> If "Joe Ham" were serious about weak signal reception, he'd mount the
> preamp at the antenna. Otherwise, 3 dB is already a lot of loss to
> tolerate for weak signal work; what's another dB?
Us northeastern Joe Ham types don't like climbing the tower during the
middle of the January contest w
At 08:36 AM 2/13/2007, you wrote:
>If "Joe Ham" were serious about weak signal reception, he'd mount the
>preamp at the antenna. Otherwise, 3 dB is already a lot of loss to
>tolerate for weak signal work; what's another dB?
<---Not just the loss but those 3 dB of feedline loss translate to an
At 2/13/2007 06:28, you wrote:
> > Your math looks sound, Jeff, except I thought 1/2" Heliax
> > wasn't quite so
> > lossy @ 450 MHz (~1.5 dB/100 ft IIRC?).
>
> > >Scenario 1: Preamp = 0.5 dB NF, antenna feeding 200' of
> > 1/2" Heliax (3
> > >dB loss @ 450 MHz @ 1:1 VSWR)
>
>1.5 dB per 100 ft ve
> Your math looks sound, Jeff, except I thought 1/2" Heliax
> wasn't quite so
> lossy @ 450 MHz (~1.5 dB/100 ft IIRC?).
> >Scenario 1: Preamp = 0.5 dB NF, antenna feeding 200' of
> 1/2" Heliax (3
> >dB loss @ 450 MHz @ 1:1 VSWR)
1.5 dB per 100 ft versus 3 dB for 200'. I think we're in agre
At 2/12/2007 03:05 PM, you wrote:
> > True, but the original question was if the noise figure of a
> > preamp was
> > degraded by the poor input match looking into the preamp
> > itself, & the
> > answer is no.
>
>Bob,
>
>Actually, my question wasn't in regard to the NF of the preamp itself,
>but
> True, but the original question was if the noise figure of a
> preamp was
> degraded by the poor input match looking into the preamp
> itself, & the
> answer is no.
Bob,
Actually, my question wasn't in regard to the NF of the preamp itself,
but rather the resulting NF (system NF) due to th
At 2/11/2007 08:27 PM, you wrote:
> >Ponder this Bob (and anyone else). Assume the preamp input is connected
> >directly to the output port of the isolator. For the sake of argument, say
> >that the preamp has a NF of 0.5 dB, and 6 dB input return loss. The power
> >transfer from isolator output t
_
From: Repeater-Builder@yahoogroups.com
[mailto:[EMAIL PROTECTED] On Behalf Of
[EMAIL PROTECTED]
Sent: Sunday, February 11, 2007 10:23 PM
To: Repeater-Builder@yahoogroups.com
Subject: RE: [Repeater-Builder] Advanced Receiver Research Preamp 144-148
At 2/11/2007 16:02, you wrote
_
From: Repeater-Builder@yahoogroups.com
[mailto:[EMAIL PROTECTED] On Behalf Of
[EMAIL PROTECTED]
Sent: Sunday, February 11, 2007 10:23 PM
To: Repeater-Builder@yahoogroups.com
Subject: RE: [Repeater-Builder] Advanced Receiver Research Preamp 144-148
At 2/11/2007 16:02, you wrote
At 2/11/2007 16:02, you wrote:
> > If you really want to isolate the preamp from the duplexer,
> > you need to put
> > an isolator ahead of it.
> >
> > Bob NO6B
>
> From a matching standpoint, yeah, but now the NF goes up due to the added
>losses of the isolator. You might come out ahead by modif
> If you really want to isolate the preamp from the duplexer,
> you need to put
> an isolator ahead of it.
>
> Bob NO6B
>From a matching standpoint, yeah, but now the NF goes up due to the added
losses of the isolator. You might come out ahead by modifying/retuning the
preamp's input network
At 12:53 PM 2/11/2007, you wrote:
Bottom line: I agree that Chip Angle GaAsFETs are the best. I even have
one installed as a key element in a $300,000 submillimeter-wave test system
at work. Like anything else that's man-made, as I found out, they are not
infallible.
At 2/9/2007 15:11, you wrote:
> > <---I swear by my last breath that I will *never* use anything other
> > than Chip's stuff - there is simply *nothing* on the planet that
> > comes close. I've been using his preamps and multicouplers for close
> > to 20 years now and have *never* been disappointed
At 2/9/2007 13:32, you wrote:
>Has anyone else looked at the input return loss on their ARR preamp? I had
>one that, when put in place, was throwing off the tuning of a two-cavity
>bandpass filter I had ahead of it. I swept it and found the return loss to
>only be about 5 dB. I put an Angle Lin
have an IFR 1200S that's running a tad bit warm. I think I'll drill
some holes into that to, and see if the performance improves.
Don, KD9PT
- Original Message -
From: "Nate Duehr" <[EMAIL PROTECTED]>
To:
Sent: Friday, February 09, 2007 4:59 PM
Subject: Re: [Repe
have an IFR 1200S that's running a tad bit warm. I think I'll drill
some holes into that to, and see if the performance improves.
Don, KD9PT
- Original Message -
From: "Nate Duehr" <[EMAIL PROTECTED]>
To:
Sent: Friday, February 09, 2007 4:59 PM
Subject: Re: [Repe
I guess I got an education here tonight with all the users responding . . .
.
Don, KD9PT
- Original Message -
From: "Jeff DePolo" <[EMAIL PROTECTED]>
To:
Sent: Friday, February 09, 2007 4:54 PM
Subject: RE: [Repeater-Builder] Advanced Receiver Research Preamp 144-14
Subject: RE: [Repeater-Builder] Advanced Receiver Research Preamp 144-148
>> For those who are inquiring minds and not up to all of the
>> terminology, what
>> is a "golden screwdriver"?
>
> Using the "golden screwdriver" means somebody went and diddl
At 03:11 PM 2/9/2007, you wrote:
>I agree 100%. I've NEVER had any of Chip's preamps fail. Ever. Out of
>probably 50 or more in service, amateur and otherwise. They just work.
<---Well, I managed to kill one or two when I was first setting up my
EME station. Chip's repairs were fast and reasona
-
From: "Jeff DePolo" <[EMAIL PROTECTED]>
To:
Sent: Friday, February 09, 2007 3:32 PM
Subject: RE: [Repeater-Builder] Advanced Receiver Research Preamp 144-148
>
> Has anyone else looked at the input return loss on their ARR preamp? I
> had
> one that, when put in place
At 03:11 PM 2/9/2007, you wrote:
>About a month ago I decomissioned a 220 ACSSB LTR system, including a
>Sinclair combiner and multicoupler. I was suprised (pleasantly) to find
>that Sinclair used one of Chip's high-level preamps in the multicoupler!
> or
> large amounts of wiring bundled with jap-wrap (cheap vinyl electrical
> tape)
Hey, thanks, I learned a new term today! That one will come in handy!
--- Jeff
> <---I swear by my last breath that I will *never* use anything other
> than Chip's stuff - there is simply *nothing* on the planet that
> comes close. I've been using his preamps and multicouplers for close
> to 20 years now and have *never* been disappointed (nor have I ever
> been disappoin
Hey Jeff,
I have a very dear friend who cannot keep from 'improving' on alignment.
This started with the old railroad T43GGV up to the Regency RH250B, and an
Atlas 210. I gave this fellow the RH250B, tuned and programmed for the
local 2M FM repeaters and put a stick on seal on the case - Bill,
On 2/9/07, Don Kupferschmidt <[EMAIL PROTECTED]> wrote:
> For those who are inquiring minds and not up to all of the terminology, what
> is a "golden screwdriver"?
The golden screwdriver is either:
1. The device used by a novice/idiot to "screw something up".
2. Sometimes also used as a referenc
Don Kupferschmidt wrote:
>
>
> Hi Jeff,
>
> "Then, last week, a friend brought over his 440 duplexer (Wacom 678) and
> asked me to tune it on the network analyzer as it had been victimized by
> the
> golden screwdriver."
>
> For those who are inquiring minds and not up to all of the terminol
Don if you were ever in CB ,We had a Golden screwdriver But after
upgrading to Ham Radio We got platinum screw Drivers Ha Ha
It is basically a Term that was Used when a Person would Peak and Tweak the
Radios, An example trying to get 2 more Watts that would not make a
difference anyway, just
At 01:32 PM 2/9/2007, you wrote:
>Has anyone else looked at the input return loss on their ARR preamp? I had
>one that, when put in place, was throwing off the tuning of a two-cavity
>bandpass filter I had ahead of it. I swept it and found the return loss to
>only be about 5 dB. I put an Angle Li
> For those who are inquiring minds and not up to all of the
> terminology, what
> is a "golden screwdriver"?
Using the "golden screwdriver" means somebody went and diddled with
something that they shouldn't have diddled with, and probably did so without
using any test equipment.
I don't know
ewdriver"?
Don, KD9PT
- Original Message -
From: "Jeff DePolo" <[EMAIL PROTECTED]>
To:
Sent: Friday, February 09, 2007 3:32 PM
Subject: RE: [Repeater-Builder] Advanced Receiver Research Preamp 144-148
>
> Has anyone else looked at the input return loss on their
Gentlemen,
It has my experince that pretty much all* the manufacturers of equipment in
our field are very helpful. All it takes usually is a phone call or email and
you can get all kinds of info.
*now, a certain 'bat wing' company may be the exception if you don't have an
account
Has anyone else looked at the input return loss on their ARR preamp? I had
one that, when put in place, was throwing off the tuning of a two-cavity
bandpass filter I had ahead of it. I swept it and found the return loss to
only be about 5 dB. I put an Angle Linear preamp in its place and all wa
Seems like ARR sells them for around $15 each. sb
Wayne, They will Know http://www.advancedreceiver.com/index1.html I
sent one in it was Fixed Very Fast, Tuned to My Repeater for less then
half price of a new one .
Good Luck
Don KA9QJG
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