"Truck" fade! Or "backhoe" fade.
Allen Porter
Network Systems Engineering
Office: 770.369.9663
Cell: 678.984.3577
One Convergent Center
190 Bluegrass Valley Pkwy
Alpharetta, GA 30005
770.369.9000
www.convergent.com
-----Original Message-----
From: Steve Runck [mailto:steverunck@kfnw.org]
Sent: Monday, July 17, 2006 9:32 AM
To: 'CRTech'
Subject: RE: [CRTech] satellite ebno woes
Either that or somebody backed into the dish with their pickup! ;)
Steve Runck
Staff Engineer
KFNW AM-FM, Fargo, ND
701-282-5910, Ext. 235
steverunck@kfnw.org
Audio Streams at <http://www.kfnw.org>
> -----Original Message-----
> From: Porter, Allen [mailto:PorterA@convergent.com]
> Sent: Monday, July 17, 2006 7:40 AM
> To: CRTech
> Subject: RE: [CRTech] satellite ebno woes
>
>
> I can imagine a situation where the pol was never correct yet
> no carrier of sufficient strength and/or bandwidth was
> present on the other side so you had no troubles. A new
> carrier is put up on the opposite pol that now is bleeding
> over on you. Just idle speculation but I have seen this
> exact situation many times before.
>
>
>
> Allen Porter
> Network Systems Engineering
> Office: 770.369.9663
> Cell: 678.984.3577
>
>
>
> One Convergent Center
> 190 Bluegrass Valley Pkwy
> Alpharetta, GA 30005
> 770.369.9000
> www.convergent.com
>
>
>
>
> -----Original Message-----
> From: BILL TIDWELL [mailto:bill@waft.org]
> Sent: Sunday, July 16, 2006 12:08 AM
> To: CRTech
> Subject: Re: [CRTech] satellite ebno woes
>
> By adjusting the polarization I was able to go from 5.1 to 9.8 on the
> EBNo's. I just can't imagine why it would start acting up after this
> many years of running fine.
>
> Thanks for everyone's help.
>
> Bill Tidwell
>
>
>
>
>
>
> Jerry Mathis wrote:
> > On 7/13/06, Steve Runck <steverunck@kfnw.org> wrote:
> >>
> >> So things were humming along fine, and then all of a
> sudden you started
> >> losing signal? If so, I wouldn't throw the TI angle out
> too quickly
> >> but,
> >> of
> >> course, a spectrum analyzer would remove a lot of the
> guesswork. I will
> >> say
> >> that in this day of multiple potential sources of interference, I
> >> consider
> >> a
> >> TI filter to be standard equipment on my satellite dishes.
> >>
> >> Steve Runck
> >> Staff Engineer
> >> KFNW AM-FM, Fargo, ND
> >> 701-282-5910, Ext. 235
> >> steverunck@kfnw.org
> >> Audio Streams at <http://www.kfnw.org>
> >>
> >>
> >>
> >> > -----Original Message-----
> >> > From: BILL TIDWELL [mailto:bill@waft.org]
> >> > Sent: Wednesday, July 12, 2006 11:01 PM
> >> > To: CRTech
> >> > Subject: [CRTech] satellite ebno woes
> >> >
> >> >
> >> > I'm currently pulling my hair out over a satellite problem.
> >> > I have an
> >> > ABR202 receiver on Galaxy 4 (I think) and the EBNo is down to
> >> > 6 and the
> >> > sync light is flashing and getting dropouts about 4/minute.
> >> > I checked
> >> > alignment, replaced the receiver, changed the LNB, and
> made sure the
> >> > cable was OK. No bugs or water and it has a pretty
> clear shot with a
> >> > 3.7 meter dish. The last thing I'm going to try is an
> >> > attenuator, but I
> >> > kinda doubt it will work. Symptoms haven't changed with
> any of the
> >> > above. The new LNB is a 20 degree, 60 db gain, 5 khz stable
> >> > osc. I set
> >> > the M0 setting down to 2.0 so the unit is more tolerant of
> >> > low EbNo's
> >> > before dropout, but I need to find the real problem. Someone
> >> > I talked
> >> > to didn't think much of my TI hypothesis. Is it spectrum
> >> > analyzer time?
> >> >
> >> > Bill Tidwell
> >> > WAFT
> >> >
> >> > playing engineer for WAYR in Brunswick Ga. at this time.
> >> >
> >> >
> ---------------------------------------------------------------------
> >> > For CRTech resources visit http://CRTech.org/
> >> > To unsubscribe, e-mail: crtech-unsubscribe@crtech.org
> >> > List problems? E-mail: TechStaff@CRTech.org
> >> >
> >> >
> >>
> >>
> >>
> ---------------------------------------------------------------------
> >> For CRTech resources visit http://CRTech.org/
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> >> List problems? E-mail: TechStaff@CRTech.org
> >>
> >>
> >
> > Two things I have found will make a radical difference in
> your Eb Nos:
> >
> > 1. Are you using an old Chapparel motorized feedhorn? Dump
> that sucker
> > and
> > get a single port single polarity (assuming you're not
> using the dish for
> > multiple feeds) feedhorn and put that on the dish. You
> might have to get
> > creative with the mechanical mounting, and you might need
> the adapter
> > plate
> > they sell separately to mount the feedhorn.
> >
> > 2. When you install the new feedhorn (and if you don't, then check
> > this with
> > the existing feedhorn), check the focal point adjustment. This is a
> > commonly
> > overlooked adjustment. I don't have the formula in front of me to
> > calculate
> > it, but I or someone can post it if you need it. If you
> have the dish
> > maker's specs, they should list it. When you have the distance,
> > measure from
> > the bottom of the dish (the bottom of the "bowl", that is)
> to about 1/4"
> > INSIDE the feedhorn. Again, you may have to get creative with the
> > mechanical
> > mounting of the feedhorn to get this properly set.
> >
> > I suspect this may be your problem. With the focal point improperly
> > set, you
> > are picking up both adjacent satellite signals, and you're probably
> > getting
> > interference from an adjacent satellite.
> >
> > By following the steps above, I increased the Eb on a signal we use
> > from 10
> > to 14. YMMV.
> >
> >
> --------------------------------------------------------------
> ----------
> >
> > No virus found in this incoming message.
> > Checked by AVG Free Edition.
> > Version: 7.1.394 / Virus Database: 268.9.10/387 - Release
> Date: 7/12/2006
> >
>
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>
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