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Phil Hystad-3

Re: P3 ship date

I hope so because I haven't received my P3 yet.

On Jul 23, 2010, at 01:18 PM, W4CCS <[hidden email]> wrote:

> Sorry if I missed a thread on this, but did Elecraft miss the July 17
> proposed ship date for the P3..??
>
> W4CCS
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Don Cunningham

Re: P3 ship date

In reply to this post by W4CCS

Yes, Eric's last update said first shipments in the 7/26-7/30 range. 5
to 6 weeks to clear the backlog. We're all anxious for a new update though
:>)
73,
Don, WB5HAK

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hf4me

Re: P3 ship date

In reply to this post by Phil Hystad-3

According to the status I saw 10 days ago, there was a 1-2 week delay from
one of the suppliers and they had hoped for arrival of the parts today and
first CUSTOMER ship for 26-30th. That is NEXT week !!! The testers have
some now.

"Can't" wait.

73, Jim

----- Original Message -----
From: "Phil Hystad" <[hidden email]>
To: "W4CCS" <[hidden email]>
Cc: <[hidden email]>
Sent: Friday, July 23, 2010 3:21 PM
Subject: Re: [Elecraft] P3 ship date

>I hope so because I haven't received my P3 yet.
>
>
> On Jul 23, 2010, at 01:18 PM, W4CCS <[hidden email]> wrote:
>
>> Sorry if I missed a thread on this, but did Elecraft miss the July 17
>> proposed ship date for the P3..??
>>
>> W4CCS
>> ______________________________________________________________
>> 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
> ______________________________________________________________
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W8JI

Re: Balun Questions

In reply to this post by Brett Howard

<<<Interesting enough his high power one uses two cores and appears to be
made the same as the "budget" one that is wound on one core... Seems
like stacking them on top of one another is going to just couple them
and hinder your isolation but maybe I'm wrong there....>>>

Hi Bret,

With two toroids spaced with air gap, coupling is much less between the
transmission lines. The lower the mutual coupling the better behaved the
balun is into balanced loads or less that perfectly balanced loads. I expect
two toroids with some air gap between them to be acceptably isolated,
although it would be best to confirm this.

The budget balun however is a mistake. It is electrically impossible for
that balun to feed a real load, like an antenna, with balanced currents. It
will work just dandy on a single small floating resistor, but that is not a
balanced load. A single small floating resitor has no defined balance at
all, because it has nearly infinite common mode impedance.

I'll have an article out in a week or so, maybe less, that explains this all
in detail.

73 Tom

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ussv dharma

Re: K3 recorder

In reply to this post by Bob Naumann W5OV

I do use headphones 24/7...it is just that using the recorder and getting it to playback while transmitting is overwhelming....I gave up.

Great Grandmaw Susan (Ex Msgt....got a problem sonny?_

If you don't change direction you WILL arrive exactly where you're headed!! Susan Meckley, Skipper W7KFI-mm AFA9SM USSV DHARMA

--- On Fri, 7/23/10, [hidden email] <[hidden email]> wrote:

> From: [hidden email] <[hidden email]>
> Subject: Re: [Elecraft] K3 recorder
> To: "David Pratt" <[hidden email]>
> Cc: "ussv dharma" <[hidden email]>, "elecraft" <[hidden email]>
> Date: Friday, July 23, 2010, 8:18 AM
>
> You can hear what you're transmitting with the monitor
> feature.
>
> Wait - I think I know what the issue is - I'm guessing that
> you are not
> using headphones, so you don't want the monitor on except
> when playing
> back a DVR recording.
>
> My mistake.
>
> I presumed you would be using headphones to get the best
> results from your
> K3's receiver.
>
> 73,
>
> Bob W5OV
> (always uses headphones)
>
>
>
> > Don't worry about it, Susan. Wayne has on his
> 'list' to include some
> > refinements to the KDVR3 to enable us to actually hear
> what is being
> > transmitted. Until then, my own KDVR3 is on
> hold.
> >
> > 73 de David G4DMP
> >
> > In a recent message, ussv dharma <[hidden email]>
> wrote ...
> >>
> >>I have finally just given up. I no longer try
> to use the K3 recorder
> >>to show the other ham how his signal
> sounds.....just too darned
> >>confusing.
> >>
> >>Great Grandmaw Susan
> > --
> > David G4DMP
> > Leeds, England, UK
> > ------
> >
> >
> >
> >
> ______________________________________________________________
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> >
>
>
>

Gary Hinson

Re: Balun Questions

In reply to this post by Brett Howard

1:1 baluns are dead easy to make: simply wind a few turns of the antenna end
of your coax feeder around a suitable toroid core before connecting it to
your balanced antenna. I use the FT241 cores from Amidon Associates, the
"k" type for 160-40m bands or "61" mix for the higher HF bands. I can
easily get 10 turns of RG58 coax on a core, and these seem to work nicely
for me [I don't have the knowledge, test gear or patience to test them on
the bench, but depend on Mr Sevick's advice in his book.] I've had no
problems running our legal limit of 500W into these.

4:1 baluns require a just bit more work. These are made by winding a
bifilar coil using two tightly-strapped wires of the appropriate size and
type on a suitable core - a chunky T400A2 powdered iron core in my QRO balun
(capable of well over the legal limit I'm sure), with an SO239 connector for
the coax.

All my baluns use watertight plastic boxes with rubber gaskets to seal their
lids, stainless-steel hardware for the antenna connections (S/S wing nuts
make them much easier to connect up antennas in the field), and some care to
ensure they remain watertight in use (e.g. I use superglue to wick into the
gaps and seal both SO239s and antenna connections to the case, plus
self-amalgamating rubber tape on any PL259-SO239 connections with a layer of
ordinary electrical tape over the outside to cut down UV damage to the
rubber).

For LF dipoles that will put a lot of stress on the center connections, I
use an army-surplus ceramic open wire feeder spreader for strain relief on
the antenna wire, using tie-wraps to hold the spreader to the box through
the box corner mounting holes which don't penetrate the sealed section, at
least in the boxes I can buy here.

Even buying everything new and importing the cores from the US, they are
*much* cheaper than any commercial units of similar power-handling capacity
that I can obtain, here in ZL anyway. As a very happy customer, I have no
hesitation in recommending Amidon www.AmidonCorp.com

There are photos etc. on my site at
http://www.g4ifb.com/html/homebrew.html#Baluns and I'd be happy to answer
any queries as best I can.

73,
Gary ZL2iFB

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David Pratt

Re: K3 recorder

In reply to this post by David Pratt

The problem, Deni, is that if you are using a speaker and have MON set
to zero, you are unable to hear what is being retransmitted.
Consequently, it is easy to retransmit the wrong stuff, including
callsigns, which would be against licence conditions.

I understand that it is the intention for a firmware upgrade to include
the facility for the MON to be set to a value to enable monitoring of
outgoing recordings even though it is normally set at zero.

Maybe Wayne would confirm that this is still on the 'list'?

73 de David G4DMP

In a recent message, Deni <[hidden email]> wrote ...

>
>Hi David, as it happens I have just today ordered the KDVR3.
>Is there some issue with it's use?
>
>What "refinements" are in the pipeline?
>Is this going to be a hardware issue? If so I'll put my order on hold too.
>However if it's just software updates, no problem with that.
>I guess lots of people are using this unit already.
>
>Can you give me any info?

--
David G4DMP
Leeds, England, UK
------

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Deni F5VJC

Re: K3 recorder

Thanks for the info David.
I understand your reasoning, but for me this will not be a problem.

73, Deni
F5VJC
K3# 325

David Pratt wrote:

> The problem, Deni, is that if you are using a speaker and have MON set
> to zero, you are unable to hear what is being retransmitted.
> Consequently, it is easy to retransmit the wrong stuff, including
> callsigns, which would be against licence conditions.
>
> I understand that it is the intention for a firmware upgrade to include
> the facility for the MON to be set to a value to enable monitoring of
> outgoing recordings even though it is normally set at zero.
>
> Maybe Wayne would confirm that this is still on the 'list'?
>
> 73 de David G4DMP
>
> In a recent message, Deni <[hidden email]> wrote ...
>>
>> Hi David, as it happens I have just today ordered the KDVR3.
>> Is there some issue with it's use?
>>
>> What "refinements" are in the pipeline?
>> Is this going to be a hardware issue? If so I'll put my order on hold
>> too.
>> However if it's just software updates, no problem with that.
>> I guess lots of people are using this unit already.
>>
>> Can you give me any info?

Geoffrey Downs-3

Re: K3 recorder

In reply to this post by ussv dharma

Good luck with the KDVR3, Deni. It works very well, but IMHO David is
right - it would be a great convenience to be able *automatically* to hear a
recording that is being transmitted. Wayne's response is eagerly awaited
here!

73 to all

Geoff
G3UCK

----- Original Message -----
From: "Deni" <[hidden email]>
Subject: Re: [Elecraft] K3 recorder

> Thanks for the info David.
> I understand your reasoning, but for me this will not be a problem.
>
> 73, Deni
> F5VJC
> K3# 325
>
>
> David Pratt wrote:
>> The problem, Deni, is that if you are using a speaker and have MON set
>> to zero, you are unable to hear what is being retransmitted.
>> Consequently, it is easy to retransmit the wrong stuff, including
>> callsigns, which would be against licence conditions.
>>
>> I understand that it is the intention for a firmware upgrade to include
>> the facility for the MON to be set to a value to enable monitoring of
>> outgoing recordings even though it is normally set at zero.
>>
>> Maybe Wayne would confirm that this is still on the 'list'?
>>
>> 73 de David G4DMP

Jim Brown-10

Re: Balun Questions

In reply to this post by Brett Howard

On Fri, 23 Jul 2010 11:53:33 -0700, Brett Howard wrote:

>Interesting enough his high power one uses two cores and appears to be
>made the same as the "budget" one that is wound on one core... Seems
>like stacking them on top of one another is going to just couple them
>and hinder your isolation but maybe I'm wrong there....

No, the only coupling between chokes wound on different ferrite cores
that provide a complete path for current (like a toroid) is the stray
capacitance that results from their physical proximity. Virtually ALL
of the flux stays in the ferrite core -- there is virtually NO leakage
flux (that is, coupling between coils wound on different toroids).

This is generally true of ALL coils wound on closed ferrite paths.
Leakage flux (and thus coupling outside the core) occurs when the
ferrite does NOT complete the path (for example, a coil wound on a
ferrite bar, also known as a loopstick receiving antenna).

If you want a very good 4:1 impedance tranforming balun for less than
about 500 watts, consider building one from two of the 12-turn or 14-
turn THHN chokes shown in my tutorial. Each choke is wound on a #31
2.4-inch o.d. core. Total cost about $20 (two cores plus some wire and
connectors).

73, Jim Brown K9YC

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Brett Howard

Re: Balun Questions

Where be your tutorial? I've got a couple 4" #2 cores that I was
thinking of using... Not sure if it'll be the right material but they
sure are big enough that I shouldn't have to worry about power
handling! ;)

It'll probably be a bit before I get to building the Balun project. I'm
in the process of building a full few sets of W3NQN band pass filters.
So far I've built one all the way through and I've got 82dB of second
harmonic rejection. Now I'm in batch mode and I've just finished
getting the connectors on a bunch more project boxes. Also about 91
cores just arrived on the front door step! ;)

Then on top of that I'm working on making a band decoder
(http://k3decoder.googlecode.com). Needless to say I'm keeping busy
with those projects and the full time job. ;)

~Brett (N7MG)

On Fri, 2010-07-30 at 11:13 -0700, Jim Brown wrote:

> On Fri, 23 Jul 2010 11:53:33 -0700, Brett Howard wrote:
>
> >Interesting enough his high power one uses two cores and appears to be
> >made the same as the "budget" one that is wound on one core... Seems
> >like stacking them on top of one another is going to just couple them
> >and hinder your isolation but maybe I'm wrong there....
>
> No, the only coupling between chokes wound on different ferrite cores
> that provide a complete path for current (like a toroid) is the stray
> capacitance that results from their physical proximity. Virtually ALL
> of the flux stays in the ferrite core -- there is virtually NO leakage
> flux (that is, coupling between coils wound on different toroids).
>
> This is generally true of ALL coils wound on closed ferrite paths.
> Leakage flux (and thus coupling outside the core) occurs when the
> ferrite does NOT complete the path (for example, a coil wound on a
> ferrite bar, also known as a loopstick receiving antenna).
>
> If you want a very good 4:1 impedance tranforming balun for less than
> about 500 watts, consider building one from two of the 12-turn or 14-
> turn THHN chokes shown in my tutorial. Each choke is wound on a #31
> 2.4-inch o.d. core. Total cost about $20 (two cores plus some wire and
> connectors).
>
> 73, Jim Brown K9YC
>
>
> ______________________________________________________________
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Jim Brown-10

Re: Balun Questions

On Fri, 30 Jul 2010 19:35:50 -0700, Brett Howard wrote:

>Where be your tutorial?

http://audiosystemsgroup.com/RFI-Ham.pdf

>I've got a couple 4" #2 cores

Cores are NOT mix and match. It took me YEARS to find this particular sweet
spot. If you want a decent balun, you must either follow the instructions
based on my research, or do five years of your own work, or send lots of
bucks to DXE. :)

73, Jim K9YC

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