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Re: Amplifier thoughts

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Ralph Parker-2

Re: Amplifier thoughts

I better post this before I'm too late.

I'd like:
All the features of my KPA500, plus
1500w output, 160 - 6m.
2 inputs.
2 outputs (or more. Manual switching is OK).
Built-in antenna tuner (good for 3:1 SWR).
Reasonably quiet fans.
Separate p/s, or remote control head (space considerations).
(I understand the difficulty of getting high power from the p/s to
the PA.)
I don't expect to carry it around, so weight is not a problem for me.
Expeditions can use the KPA500 :-)

When this amp is available, I'll sell amplifiers Ac and Am and buy one.
I'm keeping my KPA-500!

Ralph, VE7XF

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Paul Van Dyke

Amplifier thoughts

Ralph Parker said my list.....

1500w output, 160 - 6m.
2 inputs.
4 outputs (Manual switching is OK).
Built-in antenna tuner (good for 3:1 SWR).
Reasonably quiet fans.
Separate p/s, or remote control head (space considerations. :-)

Paul. KB9AVO

On Mar 28, 2017 4:40 PM, "Ralph Parker" <[hidden email]> wrote:

> I better post this before I'm too late.
>
> I'd like:
> All the features of my KPA500, plus
> 1500w output, 160 - 6m.
> 2 inputs.
> 2 outputs (or more. Manual switching is OK).
> Built-in antenna tuner (good for 3:1 SWR).
> Reasonably quiet fans.
> Separate p/s, or remote control head (space considerations).
> (I understand the difficulty of getting high power from the p/s to the
> PA.)
> I don't expect to carry it around, so weight is not a problem for me.
> Expeditions can use the KPA500 :-)
>
> When this amp is available, I'll sell amplifiers Ac and Am and buy one.
> I'm keeping my KPA-500!
>
> Ralph, VE7XF
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
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>

briancom

Re: Amplifier thoughts

KAT500 handles a much wider SWR range (like to about 10:1).

Why do you assume people are lucky enough to have antennas with no more
than a 3:1 SWR across the ham bands?

Yes, higher SWR's require beefed up components but welcome to the real
world.

73 de Brian/K3KO

On 3/28/2017 23:00 PM, Paul Van Dyke wrote:

> Ralph Parker said my list.....
>
> 1500w output, 160 - 6m.
> 2 inputs.
> 4 outputs (Manual switching is OK).
> Built-in antenna tuner (good for 3:1 SWR).
> Reasonably quiet fans.
> Separate p/s, or remote control head (space considerations. :-)
>
> Paul. KB9AVO
>
> On Mar 28, 2017 4:40 PM, "Ralph Parker" <[hidden email]> wrote:
>
>> I better post this before I'm too late.
>>
>> I'd like:
>> All the features of my KPA500, plus
>> 1500w output, 160 - 6m.
>> 2 inputs.
>> 2 outputs (or more. Manual switching is OK).
>> Built-in antenna tuner (good for 3:1 SWR).
>> Reasonably quiet fans.
>> Separate p/s, or remote control head (space considerations).
>> (I understand the difficulty of getting high power from the p/s to the
>> PA.)
>> I don't expect to carry it around, so weight is not a problem for me.
>> Expeditions can use the KPA500 :-)
>>
>> When this amp is available, I'll sell amplifiers Ac and Am and buy one.
>> I'm keeping my KPA-500!
>>
>> Ralph, VE7XF
>>
>> ______________________________________________________________
>> 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]
>>
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Dave AD6A

Re: Amplifier thoughts

I'd prefer to see the mythical KPA1500 support both a matching KAT1500 (same desk footprint as the amp, so it can sit underneath it neatly), as well as a new fully-weatherized remote tuner product (call it KART1500?) that can sit right at the antenna feedpoint.
VSWR tuning range for both should be 10:1 to 1:1 with no tuning gaps or compromises (I really don't mind paying the extra to achieve this).

I'd like the KPA1500 to have full on/off switching on the front panel, and USB rather than D-sub connectors on the rear panel.
At least TWO selectable radio source inputs and THREE selectable antenna output ports.

While we're on wish lists, I'd LOVE to see Elecraft produce a VHF/UHF/Microwave radio that looks and operates almost like the K3s with 144MHz, 220MHz, 440MHz, 1296MHz, 2400MHz, etc. (maybe optional modules on the upper bands). Separate antenna ports per band, 100W TX (maybe a bit less on the upper bands), all-mode, alpha-numeric labels for memories (a la Yaesu FTM-400XDR), click-mode main tuning dial selectable (like IC-7000), and a super-fast scan feature.

Don't want much, do I? ;)

Cheers es 73,
Dave AD6A

-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of brian
Sent: Tuesday, March 28, 2017 4:31 PM
To: [hidden email]
Subject: Re: [Elecraft] Amplifier thoughts

KAT500 handles a much wider SWR range (like to about 10:1).

Why do you assume people are lucky enough to have antennas with no more than a 3:1 SWR across the ham bands?

Yes, higher SWR's require beefed up components but welcome to the real world.

73 de Brian/K3KO

On 3/28/2017 23:00 PM, Paul Van Dyke wrote:

> Ralph Parker said my list.....
>
> 1500w output, 160 - 6m.
> 2 inputs.
> 4 outputs (Manual switching is OK).
> Built-in antenna tuner (good for 3:1 SWR).
> Reasonably quiet fans.
> Separate p/s, or remote control head (space considerations. :-)
>
> Paul. KB9AVO
>
> On Mar 28, 2017 4:40 PM, "Ralph Parker" <[hidden email]> wrote:
>
>> I better post this before I'm too late.
>>
>> I'd like:
>> All the features of my KPA500, plus
>> 1500w output, 160 - 6m.
>> 2 inputs.
>> 2 outputs (or more. Manual switching is OK).
>> Built-in antenna tuner (good for 3:1 SWR).
>> Reasonably quiet fans.
>> Separate p/s, or remote control head (space considerations).
>> (I understand the difficulty of getting high power from the p/s
>> to the
>> PA.)
>> I don't expect to carry it around, so weight is not a problem for me.
>> Expeditions can use the KPA500 :-)
>>
>> When this amp is available, I'll sell amplifiers Ac and Am and buy one.
>> I'm keeping my KPA-500!
>>
>> Ralph, VE7XF
>>
>> ______________________________________________________________
>> 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]
>>
> ______________________________________________________________
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> Post: mailto:[hidden email]
>
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> list: http://www.qsl.net/donate.html Message delivered to
> [hidden email]
>

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Matthew Cook

Re: Amplifier thoughts

In reply to this post by briancom

You can always use impedance transformers to bring your match back within
the "impedance range" of your tuner. These cost far less per unit price
than the components required to beef up an internal tuner to handle
impedance's of 500-800 ohms or more (or the conjugate) with a solid state
amp.

A simple 3:1 impedance transformation is not expensive in terms of
components and allows you to flatten out the band edges of a dipole or
beam. Out side of this your amplifier is asking you to pay attention.

For those wanting to use antenna with high impedance (or very low
impedance) feed point there are tuners already that will suit your purpose.
Thinking about that it would be nice if the KAT1500 could have some form
of tuner interface (like the Icom and Kenwoods) where an external tuner can
be activated, RF applied and held until the tuner releases the tune line.

In the real world as you put it capacitors look like door knobs and
inductors are large enough to stand in and everything is silver plated.
There's that pesky issue with the voltage being the square of the current
for a fixed impedance, it does take long for things to get nasty as you
increase the current by 1 or 2 amps at a time.

73

Matthew
VK5ZM

On 29 March 2017 at 10:00, brian <[hidden email]> wrote:

> KAT500 handles a much wider SWR range (like to about 10:1).
>
> Why do you assume people are lucky enough to have antennas with no more
> than a 3:1 SWR across the ham bands?
>
> Yes, higher SWR's require beefed up components but welcome to the real
> world.
>
> 73 de Brian/K3KO
>
>
> On 3/28/2017 23:00 PM, Paul Van Dyke wrote:
>
>> Ralph Parker said my list.....
>>
>> 1500w output, 160 - 6m.
>> 2 inputs.
>> 4 outputs (Manual switching is OK).
>> Built-in antenna tuner (good for 3:1 SWR).
>> Reasonably quiet fans.
>> Separate p/s, or remote control head (space considerations. :-)
>>
>> Paul. KB9AVO
>>
>> On Mar 28, 2017 4:40 PM, "Ralph Parker" <[hidden email]> wrote:
>>
>> I better post this before I'm too late.
>>>
>>> I'd like:
>>> All the features of my KPA500, plus
>>> 1500w output, 160 - 6m.
>>> 2 inputs.
>>> 2 outputs (or more. Manual switching is OK).
>>> Built-in antenna tuner (good for 3:1 SWR).
>>> Reasonably quiet fans.
>>> Separate p/s, or remote control head (space considerations).
>>> (I understand the difficulty of getting high power from the p/s to
>>> the
>>> PA.)
>>> I don't expect to carry it around, so weight is not a problem for me.
>>> Expeditions can use the KPA500 :-)
>>>
>>> When this amp is available, I'll sell amplifiers Ac and Am and buy one.
>>> I'm keeping my KPA-500!
>>>
>>> Ralph, VE7XF
>>>
>>> ______________________________________________________________
>>> 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
>> 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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>
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John Marvin

Re: Amplifier thoughts

In reply to this post by Paul Van Dyke

Put me down as a vote against a built-in antenna tuner. I prefer a
separate external tuner that integrates well with the amplifier. It
allows for a lot more configuration flexibility.

73
John
AC0ZG

On 3/28/2017 5:00 PM, Paul Van Dyke wrote:

Chris Tate - N6WM

Re: Amplifier thoughts

Perhaps an installable option would satisfy all...

-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of John Marvin
Sent: Tuesday, March 28, 2017 9:12 PM
To: [hidden email]
Subject: Re: [Elecraft] Amplifier thoughts

Put me down as a vote against a built-in antenna tuner. I prefer a separate external tuner that integrates well with the amplifier. It allows for a lot more configuration flexibility.

73
John
AC0ZG

On 3/28/2017 5:00 PM, Paul Van Dyke wrote:

> Ralph Parker said my list.....
>
> 1500w output, 160 - 6m.
> 2 inputs.
> 4 outputs (Manual switching is OK).
> Built-in antenna tuner (good for 3:1 SWR).
> Reasonably quiet fans.
> Separate p/s, or remote control head (space considerations. :-)
>
> Paul. KB9AVO
>
> On Mar 28, 2017 4:40 PM, "Ralph Parker" <[hidden email]> wrote:
>
>> I better post this before I'm too late.
>>
>> I'd like:
>> All the features of my KPA500, plus
>> 1500w output, 160 - 6m.
>> 2 inputs.
>> 2 outputs (or more. Manual switching is OK).
>> Built-in antenna tuner (good for 3:1 SWR).
>> Reasonably quiet fans.
>> Separate p/s, or remote control head (space considerations).
>> (I understand the difficulty of getting high power from the p/s
>> to the
>> PA.)
>> I don't expect to carry it around, so weight is not a problem for me.
>> Expeditions can use the KPA500 :-)
>>
>> When this amp is available, I'll sell amplifiers Ac and Am and buy one.
>> I'm keeping my KPA-500!
>>
>> Ralph, VE7XF
>>
>> ______________________________________________________________
>> 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
> 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]

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Jim Brown-10

Re: Amplifier thoughts

In reply to this post by briancom

On Wed,3/29/2017 11:47 AM, Ron D'Eau Claire wrote:
> An SWR approaching 10:1 means high RF voltages on a coaxial line at the voltage loops

Remember that the SWR on a transmission line, and thus the loss in the
line, is determined ENTIRELY by the match between the antenna and the
line, NOT between the line and the transmitter.

The SWR measured at the transmitter is a measure of the difference
between the impedance the transmitter WANTS to drive and the impedance
of the load connected to it. If that INDICATED SWR is high, a solid
state transmitter will "throttle itself back" to protect itself, but
that's not LOSS. The function of an antenna tuner is to make the
transmitter happy by giving it a load that it's designed for, so that it
can put out its full power.

For example, a long wire antenna of random length might be nowhere near
50 ohms resistive, so must be transformed to 50 ohms resistive so that
the transmitter can put power into it. Likewise, an antenna perfectly
matched to 75 ohm coax or 150 ohm twin lead has no excess loss in the
line but needs a matching network to make the transmitter happy. My
high dipoles (at 100 - 140 ft) are fed with 75 ohm coax to minimize the
loss in the line.

73, Jim K9YC

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Oliver Dröse

Re: Amplifier thoughts

In reply to this post by Paul Van Dyke

And please do away with the 15 dB amplification limit for all sales
outside the USA. Nobody else has that rule in place so we should not
suffer from it. ;-)

73, Olli

Contest, DX & radio projects: http://www.dh8bqa.de

Am 29.03.2017 um 01:00 schrieb Paul Van Dyke:

Rick WA6NHC-2

Re: Amplifier thoughts

In reply to this post by briancom

Or in my case, the use of ladder line (durned HOA infested area) to
handle the near 20:1 on 160M (better on most other bands) so that the
loss is from the tuner to the antenna, not the final.

My solution is that I'm moving to a location better suited for antennas,
far far away in a land called Idaho. ;-)

Rick wa6nhc

On 3/29/2017 11:47 AM, Ron D'Eau Claire wrote:

> An SWR approaching 10:1 means high RF voltages on a coaxial line at the voltage loops and high current flows at the current loops requiring a very heavy-duty transmission line - likely a nitrogen-filled hard line at 1.5 kW or, at the very least, a very heavy Teflon insulated line. In practice, it is usually the voltage breakdown that kills coax.
>
> Of course high SWR also means high losses between the amp and the antenna.
>
> The power ratings published by coax cable suppliers are based on a low SWR -- typically less than 1.5:1.
>
> The bottom line is that going QRO means a more careful design and installation of the entire antenna system.
>
> 73, Ron AC7AC
>
>
>
> -----Original Message-----
> From: Elecraft [mailto:[hidden email]] On Behalf Of brian
> Sent: Tuesday, March 28, 2017 4:31 PM
> To: [hidden email]
> Subject: Re: [Elecraft] Amplifier thoughts
>
> KAT500 handles a much wider SWR range (like to about 10:1).
>
> Why do you assume people are lucky enough to have antennas with no more than a 3:1 SWR across the ham bands?
>
> Yes, higher SWR's require beefed up components but welcome to the real world.
>
> 73 de Brian/K3KO
>
> ______________________________________________________________
> 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]

Ron Wilcox

Re: Amplifier thoughts

Idaho is a great place for our hobby. That is where I got my start in the
80's from Don KA7T. Good luck. I am excited about the chatter the last week
or so about our wishes for an amp. Hope it happens. There have been some
great ideas so far.

Today is a good day to have a Great Day!
73 Ron Wilcox KF7ZN

On Wed, Mar 29, 2017 at 4:07 PM, Rick WA6NHC <[hidden email]> wrote:

> Or in my case, the use of ladder line (durned HOA infested area) to handle
> the near 20:1 on 160M (better on most other bands) so that the loss is from
> the tuner to the antenna, not the final.
>
> My solution is that I'm moving to a location better suited for antennas,
> far far away in a land called Idaho. ;-)
>
> Rick wa6nhc
>
>
> On 3/29/2017 11:47 AM, Ron D'Eau Claire wrote:
>
>> An SWR approaching 10:1 means high RF voltages on a coaxial line at the
>> voltage loops and high current flows at the current loops requiring a very
>> heavy-duty transmission line - likely a nitrogen-filled hard line at 1.5 kW
>> or, at the very least, a very heavy Teflon insulated line. In practice, it
>> is usually the voltage breakdown that kills coax.
>>
>> Of course high SWR also means high losses between the amp and the antenna.
>>
>> The power ratings published by coax cable suppliers are based on a low
>> SWR -- typically less than 1.5:1.
>>
>> The bottom line is that going QRO means a more careful design and
>> installation of the entire antenna system.
>>
>> 73, Ron AC7AC
>>
>>
>>
>> -----Original Message-----
>> From: Elecraft [mailto:[hidden email]] On Behalf Of
>> brian
>> Sent: Tuesday, March 28, 2017 4:31 PM
>> To: [hidden email]
>> Subject: Re: [Elecraft] Amplifier thoughts
>>
>> KAT500 handles a much wider SWR range (like to about 10:1).
>>
>> Why do you assume people are lucky enough to have antennas with no more
>> than a 3:1 SWR across the ham bands?
>>
>> Yes, higher SWR's require beefed up components but welcome to the real
>> world.
>>
>> 73 de Brian/K3KO
>>
>> ______________________________________________________________
>> 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]
>>
>
> ______________________________________________________________
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> Post: mailto:[hidden email]
>
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>