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K3 PRE function question

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Randy Lake

K3 PRE function question

This is a pretty simple question regarding the K3 PREamp (not PR6). If I do
not have the PR6 does the PRE on the front panel help with RX on 6m/2m (int
module) or does it merely increase noise?
Thanks

--
Randy Lake N1KWF
73 Gunn Rd.
Keene,NH
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Edward R Cole

Re: K3 PRE function question

Just my observations on 6m with only the internal PRE on my K3
(purchased circa 2010):

I noticed a lack of sensitivity on 6m. I had a ARR P50VDG preamp
with 22-25 dB of gain which worked better than the internal
PRE. That gave me about 12 dB more gain compared with running the
PRE. Also lower NF (typ. 0.5 dB).

I then purchased a PR6-10 and that helps considerably over using the
PRE. I have used my K3+PR6-10 for copying 6m-eme signals with a
single yagi (6-element) so that speaks well of the PR6-10. I use the
ARR preamp mounted at tower top for eme and it is a little bit better
(has more gain) on very weak eme signals using JT65. I use DIGOUT-1
to control my PR6-10 and use the pass-thru connections for the
ARR. That adds nice convenience for using the two preamps.

I have a second smaller 6m yagi which I use the PR6-10, only. BTW
this is equal to my KX3 with preamp ON (which says a lot for the KX3).

My opinion is the PR6-10 makes the K3 better on higher bands than the
internal PRE (which I leave off). If you are considering getting one
its a good (if not essential) upgrade for the original K3 on 6m and
10m. Yes, you will see a small rise in the noise reading on the
s-meter (due to more gain), but sensitivity is improved more than
that (due to lower NF). I see about S3-4 noise floor on 6m with the
PR6-10 and S5 with the ARR. PRE runs maybe S1 (a guess as I haven't
used it for some time).

73, Ed - KL7UW
--------------------------------------------

Date: Thu, 30 Nov 2017 07:25:09 -0500
From: Randy Lake <[hidden email]>
To: Elecraft List <[hidden email]>
Subject: [Elecraft] K3 PRE function question
Message-ID:
<CACnmA1PE1UX0MRuU=[hidden email]>
Content-Type: text/plain; charset="UTF-8"

This is a pretty simple question regarding the K3 PREamp (not PR6). If I do
not have the PR6 does the PRE on the front panel help with RX on 6m/2m (int
module) or does it merely increase noise?
Thanks

73, Ed - KL7UW
http://www.kl7uw.com
Dubus-NA Business mail:
[hidden email]

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Grant Youngman-2

Re: K3 PRE function question

Do you have the KXV3B with the new/improved preamp installed? I not, you should consider it.

Grant NQ5T
K3 #2091, KX3 #8342

> On Dec 1, 2017, at 10:53 AM, Edward R Cole <[hidden email]> wrote:
>
> Just my observations on 6m with only the internal PRE on my K3 (purchased circa 2010):
>
> I noticed a lack of sensitivity on 6m. I had a ARR P50VDG preamp with 22-25 dB of gain which worked better than the internal PRE. That gave me about 12 dB more gain compared with running the PRE. Also lower NF (typ. 0.5 dB).
>

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w8fn

Re: K3 PRE function question

In reply to this post by Edward R Cole

I sure envy those of you who live in a quiet enough environment to take
advantage of that much gain. Here in the city the noise level is so high
even on 6 meters that even the additional gain provided by the built-in
preamp on the KXV3B module usually only brings the noise level up; weak
signals are still buried in all the ambient crap. I previously used a
PR6 on my K3 and don't really see much difference between it and the
preamp in the Transverter module. I'm looking forward more and more to
retirement and a move out of the city.

73...
Randy, W8FN

On 12/1/2017 9:53 AM, Edward R Cole wrote:

> Just my observations on 6m with only the internal PRE on my K3
> (purchased circa 2010):
>
> I noticed a lack of sensitivity on 6m. I had a ARR P50VDG preamp with
> 22-25 dB of gain which worked better than the internal PRE. That gave
> me about 12 dB more gain compared with running the PRE. Also lower NF
> (typ. 0.5 dB).
>
> I then purchased a PR6-10 and that helps considerably over using the
> PRE. I have used my K3+PR6-10 for copying 6m-eme signals with a
> single yagi (6-element) so that speaks well of the PR6-10. I use the
> ARR preamp mounted at tower top for eme and it is a little bit better
> (has more gain) on very weak eme signals using JT65. I use DIGOUT-1
> to control my PR6-10 and use the pass-thru connections for the ARR.
> That adds nice convenience for using the two preamps.
>
> I have a second smaller 6m yagi which I use the PR6-10, only. BTW
> this is equal to my KX3 with preamp ON (which says a lot for the KX3).
>
> My opinion is the PR6-10 makes the K3 better on higher bands than the
> internal PRE (which I leave off). If you are considering getting one
> its a good (if not essential) upgrade for the original K3 on 6m and
> 10m. Yes, you will see a small rise in the noise reading on the
> s-meter (due to more gain), but sensitivity is improved more than that
> (due to lower NF). I see about S3-4 noise floor on 6m with the PR6-10
> and S5 with the ARR. PRE runs maybe S1 (a guess as I haven't used it
> for some time).
>
> 73, Ed - KL7UW

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wayne burdick

Re: K3 PRE function question

Administrator

This is why about half of our product line is intended for use outdoors, hopefully far from most noise sources. I’m always amazed to see noise drop from S6 to S0 on 20 meters, for example, when I hike up the hill at a park that’s a quarter mile from civilization.

If you do it often enough, you can cancel your gym membership :)

Wayne
N6KR

> On Dec 1, 2017, at 10:25 AM, Randy Farmer <[hidden email]> wrote:
>
> I sure envy those of you who live in a quiet enough environment to take advantage of that much gain. ....

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Edward R Cole

Re: K3 PRE function question

In reply to this post by Randy Lake

Wayne and all:

A graphic example is my experience when I first arrived in Alaska to
live in a small town of 75 people at end of 16-mile dead-end gravel
road surrounded by the Chugach NF. I rented a one-room cabin 14x16
foot with a wood stove- that's all. No electricity, no telephone, no
running water, no toilet - just an outhouse. Nearest electric power
was 3-miles away. Hooking up my battery operted TS-180S to a 80m
dipole the s-meter did not budge off zero. I could hear out to
800-1000 mile everynight on 80m. All HF bands were quiet.

Ten years later the electric utility extended lines to my property
and I had both power and phone service. Noise went up to
S3. Population of the town grew to 150 and the main road was paved.

Now I live about 100 miles west of there in a community of 4,000+ 12
miles from a small city of 7,500. 80m runs S5 on a quiet day; 6m is
also S5 noise floor.

So good luck finding that quiet place (beyond civilization)! I live
on the Kenai Peninsula of Alaska with area about the same as Ireland
and pop of 55,000. Everyone has wireless junk so "there goes the
neighborhood".

I still can hear the occasional ATV, dirt bike or snowmachine pass
by the house.

Next move is the backside of the Moon! LOL
73, Ed - KL7UW

Date: Fri, 1 Dec 2017 10:51:41 -0800
From: Wayne Burdick <[hidden email]>
To: Randy Farmer <[hidden email]>
Cc: Elecraft Reflector <[hidden email]>
Subject: Re: [Elecraft] K3 PRE function question
Message-ID: <[hidden email]>
Content-Type: text/plain; charset=utf-8

This is why about half of our product line is intended for use
outdoors, hopefully far from most noise sources. I?m always amazed to
see noise drop from S6 to S0 on 20 meters, for example, when I hike
up the hill at a park that?s a quarter mile from civilization.

If you do it often enough, you can cancel your gym membership :)

Wayne
N6KR

73, Ed - KL7UW
http://www.kl7uw.com
Dubus-NA Business mail:
[hidden email]

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Bill Frantz

Re: K3 PRE function question

In reply to this post by wayne burdick

I live on a long, thin lot is suburbia. My house, and my
neighbor's houses are at the street end of our lots leaving lots
of area behind. I have found that the RF noise in the back part
of our lot is much lower than in the front part. That's where I
try to put my antennas.

73 Bill AE6JV

On 12/1/17 at 10:51 AM, [hidden email] (Wayne Burdick) wrote:

>This is why about half of our product line is intended for use
>outdoors, hopefully far from most noise sources. I’m always
>amazed to see noise drop from S6 to S0 on 20 meters, for
>example, when I hike up the hill at a park that’s a quarter
>mile from civilization.

-------------------------------------------------------------------------
Bill Frantz | When it comes to the world | Periwinkle
(408)356-8506 | around us, is there any choice | 16345
Englewood Ave
www.pwpconsult.com | but to explore? - Lisa Randall | Los Gatos,
CA 95032

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Doug Person-4

Re: K3 PRE function question

In reply to this post by Edward R Cole

That seems odd. I live in a community of about 2000 spread over an area
of 450 square miles. There is power and phone service to every house.
Internet is either satellite or over the cellular network. My noise
level on 20 meters is less than S1 and usually doesn't even move the
meter. 80 and 40 are typical of atmospheric conditions. Even on my
full-size 40 meter vertical the noise level is typically S1 to S2.

You must just have some really bad luck. I think I live in a typical
rural community where the only real noise generator is a cranky electric
fence.

Doug -- K0DXV

On 12/1/17 6:49 PM, Edward R Cole wrote:

> Wayne and all:
>
> A graphic example is my experience when I first arrived in Alaska to
> live in a small town of 75 people at end of 16-mile dead-end gravel
> road surrounded by the Chugach NF. I rented a one-room cabin 14x16
> foot with a wood stove- that's all. No electricity, no telephone, no
> running water, no toilet - just an outhouse. Nearest electric power
> was 3-miles away. Hooking up my battery operted TS-180S to a 80m
> dipole the s-meter did not budge off zero. I could hear out to
> 800-1000 mile everynight on 80m. All HF bands were quiet.
>
> Ten years later the electric utility extended lines to my property and
> I had both power and phone service. Noise went up to S3. Population
> of the town grew to 150 and the main road was paved.
>
> Now I live about 100 miles west of there in a community of 4,000+ 12
> miles from a small city of 7,500. 80m runs S5 on a quiet day; 6m is
> also S5 noise floor.
>
> So good luck finding that quiet place (beyond civilization)! I live
> on the Kenai Peninsula of Alaska with area about the same as Ireland
> and pop of 55,000. Everyone has wireless junk so "there goes the
> neighborhood".
>
> I still can hear the occasional ATV, dirt bike or snowmachine pass by
> the house.
>
> Next move is the backside of the Moon! LOL
> 73, Ed - KL7UW
>
> Date: Fri, 1 Dec 2017 10:51:41 -0800
> From: Wayne Burdick <[hidden email]>
> To: Randy Farmer <[hidden email]>
> Cc: Elecraft Reflector <[hidden email]>
> Subject: Re: [Elecraft] K3 PRE function question
> Message-ID: <[hidden email]>
> Content-Type: text/plain; charset=utf-8
>
> This is why about half of our product line is intended for use
> outdoors, hopefully far from most noise sources. I?m always amazed to
> see noise drop from S6 to S0 on 20 meters, for example, when I hike up
> the hill at a park that?s a quarter mile from civilization.
>
> If you do it often enough, you can cancel your gym membership :)
>
> Wayne
> N6KR
>
>
> 73, Ed - KL7UW
> http://www.kl7uw.com
> Dubus-NA Business mail:
> [hidden email]
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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> Post: mailto:[hidden email]
>
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> Message delivered to [hidden email]

Bob McGraw - K4TAX

Re: K3 PRE function question

Got one of those "cranky electric fence" across the highway. The Noise
Blanker does a wonderful job of making it go away and not punch holes in
the signal at the same time. Thanks Elecraft!

73

Bob, K4TAX

On 12/2/2017 9:05 AM, Doug Person wrote:

> That seems odd. I live in a community of about 2000 spread over an
> area of 450 square miles. There is power and phone service to every
> house. Internet is either satellite or over the cellular network. My
> noise level on 20 meters is less than S1 and usually doesn't even move
> the meter. 80 and 40 are typical of atmospheric conditions. Even on my
> full-size 40 meter vertical the noise level is typically S1 to S2.
>
> You must just have some really bad luck. I think I live in a typical
> rural community where the only real noise generator is a cranky
> electric fence.
>
> Doug -- K0DXV
>
> On 12/1/17 6:49 PM, Edward R Cole wrote:
>> Wayne and all:
>>
>> A graphic example is my experience when I first arrived in Alaska to
>> live in a small town of 75 people at end of 16-mile dead-end gravel
>> road surrounded by the Chugach NF. I rented a one-room cabin 14x16
>> foot with a wood stove- that's all. No electricity, no telephone, no
>> running water, no toilet - just an outhouse. Nearest electric power
>> was 3-miles away. Hooking up my battery operted TS-180S to a 80m
>> dipole the s-meter did not budge off zero. I could hear out to
>> 800-1000 mile everynight on 80m. All HF bands were quiet.
>>
>> Ten years later the electric utility extended lines to my property
>> and I had both power and phone service. Noise went up to S3.
>> Population of the town grew to 150 and the main road was paved.
>>
>> Now I live about 100 miles west of there in a community of 4,000+ 12
>> miles from a small city of 7,500. 80m runs S5 on a quiet day; 6m is
>> also S5 noise floor.
>>
>> So good luck finding that quiet place (beyond civilization)! I live
>> on the Kenai Peninsula of Alaska with area about the same as Ireland
>> and pop of 55,000. Everyone has wireless junk so "there goes the
>> neighborhood".
>>
>> I still can hear the occasional ATV, dirt bike or snowmachine pass
>> by the house.
>>
>> Next move is the backside of the Moon! LOL
>> 73, Ed - KL7UW
>>
>> Date: Fri, 1 Dec 2017 10:51:41 -0800
>> From: Wayne Burdick <[hidden email]>
>> To: Randy Farmer <[hidden email]>
>> Cc: Elecraft Reflector <[hidden email]>
>> Subject: Re: [Elecraft] K3 PRE function question
>> Message-ID: <[hidden email]>
>> Content-Type: text/plain; charset=utf-8
>>
>> This is why about half of our product line is intended for use
>> outdoors, hopefully far from most noise sources. I?m always amazed to
>> see noise drop from S6 to S0 on 20 meters, for example, when I hike
>> up the hill at a park that?s a quarter mile from civilization.
>>
>> If you do it often enough, you can cancel your gym membership :)
>>
>> Wayne
>> N6KR
>>
>>
>> 73, Ed - KL7UW
>> http://www.kl7uw.com
>> Dubus-NA Business mail:
>> [hidden email]
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to [hidden email]
>
> ______________________________________________________________
> Elecraft mailing list
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> Post: mailto:[hidden email]
>
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> Message delivered to [hidden email]
>

Edward R Cole

Re: K3 PRE function question

In reply to this post by Randy Lake

Doug,

I checked 20m about 5pm and noted S3 noise but also that I had the
PRE turned on. With preamp off 20m noise is running S2. But both
40m and 80m see S6 noise on my inverted-V hung on the tower under the
triband yagi. This high for usual on these bands for here (yes, PRE is off).

I looked up your location which is in the mountains near Steamboat in
northern CO. 2000 pop/480 sq miles = 4 people per sq-mi which is way
less density from where I live. 4,200 in a 16x 10 mile strip along
the western shore of the Kenai Peninsula. Density = 4200/160 = 26
people per sq-mi. But that is not accurate for my nearby density
around a lake with average property size of 2-3 acres and 2.5 persons
per property. Probably 200-300 within a mile. All have wireless
devices and consumer electronics galore. Many are line of sight
across the lake. I do have buired utilities in the near 1/4 mile but
overhead wired beyond that. Internet is phone line DSL and TV by satellite.

Also we have a refinery, LNG plant, and local gas-trubine generation
station 2-miles to the west. 12 miles south is a city with 7500
people in typical city density and many stores and businesses (lots
of digital cash registers). Another city of 7500 lies another 11
miles south to the first so in 30-mile radius we have a pop of about 30,000.

I would guess that is not at all comparable to where you live.

Alaska has ground conductivity problems with frozen soil which really
affects electrical noise. But if you get out in roadless bush its as
quiet at you make your home electronics (and generator).

73, Ed - KL7UW

Date: Sat, 2 Dec 2017 08:05:16 -0700
From: Doug Person <[hidden email]>
To: [hidden email]
Subject: Re: [Elecraft] K3 PRE function question
Message-ID: <[hidden email]>
Content-Type: text/plain; charset=windows-1252; format=flowed

That seems odd. I live in a community of about 2000 spread over an area
of 450 square miles. There is power and phone service to every house.
Internet is either satellite or over the cellular network. My noise
level on 20 meters is less than S1 and usually doesn't even move the
meter. 80 and 40 are typical of atmospheric conditions. Even on my
full-size 40 meter vertical the noise level is typically S1 to S2.

You must just have some really bad luck. I think I live in a typical
rural community where the only real noise generator is a cranky electric
fence.

Doug -- K0DXV

73, Ed - KL7UW
http://www.kl7uw.com
Dubus-NA Business mail:
[hidden email]

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M0XDF

Re: K3 PRE function question

My God - if we had a lake, it would be ~ 1/8 acre per property, if you were lucky - 3-5 people per property.

I live in a medium sized town 30 miles from the centre of London, population ~ 250,000 in < 70 sq-mi :-(

73 de David, M0XDF (K3 #174, P3 #108)
--
I really hate this damn machine, I wish that they would sell it.
It never does just what I want, but only what I tell it!

> On 3 Dec 2017, at 06:53, Edward R Cole <[hidden email]> wrote:
>
> Doug,
>
> I checked 20m about 5pm and noted S3 noise but also that I had the PRE turned on. With preamp off 20m noise is running S2. But both 40m and 80m see S6 noise on my inverted-V hung on the tower under the triband yagi. This high for usual on these bands for here (yes, PRE is off).
>
> I looked up your location which is in the mountains near Steamboat in northern CO. 2000 pop/480 sq miles = 4 people per sq-mi which is way less density from where I live. 4,200 in a 16x 10 mile strip along the western shore of the Kenai Peninsula. Density = 4200/160 = 26 people per sq-mi. But that is not accurate for my nearby density around a lake with average property size of 2-3 acres and 2.5 persons per property. Probably 200-300 within a mile. All have wireless devices and consumer electronics galore. Many are line of sight across the lake. I do have buired utilities in the near 1/4 mile but overhead wired beyond that. Internet is phone line DSL and TV by satellite.
>
> Also we have a refinery, LNG plant, and local gas-trubine generation station 2-miles to the west. 12 miles south is a city with 7500 people in typical city density and many stores and businesses (lots of digital cash registers). Another city of 7500 lies another 11 miles south to the first so in 30-mile radius we have a pop of about 30,000.
>