
> > > > > I replaced the fet as outlined below on the mastr II query.
> > > > > No joy though.
> > > > >
> > > > > I'm using an am/fm-1200s to tune the receiver.
> > > > >
> > > > > .5~1uv is where the receiver is coming to life.
> > > > >
> > > > > I have a couple vhf and uhf exec II receivers that tuned up
> > > > nicely in
> > > > > the
> > > > > .19~.2uv range so I "think" I'm doing/reading it correctly.
> > > > >
> > > > > Original freq was in the 46~49mHz range.
> > > > > Current crystal (icom sent to and received from Bomar) on
> > 51.75mHz.
> > > > >
> > > > > Any tips/hints/tricks to get a little more sensitivity?
> > > > >
> > > > > Thanks for the bandwidth!
> > > > >
> > > > > Chris
> > > > > Kb0wlf
> > > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > > > No virus found in this incoming message.
> > > > Checked by AVG - www.avg.com
> > > > Version: 8.5.339 / Virus Database: 270.12.85/2193 - Release
> > > > Date: 06/26/09 05:53:00
> > > >
> > > >
> > > >
> > >
> > >
> > >
> > > ------------------------------------
> > >
> > >
> > >
> > > Yahoo! Groups Links
> > >
> > >
> > >
> > > No virus found in this incoming message.
> > > Checked by AVG - www.avg.com
> > > Version: 8.5.375 / Virus Database: 270.12.83/2191 - Release Date:
> > > 06/26/09 05:53:00
> >
> >
> >
> > ------------------------------------
> >
> >
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
> >
> >
> >
> > ------------------------------------
> >
> >
> >
> > Yahoo! Groups Links
> >
> >
> >
> > No virus found in this incoming message.
> > Checked by AVG - www.avg.com
> > Version: 8.5.375 / Virus Database: 270.12.83/2191 - Release Date:
> > 06/29/09 05:54:00
>
>
>
>
>
> No virus found in this incoming message.
> Checked by AVG - www.avg.com
> Version: 8.5.375 / Virus Database: 270.12.85/2193 - Release
> Date: 06/29/09 05:54:00
>
>
>
