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grounding K2

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Scott McDowell-4

grounding K2

Hello
Has anyone ever felt the need to ground their K2, and if so, where did you
connect the ground wire to the K2?
Thanks
Scott
N5SM
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Roger Stein-2

RE: grounding K2

Yes, good RF/safety practice, to the ground post on the back of the K2 provided for that purpose.
Roger
WA7BOC
k2 755
k3 75

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]]On Behalf Of Scott McDowell
Sent: Wednesday, April 16, 2008 11:19 AM
To: [hidden email]
Subject: [Elecraft] grounding K2

Hello
Has anyone ever felt the need to ground their K2, and if so, where did you
connect the ground wire to the K2?
Thanks
Scott
N5SM
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Ken Wagner K3IU

Re: grounding K2

Except that the grounding post is part of the KAT2 ATU which may not be
installed.
73, Ken K3IU
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Roger Stein wrote:

> Yes, good RF/safety practice, to the ground post on the back of the K2 provided for that purpose.
> Roger
> WA7BOC
> k2 755
> k3 75
>
> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]]On Behalf Of Scott McDowell
> Sent: Wednesday, April 16, 2008 11:19 AM
> To: [hidden email]
> Subject: [Elecraft] grounding K2
>
>
> Hello
> Has anyone ever felt the need to ground their K2, and if so, where did you
> connect the ground wire to the K2?
> Thanks
> Scott
> N5SM
> _______________________________________________
> Elecraft mailing list
> Post to: [hidden email]
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Gary D Krause

Re: grounding K2

It's very easy to put a small bolt in the hole on the back panel. That's what
I did and I don't have the antenna tuner. Like someone else said, it good
practice to ground it.

Gary, N7HTS

On Wed, 16 Apr 2008 15:00:55 -0400
Ken Wagner K3IU <[hidden email]> wrote:

> Except that the grounding post is part of the KAT2 ATU which may not be
>installed.
> 73, Ken K3IU
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Roger Stein wrote:
>> Yes, good RF/safety practice, to the ground post on the back of the K2
>>provided for that purpose.
>> Roger
>> WA7BOC
>> k2 755
>> k3 75
>>
>> -----Original Message-----
>> From: [hidden email]
>> [mailto:[hidden email]]On Behalf Of Scott McDowell
>> Sent: Wednesday, April 16, 2008 11:19 AM
>> To: [hidden email]
>> Subject: [Elecraft] grounding K2
>>
>>
>> Hello
>> Has anyone ever felt the need to ground their K2, and if so, where did you
>> connect the ground wire to the K2?
>> Thanks
>> Scott
>> N5SM
>> _______________________________________________
>> Elecraft mailing list
>> Post to: [hidden email]
>> You must be a subscriber to post to the list.
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>>
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Solosko, Robert B (Bob)

RE: grounding K2

In reply to this post by Ken Wagner K3IU

That's true, but all you need to do is get a matching 6-32 screw to fit
the K2's threaded hole for the ground post.

73
Bob W1SRB

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of Ken Wagner K3IU
Sent: Wednesday, April 16, 2008 3:01 PM
To: [hidden email]
Subject: Re: [Elecraft] grounding K2

Except that the grounding post is part of the KAT2 ATU which may not be
installed.
73, Ken K3IU
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Roger Stein wrote:
> Yes, good RF/safety practice, to the ground post on the back of the K2
provided for that purpose.

> Roger
> WA7BOC
> k2 755
> k3 75
>
> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]]On Behalf Of Scott McDowell
> Sent: Wednesday, April 16, 2008 11:19 AM
> To: [hidden email]
> Subject: [Elecraft] grounding K2
>
>
> Hello
> Has anyone ever felt the need to ground their K2, and if so, where did

> you connect the ground wire to the K2?
> Thanks
> Scott
> N5SM
> _______________________________________________
> Elecraft mailing list
> Post to: [hidden email]
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>
>

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N4LQ-2

Re: grounding K2

In reply to this post by Scott McDowell-4

No. Grounding a rig is a waste of time and actually endangers it. I unhook
the antenna when not in use.
If you can't resist having a "ground wire", put a knife switch in series
with it so you can disconnect it when not in use. Hooking your rig to a
ground rod separate from your house electrical ground produces a ground loop
and that current flows right through your rig! If your antenna system is at
DC ground potential, such as a ground mounted vertical, again, be sure to
unhook when not in use.
If you follow some suggestions I've read on these groups, your rig will have
a far better grounding system then the crummy 8' ground rod on your
electrical entrance. Therefore when that big lightning surge comes
along...Guess where it goes..It goes from every point in your house, right
through your K3 to that super duper ground system you installed. Don't fall
for it! Unhook the K3 and sleep easy. If you want to ground something,
unhook your antenna and ground it. Don't let the feed line dangle in mid
air. Hook it to that ground rod when your off the air. Let the lightning hit
the antenna and melt it. Grounding the antenna will at least help keep the
blast of current from jumping over to something more inviting! Just leave
the poor K3 out of the circuit.
Steve Ellington
[hidden email]
----- Original Message -----
From: "Scott McDowell" <[hidden email]>
To: <[hidden email]>
Sent: Wednesday, April 16, 2008 2:19 PM
Subject: [Elecraft] grounding K2

> Hello
> Has anyone ever felt the need to ground their K2, and if so, where did you
> connect the ground wire to the K2?
> Thanks
> Scott
> N5SM
> _______________________________________________
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Don Wilhelm-4

Re: grounding K2

In reply to this post by Scott McDowell-4

Scott,

There is no real need to ground the K2 itself. Ground the antenna
feedline shield for a better installation. The K2 would be grounded
through that coax connection.

I could go on and on about grounding, but in a nutshell, there are 3
types of grounds to consider:
1) AC Safety Ground - the K2 does not need one - but an AC power supply
should. A proper 3 wire household outlet should have this ground
connected to the mains entry point ground.
2) Lightning Surge ground - your antennas should have adequate
protection from lightning surges, but that requires an extensive
grounding system (see the PolyPhaser website for information).
IMPORTANT - any added ground system or ground rod MUST be connected to
the Utility Entry point ground rod with a heavy wire - #6 or larger
(required by NEC and important to protect you and your equipment should
an AC ground fault occur).
3) RF Ground - this one is a "horse of a different color". It is
unlikely that you will achieve an RF ground by making a connection to
Mother Earth - any wire you run off to a ground rod will be an odd
mulitple of a quarter-wave long at some frequencies, and will present a
high impedance at those frequencies (this is exactly the opposite of an
RF Ground). RF will seek its own zero-voltage (or ground point)
somewhere in the antenna system - for example, that point will be at the
midpoint of a balanced radiator. You challenge is to control the RF
Ground within your antenna system to avoid conducting RF back to the shack.

If you install a KAT2 or KAT100 or KPA100, there is a grounding terminal
provided on each of those options should you wish to attach a ground
wire. For the basic K2, one could add a ground terminal to the hole in
the top cover (the one that will be used for the KAT2 ground).

73,
Don W3FPR

Scott McDowell wrote:
> Hello
> Has anyone ever felt the need to ground their K2, and if so, where did you
> connect the ground wire to the K2?
> Thanks
> Scott
> N5SM
>
>
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Stephen W. Kercel

Re: grounding K2

In reply to this post by Scott McDowell-4

Scott:

If you do not have noticeable RF on the chassis, as you should not
have if you are using a dipole with low swr, the ground connection
does not do much for you. If you're running a random wire or Windom,
you might have RF getting back into the shack and some of it might
find its way back to the K2. Then you need an rf ground for the
chassis of the radio.

In that case you need as short and direct a path as possible to RF ground.

Remember that you have three distinctly different grounding problems,
with conflicting solutions.

1) The powerline safety ground. If your house wiring is up to code,
and if you are using a power supply whose AC input uses a three-wire
plug properly wired, you need do nothing further about this. CAVEAT:
Do NOT use the house wiring ground as an RF ground; you are very
likely to have a resonance at an HF ham frequency and this can cause
you all sorts of EMI problems. In my setup, I have MFJ ferrites on
the DC lead between my K2 and the power supply, and on the AC power
lead of my power supply.

2) Lightning ground. If you use polyphasers or a Wireman ground bus
or some other device to keep lightning out of the shack, that needs
to have its own ground rod. You want lightning-induced surges to have
as short and direct a path to ground as possible. CAVEAT: To meet
code, this ground rod must be bonded to your house wiring ground by
at least a #6 copper wire.

3) RF ground. There is no good RF ground. At HF frequencies any
finite wire has non-trivial inductive reactance. According to an
Army-Air Force study (that I often hear mentioned, but for which I
cannot find the report), the least unacceptable HF RF ground is a
wire a half wave length long at your lowest frequency, buried one
inch below ground surface, and connected to 1 foot ground rods spaced
every 8 feet. Deep burial of the wire or longer ground rods are no
help because HF RF only penetrates about 3 inches into average
ground. If you cannot run the wire in a straight line, a meandering
path will do. For safety reasons the wire should be #6 copper. To
meet code this wire should be bonded to your house ground via #6
copper wire. To keep the RF out of the house ground, use ferrites on
the bonding wire very near its connection to the RF ground wire. The
ferrites will not interfere with lightning or electrical fault
current passing through the bond wire; most of their energy is well
below 1 MHz, and the MFJ (and similar) ferrites start to roll off
just below HF. CAVEAT: At HF frequencies, ferrites such as MFJ have
2-3 dB attenuation; you need to use at least 6 ferrites to get any
useful reduction in undesired RF.

If you do not use an external antenna tuner, the K2 chassis should be
connected to the RF ground by as short and direct a wire as possible.
If you use an external tuner the tuner chassis should be connected to
the RF ground by as short and direct a wire as possible. In this case
if you put 6 ferrite beads on the coax between the K2 and the tuner,
the combination of the tuner grounding and the ferrites should keep
RF off the chassis of the K2. In that case, you might want to leave
the K2 chassis ungrounded to avoid forming a ground loop.

FINAL CAVEAT: As with antennas, RF grounding is as much witchcraft
and magic as it is physics. The practices listed above work most of
the time but not always. The grounding system of any specific station
might need to be tweaked to eliminate EMI and other problems. For
safety reasons the ground system should be code compliant. Code
compliance will not solve any EMI problems or make your station get
out better, but it will keep you from getting killed.

73,

Steve Kercel
AA4AK

At 02:19 PM 4/16/2008, Scott McDowell wrote:

>Hello
>Has anyone ever felt the need to ground their K2, and if so, where did you
>connect the ground wire to the K2?
>Thanks
>Scott
>N5SM
>_______________________________________________
>Elecraft mailing list
>Post to: [hidden email]
>You must be a subscriber to post to the list.
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Gary D Krause

Re: grounding K2

In reply to this post by N4LQ-2

Okay. But, I believe there are other reasons to ground your rig other than
lightning strikes. I certainly don't leave my antenna connected to any of my
rigs, grounded or not.

Gary, N7HTS

On Wed, 16 Apr 2008 15:13:03 -0400
"n4lq" <[hidden email]> wrote:

> No. Grounding a rig is a waste of time and actually endangers it. I unhook
>the antenna when not in use.
> If you can't resist having a "ground wire", put a knife switch in series
>with it so you can disconnect it when not in use. Hooking your rig to a
>ground rod separate from your house electrical ground produces a ground loop
>and that current flows right through your rig! If your antenna system is at
>DC ground potential, such as a ground mounted vertical, again, be sure to
>unhook when not in use.
> If you follow some suggestions I've read on these groups, your rig will have
>a far better grounding system then the crummy 8' ground rod on your
>electrical entrance. Therefore when that big lightning surge comes
>along...Guess where it goes..It goes from every point in your house, right
>through your K3 to that super duper ground system you installed. Don't fall
>for it! Unhook the K3 and sleep easy. If you want to ground something, unhook
>your antenna and ground it. Don't let the feed line dangle in mid air. Hook
>it to that ground rod when your off the air. Let the lightning hit the
>antenna and melt it. Grounding the antenna will at least help keep the blast
>of current from jumping over to something more inviting! Just leave the poor
>K3 out of the circuit.
> Steve Ellington
> [hidden email]
> ----- Original Message ----- From: "Scott McDowell" <[hidden email]>
> To: <[hidden email]>
> Sent: Wednesday, April 16, 2008 2:19 PM
> Subject: [Elecraft] grounding K2
>
>
>> Hello
>> Has anyone ever felt the need to ground their K2, and if so, where did you
>> connect the ground wire to the K2?
>> Thanks
>> Scott
>> N5SM
>> _______________________________________________
>> Elecraft mailing list
>> Post to: [hidden email]
>> You must be a subscriber to post to the list.
>> Subscriber Info (Addr. Change, sub, unsub etc.):
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>> Elecraft web page: http://www.elecraft.com
>>
>>
>> --
>> No virus found in this incoming message.
>> Checked by AVG.
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>> 9:34 AM
>>
>>
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Charly

RE: grounding radios

I have operated transceivers with no ground, with a poor ground, and a good one. I never could tell the difference in

over 50 years of operating at scores of locations. I had RF lip burns on a mic grounded to a good ground, and I have

had no RF problems at all on fourteenth floor with no ground ... even not on the electrical supply socket.

Today, I have one ground rod and one ground run to the house electrical box WHICH IS FED BY ONLY TWO

230VAC WIRES. So far, so good.

Lightning.... unplug everything and keep the ant/rotor wire entry point far away from ur radio. I had good success

with a 1000 foot rhombic by putting the feed line end out on the grass when not in use 10 ft from house.... Was ok,

but burned some grass around the end during a storm (grass was wet and green). I have done daisy chain gnds and

single point systems and could not tell the difference. Thems the facts for me.

GL, 73

Charles Harpole

[hidden email]

> From: [hidden email]
> Subject: Re: [Elecraft] grounding K2
> To: [hidden email]
> Date: Wed, 16 Apr 2008 13:23:05 -0600
>
> Okay. But, I believe there are other reasons to ground your rig other than
> lightning strikes. I certainly don't leave my antenna connected to any of my
> rigs, grounded or not.
>
> Gary, N7HTS
>
>
> On Wed, 16 Apr 2008 15:13:03 -0400
> "n4lq" <[hidden email]> wrote:
> > No. Grounding a rig is a waste of time and actually endangers it. I unhook
> >the antenna when not in use.
> > If you can't resist having a "ground wire", put a knife switch in series
> >with it so you can disconnect it when not in use. Hooking your rig to a
> >ground rod separate from your house electrical ground produces a ground loop
> >and that current flows right through your rig! If your antenna system is at
> >DC ground potential, such as a ground mounted vertical, again, be sure to
> >unhook when not in use.
> > If you follow some suggestions I've read on these groups, your rig will have
> >a far better grounding system then the crummy 8' ground rod on your
> >electrical entrance. Therefore when that big lightning surge comes
> >along...Guess where it goes..It goes from every point in your house, right
> >through your K3 to that super duper ground system you installed. Don't fall
> >for it! Unhook the K3 and sleep easy. If you want to ground something, unhook
> >your antenna and ground it. Don't let the feed line dangle in mid air. Hook
> >it to that ground rod when your off the air. Let the lightning hit the
> >antenna and melt it. Grounding the antenna will at least help keep the blast
> >of current from jumping over to something more inviting! Just leave the poor
> >K3 out of the circuit.
> > Steve Ellington
> > [hidden email]
> > ----- Original Message ----- From: "Scott McDowell" <[hidden email]>
> > To: <[hidden email]>
> > Sent: Wednesday, April 16, 2008 2:19 PM
> > Subject: [Elecraft] grounding K2
> >
> >
> >> Hello
> >> Has anyone ever felt the need to ground their K2, and if so, where did you
> >> connect the ground wire to the K2?
> >> Thanks
> >> Scott
> >> N5SM
> >> _______________________________________________
> >> Elecraft mailing list
> >> Post to: [hidden email]
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> >>
> >>
> >> --
> >> No virus found in this incoming message.
> >> Checked by AVG.
> >> Version: 7.5.524 / Virus Database: 269.23.0/1381 - Release Date: 4/16/2008
> >> 9:34 AM
> >>
> >>
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Rick Dettinger-3

Re: grounding K2

In reply to this post by Roger Stein-2

If I remember correctly, the base K2 came without the ground screw.
Its been a long time. I think the ground screw came with the ATU.
The K1 doesn't have a ground screw, even with the ATU. I am confused
about the use of an RF ground with a balanced antenna. One of the
advantages of a balanced antenna, verses an antenna that works with a
ground such as a vertical, is efficiency. If I use an RF ground with
a balanced antenna, am I losing efficiency. Especially if the ground
is mediocre? I don't want to put down 60 radials for my center fed
doublet. When I used my K1 or K2 with a battery and a balanced
antenna, I had confidence that most of the power was getting
radiated. Now I have a K3-100 with an Astron 35 M power supply and I
am wondering if that has changed. The 35 M schematic shows that the
13.8v DC terminal is connected to the 120v AC supply system ground.
This is continuous, overhead and underground, to the substation ground
mat. This doesn't sound too bad for a 160 M vertical, however, I
can't decide what effect this has on my CF doublet. Am I sending RF
all over the neighborhood on the power lines? Is this why a BALUN is
needed? Is my antenna efficiency and pattern different than when I
used battery power? If I use the doublet and a BALUN, what do I use
the ground screw for? It would be redundant to attach it to the AC
ground as this is done thru the 13.0v supply cable.

73
Rck Dettinger K7MW

On Apr 16, 2008, at 11:50 AM, Roger Stein wrote:

> Yes, good RF/safety practice, to the ground post on the back of the
> K2 provided for that purpose.
> Roger
> WA7BOC
> k2 755
> k3 75
>
> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]]On Behalf Of Scott McDowell
> Sent: Wednesday, April 16, 2008 11:19 AM
> To: [hidden email]
> Subject: [Elecraft] grounding K2
>
>
> Hello
> Has anyone ever felt the need to ground their K2, and if so, where
> did you
> connect the ground wire to the K2?
> Thanks
> Scott
> N5SM
> _______________________________________________
> Elecraft mailing list
> Post to: [hidden email]
> You must be a subscriber to post to the list.
> Subscriber Info (Addr. Change, sub, unsub etc.):
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Don Wilhelm-4

Re: grounding K2

Rick (long answer),

You are most likely mixing RF ground with a 'Mother Earth' ground. They
are quite different. The main reason is that RF does not behave like
low frequency AC or DC. You are not alone - that fact seems to mystify
and confuse many, many hams. I will try to give a conceptual
explanation. First understand that I use RF Ground as any point where
the RF voltage is zero (note that the RF current will be a maximum at
that same point). No other concept of RF ground has ever made any
sense to me.

With a balanced dipole antenna (center fed doublet), a point of RF
ground will occur at the midpoint of the center feed. That is where the
RF voltage crosses zero. If the radiator is fed with a parallel
transmission line, the currents on the two conductors will be equal an
opposite all along the feedline, so that effective RF Ground point is
carried all the way back to the shack along the transmission line.

If one uses coax to feed the antenna, a similar situation exists
*inside* the coax - due to skin effect, the inside of the coax shield
can be considered as a separate wire than the outside of the shield.
The currents on the center conductor and the inside of the shield will
be balanced (just like in the parallel transmission line). The problem
with coax is at the junction of the radiator and the shield. The RF
voltage (and current) on the inside of the shield sees two conductors at
that junction 1) the antenna wire, and 2) the outside of the coax
shield. A current balun installed at the antenna feedpoint will place a
high impedance on the outside of the coax shield while not interfering
with the balanced currents between the center conductor and the inside
of the shield. So, RF ground is maintained inside the coax - it is a
zero potential point that can be visualized as being midway between
those conductors. The item that seems to cause the most confusion is
that the coax shield can be at ground potential for DC and low frequency
AC, but it is *not* at ground potential for RF.

So, you do not need to create an RF ground for your dipole - it already
exists.

For a vertical with an elevated ground plane, a similar RF ground exists
midway between the vertical radiator and the ground plane (yes, the
ground wires radiate and are part of the antenna system - cancellation
of the ground wire radiation must be by the physical orientation so the
radiation cancels due to phase relationships). If a vertical radiator
is ground mounted, the earth takes the place of the ground plane - and
actual earth is not a really good conductor of RF, so we usually augment
that conduction by burying a lot of radials, the lengths are not
critical in those installations because we just want to improve the RF
characteristics of the real earth.

Bottom line is that I make the statement that an actual RF ground is a
property of the antenna system and is not to be equated to a Mother
Earth ground.

73,
Don W3FPR

Rick Dettinger wrote:

> If I remember correctly, the base K2 came without the ground screw.
> Its been a long time. I think the ground screw came with the ATU.
> The K1 doesn't have a ground screw, even with the ATU. I am confused
> about the use of an RF ground with a balanced antenna. One of the
> advantages of a balanced antenna, verses an antenna that works with a
> ground such as a vertical, is efficiency. If I use an RF ground with
> a balanced antenna, am I losing efficiency. Especially if the ground
> is mediocre? I don't want to put down 60 radials for my center fed
> doublet. When I used my K1 or K2 with a battery and a balanced
> antenna, I had confidence that most of the power was getting radiated.

Stephen W. Kercel

Re: grounding K2

In reply to this post by Rick Dettinger-3

Rick:

See interposed comments.

73

Steve Kercel
AA4AK

At 05:00 PM 4/16/2008, Rick Dettinger wrote:
>If I remember correctly, the base K2 came without the ground screw.
>Its been a long time. I think the ground screw came with the ATU.

*******************
I have a K2/100 with no ATU. It came with a ground screw.
*******************

>The K1 doesn't have a ground screw, even with the ATU. I am confused
>about the use of an RF ground with a balanced antenna.

******************
If the antenna were perfectly balanced there would be zero RF ground
current, and the RF ground impedance would not matter. In many
dipole/doubet installations the antenna is sort of balanced, and the
ground current is not exactly zero, but close enough that it causes
no noticeable problems.
*******************

>One of the
>advantages of a balanced antenna, verses an antenna that works with a
>ground such as a vertical, is efficiency.

*********************
Do not confuse these two different kinds of grounds. The RF ground
provides a path to remote earth for those pesky unbalanced currents.
A radial system on a ground mounted vertical is an integral part of
the antenna, that just happens to be slightly under ground.

The reason that a dipole is more efficient than a ground mounted
vertical is that for the ground mounted vertical, half the antenna is
immersed in a lossy medium.
*********************

>If I use an RF ground with
>a balanced antenna, am I losing efficiency.

*****************
No, your balanced doublet is located some distance away from the
lossy medium. The RF ground is keeping things from going wrong (such
as smoke detectors going off in step with your keying), but has
little influence on the efficiency of your balanced antenna.
*****************

>Especially if the ground
>is mediocre? I don't want to put down 60 radials for my center fed
>doublet.

*******************
You are correct. That would be an absolute waste.
*******************

>When I used my K1 or K2 with a battery and a balanced
>antenna, I had confidence that most of the power was getting
>radiated. Now I have a K3-100 with an Astron 35 M power supply and I
>am wondering if that has changed.

*****************
It is very unlikely anything has changed. Remember, it is extremely
poor practice to use your house ground as an RF ground, and wise
practice to put some ferrites on your power supply leads just to be
sure that no RF sneaks into hour house ground via the power supply.
If you are worried about RF getting into your house ground via the
power supply put six MFJ-701 ferrites on your power supply lead.
Simply run both the positive and negative wires through the hole in
the ferrite.
*****************

>The 35 M schematic shows that the
>13.8v DC terminal is connected to the 120v AC supply system ground.
>This is continuous, overhead and underground, to the substation ground
>mat. This doesn't sound too bad for a 160 M vertical, however, I
>can't decide what effect this has on my CF doublet.

******************
The effect is that somewhere in your house ground wiring, part of it
might resonate at your operating frequency and cause you all sorts of
problems, as manifested by bizarre behavior in other household
electronics such as digital clocks and telephones.

You'll never see the substation ground; the very large inductive
reactance of the intervening wires will effectively isolate you from it.
******************

>Am I sending RF
>all over the neighborhood on the power lines?

**************
Unlikely, see above.
*************

>Is this why a BALUN is
>needed?

*****************
RF in the shack is a problem sometimes (a lot less often than the
people selling them would have you think) mitigated by baluns. A
bigger problem is that radiation from the feedline (which baluns
minimize) can perturb the radiation pattern of a directional antenna.
That is why most beam antennas include a balun in the package.
*****************

>Is my antenna efficiency and pattern different than when I
>used battery power?

****************
Extremely unlikely
***************

>If I use the doublet and a BALUN, what do I use
>the ground screw for?

*****************
Unless you have "RF in the shack" or inexplicable EMI problems
somewhere in the house, leave it alone.
*****************

>It would be redundant to attach it to the AC
>ground as this is done thru the 13.0v supply cable.

***************
You will be a happier person if you avoid connecting the ground screw
of the radio to your house ground.
***************

>73
>Rck Dettinger K7MW
>
>
>On Apr 16, 2008, at 11:50 AM, Roger Stein wrote:
>>Yes, good RF/safety practice, to the ground post on the back of the
>>K2 provided for that purpose.
>>Roger
>>WA7BOC
>>k2 755
>>k3 75
>>
>>-----Original Message-----
>>From: [hidden email]
>>[mailto:[hidden email]]On Behalf Of Scott McDowell
>>Sent: Wednesday, April 16, 2008 11:19 AM
>>To: [hidden email]
>>Subject: [Elecraft] grounding K2
>>
>>
>>Hello
>>Has anyone ever felt the need to ground their K2, and if so, where
>>did you
>>connect the ground wire to the K2?
>>Thanks
>>Scott
>>N5SM
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PaulF

K3 Katie-gram received for Nov 7 order

My Katie-gram arrived today for the K3/100 kit. It was ordered Nov 7 and is
scheduled to ship in 7-10 days.

Backordered items: 1.8 filter, DVR, and 2nd Rcvr

73,
Paul
K5ESW
Raleigh, NC
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