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KX3 vs. K3 and other rigs?

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Byron Servies

Re: KX3 vs. K3 and other rigs?

The KX3 (K3 Extremely Portable is how I think of it) does have 3db of
additional power compared to the intended market: 5w QRP portable.

The portable QRP market is where Elecrafts' roots lie, after all, so
it should be no surprise that the KX3 is aimed at that target. Having
an optional external 100w amplifier makes it practical for field day
and other mobile operations, too, and perhaps some really constrained
home stations where even a small K3 will not fit.

On Mon, Jun 6, 2011 at 11:14 AM, Keith-K5ENS <[hidden email]> wrote:
> I know many a contest station that would and have spent $1000's for an extra
> 3db. There must to a reason.

73, Byron N6NUL
----
- Northern California Contest Club
- CU in the 2011 Cal QSO Party 1-2 Oct 2011
- www.cqp.org
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drewko

Re: KX3 vs. K3 and other rigs?

In reply to this post by Alan Bloom

There is another way of looking at it-- how many additional contacts
would potentially be available by utilizing an increase of just 3db?

I don't know the answer but there is a somewhat analogous situation in
astronomy having to do with the brightness of stars. They are also
measured on a logarithmic scale, called magnitude, each magnitude
representing twice or half the brightness level of the following or
preceding magnitude. A difference of one magnitude does not appear
very large to the eye, yet the ability to see one magnitude fainter
can yield three times as many stars. I imagine some similar effect
might pertain to radio waves.

BTW, I'm not asking for more power in the KX3; would be quite content
with 10 watts, same as my K3.

73,
Drew
AF2Z

On Mon, 06 Jun 2011 08:56:48 -0700, Alan N1AL wrote:

>On Mon, 2011-06-06 at 08:10 -0700, juergen wrote:
>
>> However from a communications effectiveness point of 20 watts is a
>> much more realistic power level, especially for SSB QSO's.
>
>The difference between 10 and 20 watts is only 3 dB, half an S-unit.
>Compared to the 20-30 dB of QSB you often find on the HF bands, you
>would hardly even notice such a small difference. I think it is quite
>rare that 3 dB would be the difference between making a contact or not.
>
>Alan N1AL
>

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Pete Smith N4ZR

What is a dB worth was: Re: KX3 vs. K3 and other rigs?

It is pretty widely accepted in contesting that an improvement in
*either* receive or transmit capability of 1 dB will yield a useful
increase in the number of QSOs over a 48-hour contest, even if it has an
indiscernible effect on 99.5 percent of your contacts.

73, Pete N4ZR

The World Contest Station Database, updated daily at www.conteststations.com
The Reverse Beacon Network at http://reversebeacon.net, blog at reversebeacon.blogspot.com,
spots at telnet.reversebeacon.net, port 7000

On 6/7/2011 8:23 AM, drewko wrote:

> There is another way of looking at it-- how many additional contacts
> would potentially be available by utilizing an increase of just 3db?
>
> I don't know the answer but there is a somewhat analogous situation in
> astronomy having to do with the brightness of stars. They are also
> measured on a logarithmic scale, called magnitude, each magnitude
> representing twice or half the brightness level of the following or
> preceding magnitude. A difference of one magnitude does not appear
> very large to the eye, yet the ability to see one magnitude fainter
> can yield three times as many stars. I imagine some similar effect
> might pertain to radio waves.
>
> BTW, I'm not asking for more power in the KX3; would be quite content
> with 10 watts, same as my K3.
>
> 73,
> Drew
> AF2Z
>
>
> On Mon, 06 Jun 2011 08:56:48 -0700, Alan N1AL wrote:
>
>> On Mon, 2011-06-06 at 08:10 -0700, juergen wrote:
>>
>>> However from a communications effectiveness point of 20 watts is a
>>> much more realistic power level, especially for SSB QSO's.
>> The difference between 10 and 20 watts is only 3 dB, half an S-unit.
>> Compared to the 20-30 dB of QSB you often find on the HF bands, you
>> would hardly even notice such a small difference. I think it is quite
>> rare that 3 dB would be the difference between making a contact or not.
>>
>> Alan N1AL
>>
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>

Rose

What is a dB worth was: Re: KX3 vs. K3 and other rigs?

There's a saying among VHF / UHF'ers in reference
to coax and connector losses that every .5db counts.

73! Ken - K0PP
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Gary Gregory

Re: KX3 vs. K3 and other rigs?

In reply to this post by drewko

The 10W output of the KX3 can be increased to 100W via the amplifier for
mobile and portable operation. To increase the output from 10 to say 30W
will greatly restrict the battery life and I don't see any real advantage.

Either the KX3 is a QRP radio or not....adding another 10-20W available on
battery power makes it less attractive to me.

In VK we seem to be able to work the world on 400W and yet there are those
in VK who want a change to 1Kw....will it allow us to work more
stations?.....maybe...maybe not. Perhaps we are just too lazy to make a few
extra calls and think it is good to be told we are 20db over S9 instead of
5/9 plus....

I have worked a lot of stations running QRP and a dipole antenna and the
last was from NY to VK using 5W, I went QRP also and we worked for 10
minutes or so. It was fun for me to work him also.

My 2 cents worth...keep the change!

73's
Gary

On 7 June 2011 22:23, drewko <[hidden email]> wrote:

> There is another way of looking at it-- how many additional contacts
> would potentially be available by utilizing an increase of just 3db?
>
> I don't know the answer but there is a somewhat analogous situation in
> astronomy having to do with the brightness of stars. They are also
> measured on a logarithmic scale, called magnitude, each magnitude
> representing twice or half the brightness level of the following or
> preceding magnitude. A difference of one magnitude does not appear
> very large to the eye, yet the ability to see one magnitude fainter
> can yield three times as many stars. I imagine some similar effect
> might pertain to radio waves.
>
> BTW, I'm not asking for more power in the KX3; would be quite content
> with 10 watts, same as my K3.
>
> 73,
> Drew
> AF2Z
>
>
> On Mon, 06 Jun 2011 08:56:48 -0700, Alan N1AL wrote:
>
> >On Mon, 2011-06-06 at 08:10 -0700, juergen wrote:
> >
> >> However from a communications effectiveness point of 20 watts is a
> >> much more realistic power level, especially for SSB QSO's.
> >
> >The difference between 10 and 20 watts is only 3 dB, half an S-unit.
> >Compared to the 20-30 dB of QSB you often find on the HF bands, you
> >would hardly even notice such a small difference. I think it is quite
> >rare that 3 dB would be the difference between making a contact or not.
> >
> >Alan N1AL
> >
>
> ______________________________________________________________
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--

VK4FD - Motorhome Mobile
Elecraft Equipment
K3 #679, KPA-500 #018
Living the dream!!!
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Jim Low man

Re: KX3 vs. K3 and other rigs?

I can understand the advantage of even 1 db to a serious contester over
the period
of a lengthy contest but for my needs, and keeping in mind maximizing
battery power,
the 10w of the KX3, and even 5w, is fine. I have other rigs that are
capable of 100w
in the shack, but now that I'm retired I plan to do a lot of portable
work, especially
since summer is on the way in the northern hemisphere. Fortunately,
here in soCal
it's nice enough to do portable operations most of the year, without the
need for
much more than a jacket in winter.

I guess that getting older tends to mellow one out. In the past I was
an extremely
serious contester, especially for Field Day, but now I'll be content to
improve on
last year's score in a given contest. Sure, in a stocked pond you're
pretty much
guaranteed to catch fish, but where's the fun in that?

Being DX in VK-land gives you a bit of an advantage. I'd say that 400w
is more
than enough power, but I'm sure that there are those of us here in the
US who
would use more power than 1500w it it were allowed.

72/73 de Jim - AD6CW

On 6/7/2011 8:40 AM, Gary Gregory wrote:

> The 10W output of the KX3 can be increased to 100W via the amplifier for
> mobile and portable operation. To increase the output from 10 to say 30W
> will greatly restrict the battery life and I don't see any real advantage.
>
> Either the KX3 is a QRP radio or not....adding another 10-20W available on
> battery power makes it less attractive to me.
>
> In VK we seem to be able to work the world on 400W and yet there are those
> in VK who want a change to 1Kw....will it allow us to work more
> stations?.....maybe...maybe not. Perhaps we are just too lazy to make a few
> extra calls and think it is good to be told we are 20db over S9 instead of
> 5/9 plus....
>
> I have worked a lot of stations running QRP and a dipole antenna and the
> last was from NY to VK using 5W, I went QRP also and we worked for 10
> minutes or so. It was fun for me to work him also.
>
> My 2 cents worth...keep the change!
>
> 73's
> Gary
>

AC7AC

Re: What is a dB worth was: Re: KX3 vs. K3 and other rigs?

In reply to this post by Rose

CONTENTS DELETED

The author has deleted this message.

Dave-7

Re: KX3 vs. K3 and other rigs?

In reply to this post by drewko

To try to put some meaningful numbers on the value of a few extra dB I
looked at some recent contest scores. Actually not at the scores
themselves but the number of Q's made. There is of course wide
variability in this. A lot appears to depend on whether it is
primarily a NA contest or international. But it might give some clue
about the value of additional power.

To hopefully remove some of the many variables, I looked only at the
top few stations. The assumption is that these guys have good stations
with good antennas in good locations. Have to believe that they put in
nearly equal effort, i.e. approx the same number of hours. Implicit
also is the assumption they are approx equally good operators.

In the 2010 ARRL 160m contest these power levels made this many Q's:

1st 2nd
QRP 805 718
LP 1078 1038
HP 1989 1776

In 2010, with the low sunspot numbers, this was basically a NA
contest. Not much in the way of DX activity.

Assuming other things are equal - which may or may not be the case -
it looks like 13 dB (5w to 100w) is worth about a 33% increase in Q's.
And 25 dB (5w to 1500w) will yield somewhat more than double.

In the 2010 ARRL Sweepstakes:

1st 2nd
QRP 982 835
LP 1257 1244
HP 1466 1453

This is a NA contest.

Here 13 dB was again about a 33% increase and 25 dB something less
than double. Indeed having a KW was not much help here.

But if we look at longer distance and check the 2010 ARRL
International DX contest (looking at stations in NA, not EU or other
continents):

1st 2nd
QRP 1021 912
LP 2872 2738
HP 4362 4474

Here 13 dB gives nearly 3x as many contacts. 25 dB gives about 4.5x as
many.

It looks like a few extra dB may be valuable on longer paths, but not
worth much within NA, which is about what you would expect.

This does not address the question of what 3 dB is worth. A little
hard to figure. Within NA 13 dB yields about 33%. So what would 3 dB
yield? Dunno, but my guess is not much.

How much is 3 dB worth on longer paths? Again hard to say but there is
probably some threshold, or minimum required, to work the DX. Is that
threshold 3 dB, i.e. 10w? Honestly probably not. Somewhere between 5w
and 100w, but unknown.

Maybe some enterprising souls could get together, a few run 5w, a few
run 10w, a few 25w, and a few 50w. Compare results when it is over.

73 de dave
ab9ca/4

On 6/7/11 7:23 AM, drewko wrote:

> There is another way of looking at it-- how many additional contacts
> would potentially be available by utilizing an increase of just 3db?
>
> I don't know the answer but there is a somewhat analogous situation in
> astronomy having to do with the brightness of stars. They are also
> measured on a logarithmic scale, called magnitude, each magnitude
> representing twice or half the brightness level of the following or
> preceding magnitude. A difference of one magnitude does not appear
> very large to the eye, yet the ability to see one magnitude fainter
> can yield three times as many stars. I imagine some similar effect
> might pertain to radio waves.
>
> BTW, I'm not asking for more power in the KX3; would be quite content
> with 10 watts, same as my K3.
>
> 73,
> Drew
> AF2Z
>
>
> On Mon, 06 Jun 2011 08:56:48 -0700, Alan N1AL wrote:
>
>> On Mon, 2011-06-06 at 08:10 -0700, juergen wrote:
>>
>>> However from a communications effectiveness point of 20 watts is a
>>> much more realistic power level, especially for SSB QSO's.
>>
>> The difference between 10 and 20 watts is only 3 dB, half an S-unit.
>> Compared to the 20-30 dB of QSB you often find on the HF bands, you
>> would hardly even notice such a small difference. I think it is quite
>> rare that 3 dB would be the difference between making a contact or not.
>>
>> Alan N1AL
>>
>
> ______________________________________________________________
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David Gilbert

Re: KX3 vs. K3 and other rigs?

In reply to this post by drewko

It all depends how close the desired signal is to the noise level.
Check out

http://www.ab7e.com/weak_signal/mdd.html

However, the original argument that 20 watts is better than 10 watts
seems pretty silly to me since you can carry that flag all the way up to
power levels that create their own ionosphere. We can all gain >FAR<
more ERP from wisely choosing/building a better portable antenna
compared to a backpack whip than we would from doubling the power out of
the rig.

73,
Dave AB7E

> The difference between 10 and 20 watts is only 3 dB, half an S-unit.
> >Compared to the 20-30 dB of QSB you often find on the HF bands, you
> >would hardly even notice such a small difference. I think it is quite
> >rare that 3 dB would be the difference between making a contact or not.
> >
> >Alan N1AL
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Dave KK7SS

Re: KX3 vs. K3 and other rigs?

In reply to this post by TF3KX

IMHO it's the need to shout louder than the other guys in a pile-up!
I've been DX and heard the roar!!

>> I know many a contest station that would and have spent $1000's
>> for an extra 3db. There must to a reason.
--
Dave G KK7SS
DN06ig Richland, WA

'59 Morris Minor 1000
'65 Sprite - in process
'76 Midget - shared with my #4 son.
'06 Honda Civic Hybrid
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ac0h

Re: KX3 vs. K3 and other rigs?

In reply to this post by Gary Gregory

Aye, and there's the rub of the matter.

I just spent 20 minutes surfing the web looking for the definition of
"QRP". Of the half dozen or so well known sites I visited, in the
US and abroad, the definition of QRP is 5 Watts CW and 10W SSB MAX. Not
20 if you got it, not 30 if running on an outboard PS, etc...

The simple fact is you can't support more than 10W out and keep battery
life in the realm of reality. You can't just put a bigger battery in it
and keep the form factor.

I really don't see what the problem is.
If you're using it as a trail radio weight and battery life mean
everything. If your a dedicated QRPer 10W is the limit. If you want to
use the radio mobile buy the amp. If you want to run mobile with ridiculously inefficient antennas, and QRP your a masochist
and need to be ignored. ;-)

If none of the above fits buy a K3 and be well.

On Wed, 8 Jun 2011 01:40:27 +1000
Gary Gregory <[hidden email]> wrote:

> Either the KX3 is a QRP radio or not....adding another 10-20W
> available on battery power makes it less attractive to me.

--
R. Kevin Stover
AC0H
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K7TV

What is a dB worth

In reply to this post by TF3KX

Excellent point about seeing 3 times more stars with a gain of 1 magnitude
(although 1 magnitude is 2.5 times brighter, so a little more than 3 dB).
Also an excellent point about 1 dB yielding meaningful results in contest
score even if no difference is discernible in an individual contact. I would
add that if there is an opportunity to get small improvements in several
areas, taking the attitude of looking at impact of a single improvement on a
single contact can likewise lead to missing the big picture. Few of us can
afford going for the last 0.5 dB in every part of a home station. I know I
can't, but doing so is a lot more practical for a portable station. And
getting the results of such a pursuit may be much more important for the
portable station. Here is how I look at my portable capability. While it is
part of the ham hobby, the portable HF radio is an essential piece of safety
equipment for hiking expeditions. (OK, I could get a satellite device, but I
don't like to pay the yearly fees.) When the need for an emergency call
comes, I won't be in a good location, and the time of day won't match the
conditions. My HF radio may not in fact be able to reach anyone at all, at
least not immediately. But when I make decisions about portable gear, I want
to be able to say that I did my best, meaning I went for all those
individual 1 dB improvements that I could, within weight constraints.
Together they will make a difference, and the 7 dB of going from 2 W in my
KX1 to 10 W in a KX3 looks like a no-brainer. (I understand that the KX3
will be able to achieve 10 W using the built-in batteries.) A 30 W amp with
built-in rechargeable batteries would certainly be interesting to look at
too, but may not fit in my packing weight limits.

73,

Erik K7TV

>It is pretty widely accepted in contesting that an improvement in

>*either* receive or transmit capability of 1 dB will yield a useful
increase in the number of QSOs over a 48-hour contest, >even if it has an
indiscernible effect on 99.5 percent of your contacts.

>

>73, Pete N4ZR

>

>The World Contest Station Database, updated daily at
www.conteststations.com The Reverse Beacon Network at
>http://reversebeacon.net, blog at reversebeacon.blogspot.com, spots at
telnet.reversebeacon.net, port 7000

On 6/7/2011 8:23 AM, drewko wrote:

> There is another way of looking at it-- how many additional contacts

> would potentially be available by utilizing an increase of just 3db?

>

> I don't know the answer but there is a somewhat analogous situation in

> astronomy having to do with the brightness of stars. They are also

> measured on a logarithmic scale, called magnitude, each magnitude

> representing twice or half the brightness level of the following or

> preceding magnitude. A difference of one magnitude does not appear

> very large to the eye, yet the ability to see one magnitude fainter

> can yield three times as many stars. I imagine some similar effect

> might pertain to radio waves.

>

> BTW, I'm not asking for more power in the KX3; would be quite content

> with 10 watts, same as my K3.

>

> 73,

> Drew

> AF2Z

>

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Eric Swartz - WA6HHQ

Re: What is a dB worth [END of Thread]

Administrator

In the interest of minimizing list overhead and noise, let's end this
and related threads for now. This topic, like pro/con CW requirements
etc., reoccur endlessly on most discussion groups.

73, Eric
Elecraft List moderator
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Eric Swartz - WA6HHQ

Re: KX3 vs. K3 and other rigs? [End of QRP/Power thread]

Administrator

In reply to this post by ac0h

Let's end the power/QRP discussion.

73, Eric
List moderator

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Peter Wollan-2

Re: KX3 vs. K3 and other rigs?

In reply to this post by Dave-7

I've seen this kind of calculation before, and for some events, like
Field Day, it's clear that QRP can compete on scores quite
effectively. But that's using CW, and probably also PSK31. Dave's
numbers suggest that it might also be different for North American
contacts (for those of us within North America), compared to crossing
an ocean. But for me, SSB is much less effective -- I've too often
been able to copy people easily, and have them not react to my 10
watts at all.

But to me, that means use CW for contests, and if I try SSB I
shouldn't worry about not getting through. Meanwhile, I'll work on
better antennas, and be more persistent so that when the propagation
gods smile I'll be there.

Still, I may get this 100-watt thing when it comes out, or at least
within a year or two.

Peter W0LLN

On Tue, Jun 7, 2011 at 12:20 PM, dave <[hidden email]> wrote:
>
> To try to put some meaningful numbers on the value of a few extra dB I
> looked at some recent contest scores.
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Alan Bloom

Re: KX3 vs. K3 and other rigs?

In reply to this post by Dave-7

Interesting analysis Dave. Assuming everything is logarithmic, a 33%
increase in contacts for a 13 db power increase implies 7% more contacts
for 3 dB more power:

10^[(3/13) * log(1.33)] = 1.07

And 100% more contacts for a 25 dB power increase implies 8.7% per 3 dB:

10^[(3/25) * log (2)] = 1.087

However, I think that overstates the advantage of higher power. The
higher-power stations also probably had better antennas and other
equipment as well. But it does put a useful upper bound on the number.

In a non-competitive situation I would expect the difference to be even
less.

Alan N1AL

On Tue, 2011-06-07 at 12:20 -0500, dave wrote:

> To try to put some meaningful numbers on the value of a few extra dB I
> looked at some recent contest scores. Actually not at the scores
> themselves but the number of Q's made. There is of course wide
> variability in this. A lot appears to depend on whether it is
> primarily a NA contest or international. But it might give some clue
> about the value of additional power.
>
> To hopefully remove some of the many variables, I looked only at the
> top few stations. The assumption is that these guys have good stations
> with good antennas in good locations. Have to believe that they put in
> nearly equal effort, i.e. approx the same number of hours. Implicit
> also is the assumption they are approx equally good operators.
>
> In the 2010 ARRL 160m contest these power levels made this many Q's:
>
> 1st 2nd
> QRP 805 718
> LP 1078 1038
> HP 1989 1776
>
> In 2010, with the low sunspot numbers, this was basically a NA
> contest. Not much in the way of DX activity.
>
> Assuming other things are equal - which may or may not be the case -
> it looks like 13 dB (5w to 100w) is worth about a 33% increase in Q's.
> And 25 dB (5w to 1500w) will yield somewhat more than double.
>
> In the 2010 ARRL Sweepstakes:
>
> 1st 2nd
> QRP 982 835
> LP 1257 1244
> HP 1466 1453
>
> This is a NA contest.
>
> Here 13 dB was again about a 33% increase and 25 dB something less
> than double. Indeed having a KW was not much help here.
>
> But if we look at longer distance and check the 2010 ARRL
> International DX contest (looking at stations in NA, not EU or other
> continents):
>
> 1st 2nd
> QRP 1021 912
> LP 2872 2738
> HP 4362 4474
>
> Here 13 dB gives nearly 3x as many contacts. 25 dB gives about 4.5x as
> many.
>
> It looks like a few extra dB may be valuable on longer paths, but not
> worth much within NA, which is about what you would expect.
>
> This does not address the question of what 3 dB is worth. A little
> hard to figure. Within NA 13 dB yields about 33%. So what would 3 dB
> yield? Dunno, but my guess is not much.
>
> How much is 3 dB worth on longer paths? Again hard to say but there is
> probably some threshold, or minimum required, to work the DX. Is that
> threshold 3 dB, i.e. 10w? Honestly probably not. Somewhere between 5w
> and 100w, but unknown.
>
> Maybe some enterprising souls could get together, a few run 5w, a few
> run 10w, a few 25w, and a few 50w. Compare results when it is over.
>
>
> 73 de dave
> ab9ca/4
>
>
>
>
>
> On 6/7/11 7:23 AM, drewko wrote:
> > There is another way of looking at it-- how many additional contacts
> > would potentially be available by utilizing an increase of just 3db?
> >
> > I don't know the answer but there is a somewhat analogous situation in
> > astronomy having to do with the brightness of stars. They are also
> > measured on a logarithmic scale, called magnitude, each magnitude
> > representing twice or half the brightness level of the following or
> > preceding magnitude. A difference of one magnitude does not appear
> > very large to the eye, yet the ability to see one magnitude fainter
> > can yield three times as many stars. I imagine some similar effect
> > might pertain to radio waves.
> >
> > BTW, I'm not asking for more power in the KX3; would be quite content
> > with 10 watts, same as my K3.
> >
> > 73,
> > Drew
> > AF2Z
> >
> >
> > On Mon, 06 Jun 2011 08:56:48 -0700, Alan N1AL wrote:
> >
> >> On Mon, 2011-06-06 at 08:10 -0700, juergen wrote:
> >>
> >>> However from a communications effectiveness point of 20 watts is a
> >>> much more realistic power level, especially for SSB QSO's.
> >>
> >> The difference between 10 and 20 watts is only 3 dB, half an S-unit.
> >> Compared to the 20-30 dB of QSB you often find on the HF bands, you
> >> would hardly even notice such a small difference. I think it is quite
> >> rare that 3 dB would be the difference between making a contact or not.
> >>
> >> Alan N1AL
> >>
> >
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Jan Erik Holm

Re: What is a dB worth was: Re: KX3 vs. K3 and other rigs?

In reply to this post by Rose

Well when I was in to EME on 2m I was hunting for
every .1 dB I could find.

/Jim SM2EKM
--------------
On 2011-06-07 16:42, Rose wrote:
>
> There's a saying among VHF / UHF'ers in reference
> to coax and connector losses that every .5db counts.
>
> 73! Ken - K0PP
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Jim Brown-10

Re: What is a dB worth was: Re: KX3 vs. K3 and other rigs?

In reply to this post by Pete Smith N4ZR

On 6/7/2011 6:14 AM, Pete Smith wrote:
> It is pretty widely accepted in contesting that an improvement in
> *either* receive or transmit capability of 1 dB will yield a useful
> increase in the number of QSOs over a 48-hour contest, even if it has an
> indiscernible effect on 99.5 percent of your contacts.

On the basis of statistical analysis of scores, one of the guys in our
contest club came up with the number that 1 dB is good for a 2.6%
increase in a Sweepstakes score. 3dB would be good for 1.026 x 1.026 x
1.026 = 8%, 7dB would be good for 20%. The advantage can show up in
several ways -- your ability to get over the other guy's noise, to hold
a frequency, to get answered sooner when there are multiple callers, to
pick up a rare multiplier.

It doesn't matter how you get the advantage -- better antenna, low loss
in the feedline, or power amp, and as you noted, it also helps to be
able to hear better, whether by reducing RX noise, using dedicated RX
antennas, choking noise sources, choking feedlines to reduce noise
pickup, exploding the chargers for power tools and mobility scooters,
etc. :)

73, Jim K9YC

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Eric Swartz - WA6HHQ

Re: What is a dB worth was: Re: KX3 vs. K3 and other rigs? [Thread already closed]

Administrator

These threads were closed earlier this morning. Please take the
discussion off-list.

73,
Eric
List moderator (Really! )

On 6/7/2011 11:26 AM, Jim Brown wrote:
> On 6/7/2011 6:14 AM, Pete Smith wrote:
>> It is pretty widely accepted in contesting that an improvement in
>> *either* receive or transmit capability of 1 dB will yield a useful
>> increase in the number of QSOs over a 48-hour contest, even if it has an
>> indiscernible effect on 99.5 percent of your contacts.
> On the basis of statistical analysis of scores, .html
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