Elecraft › [QRO]

News from Visalia! (:-))

Classic

List

Threaded

60 messages Options

123

Don Wilhelm-4

Re: KPA500

No need for a tuner here, all the antennas are resonant - and it has to
be that way so I can locate the antennas out of view from the house or
when coming up the driveway (XYL says so), and in her eye, seeing an
open wire or ladder line feeders is as bad or worse than antenna wires,
so I run 150 ft. long coax lines out through conduit and through the
attic of a large garage building to the entry point of the antenna
field. It keeps peace in the family :-) .

73,
Don W3FPR

Guy Olinger K2AV wrote:

> Starting up another unconfirmed rumor mill are we, or did I miss some
> official statement?
>
> 73, Guy
>
> On Fri, Apr 16, 2010 at 5:53 PM, John Harper <[hidden email]> wrote:
>
>> I guess the next sensible kit from E would be a 500 watt capable
>> autotuner.....
>>
>> John Harper AE5X
>> http://www.ae5x.com/blog
>>
>>
>

Richard Thorne

Re: KPA500

In reply to this post by John Harper AE5X

And a remote one at that...

Rich - N5ZC

On 4/16/2010 4:53 PM, John Harper wrote:

> I guess the next sensible kit from E would be a 500 watt capable
> autotuner.....
>
> John Harper AE5X
> http://www.ae5x.com/blog
>
>
>
>
> ______________________________________________________________
> 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
>
>

Doug Faunt N6TQS +1-510-655-8604

Re: KPA500

In reply to this post by Roger Dallimore-2

I'm headed out for dinner, so this is probably redundant, but I don't
have time to read the mail queue.
It weighs 10 kilos, does NOT have a built in tuner, but DOES have a
built-in linear power supply good for all common mains specs.

73, doug

Date: Fri, 16 Apr 2010 20:42:05 +0100
From: Roger Dallimore <[hidden email]>

Fantastic news! Can't wait to find out more.

73
Roger MW0IDX

K3 #191
K2 #2724
KX1 #416
KPA500 #???
>
> Of perhaps as much interest is the new KPA500 amplifier
> that's just appeared on the table. All I can tell you is that
> it's somewhat weighty and has a switching supply built
> into the cabinet. The cabinet is the same size as a K3,
> so Rose won't need to design a new cover.
>
>

______________________________________________________________
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

______________________________________________________________
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

Arie Kleingeld PA3A-2

Re: KPA500

The fine thing about the QRP K2 and the K3 is an easy to use flexible tuner
on board.
Please let there be one inside the kpa500 if it exists. Same thing for the
powersupply.

If not, sorry, no kpa500 for me.

Arie PA3A

-----Oorspronkelijk bericht-----

It weighs 10 kilos, does NOT have a built in tuner, but DOES have a
built-in linear power supply good for all common mains specs.

73, doug

______________________________________________________________
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

Doug Faunt N6TQS +1-510-655-8604

KPA500 active devices!!

In reply to this post by Ken Kopp-3

There are two VRF2933's in push-pull, so they're not 750 watts each,
but per pair. There are only three amps in existance, and no devices have
been destroyed (yet). Again, 500 watts is a very conservative rating.
It's been key-down for 10 minutes withy no problems.

73, doug
______________________________________________________________
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

S Sacco

Re: KPA500 active devices!!

The VRF2933 is rated "3:1 Load VSWR Capability at Specifi ed Operating
Conditions" according to its datasheet; perhaps that's why there no
built-in ATU.

On Sat, Apr 17, 2010 at 6:44 PM, Doug Faunt N6TQS +1-510-655-8604
<[hidden email]> wrote:

> There are two VRF2933's in push-pull, so they're not 750 watts each,
> but per pair. There are only three amps in existance, and no devices have
> been destroyed (yet). Again, 500 watts is a very conservative rating.
> It's been key-down for 10 minutes withy no problems.
>
> 73, doug
> ______________________________________________________________
> 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
>

Guy, K2AV

Re: KPA500 active devices!!

At any phase angle with no signal degradation. Minimum 20 dB gain,
300 watt output 400 typical per device. So being operated very
conservatively.

On Sat, Apr 17, 2010 at 7:22 PM, S Sacco <[hidden email]> wrote:

> The VRF2933 is rated "3:1 Load VSWR Capability at Specifi ed Operating
> Conditions" according to its datasheet; perhaps that's why there no
> built-in ATU.
>
>
>
> On Sat, Apr 17, 2010 at 6:44 PM, Doug Faunt N6TQS +1-510-655-8604
> <[hidden email]> wrote:
>> There are two VRF2933's in push-pull, so they're not 750 watts each,
>> but per pair. There are only three amps in existance, and no devices have
>> been destroyed (yet). Again, 500 watts is a very conservative rating.
>> It's been key-down for 10 minutes withy no problems.
>>
>> 73, doug
>> ______________________________________________________________
>> 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
>>
> ______________________________________________________________
> 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
>

Gary Gregory

Re: KPA500 active devices!!

Hi All'

Works for me..Bring it on Elecraft...!!!
Gary

On Sun, Apr 18, 2010 at 9:30 AM, Guy Olinger K2AV <[hidden email]>wrote:

> At any phase angle with no signal degradation. Minimum 20 dB gain,
> 300 watt output 400 typical per device. So being operated very
> conservatively.
>
> On Sat, Apr 17, 2010 at 7:22 PM, S Sacco <[hidden email]> wrote:
> > The VRF2933 is rated "3:1 Load VSWR Capability at Specifi ed Operating
> > Conditions" according to its datasheet; perhaps that's why there no
> > built-in ATU.
> >
> >
> >
> > On Sat, Apr 17, 2010 at 6:44 PM, Doug Faunt N6TQS +1-510-655-8604
> > <[hidden email]> wrote:
> >> There are two VRF2933's in push-pull, so they're not 750 watts each,
> >> but per pair. There are only three amps in existance, and no devices
> have
> >> been destroyed (yet). Again, 500 watts is a very conservative rating.
> >> It's been key-down for 10 minutes withy no problems.
> >>
> >> 73, doug
> >> ______________________________________________________________
> >> 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
> >>
> > ______________________________________________________________
> > 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
> >
> ______________________________________________________________
> 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
>

--
Gary
VK4FD - Motorhome Mobile
http://www.qsl.net/vk4fd/
K3 #679
For everything else there's Mastercard!!!
______________________________________________________________
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

alsopb

Re: KPA500 active devices!!

In reply to this post by Guy, K2AV

Just for curiosity, what do a pair of VRF2933 cost? Availability?

73 de Brian/K3KO

Guy Olinger K2AV wrote:

> At any phase angle with no signal degradation. Minimum 20 dB gain,
> 300 watt output 400 typical per device. So being operated very
> conservatively.
>
> On Sat, Apr 17, 2010 at 7:22 PM, S Sacco <[hidden email]> wrote:
>> The VRF2933 is rated "3:1 Load VSWR Capability at Specifi ed Operating
>> Conditions" according to its datasheet; perhaps that's why there no
>> built-in ATU.
>>
>>
>>
>> On Sat, Apr 17, 2010 at 6:44 PM, Doug Faunt N6TQS +1-510-655-8604
>> <[hidden email]> wrote:
>>> There are two VRF2933's in push-pull, so they're not 750 watts each,
>>> but per pair. There are only three amps in existance, and no devices have
>>> been destroyed (yet). Again, 500 watts is a very conservative rating.
>>> It's been key-down for 10 minutes withy no problems.
>>>
>>> 73, doug
>>> ______________________________________________________________
>>> 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
>>>
>> ______________________________________________________________
>> 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
>>
> ______________________________________________________________
> 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
>

Joe Subich, W4TV-4

Re: KPA500 active devices!!

In reply to this post by Doug Faunt N6TQS +1-510-655-8604

The VRF2933 is rated for 300 Watts each according to the data
sheet on the manufacturer's web site (Microsemi) ... That makes
their use in a 500 W amplifier reasonable from an IMD perspective.

The VRF 2933 minimum gain is also 20dB (23 dB typical) so it
would appear that the KPA-500 should be capable of clean
operation with 5 W of drive (e.g., K3 in low power mode).

73,

... Joe, W4TV

> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]] On Behalf Of Doug
> Faunt N6TQS +1-510-655-8604
> Sent: Saturday, April 17, 2010 6:45 PM
> To: [hidden email]
> Subject: [Elecraft] KPA500 active devices!!
>
>
> There are two VRF2933's in push-pull, so they're not 750
> watts each, but per pair. There are only three amps in
> existance, and no devices have been destroyed (yet). Again,
> 500 watts is a very conservative rating. It's been key-down
> for 10 minutes withy no problems.
>
> 73, doug

juergen piezo

Re: KPA500 active devices!!

Hi Joe

Have you seen any IMD data on these devices?

John

--- On Sat, 4/17/10, Joe Subich, W4TV <[hidden email]> wrote:

> From: Joe Subich, W4TV <[hidden email]>
> Subject: Re: [Elecraft] KPA500 active devices!!
> To: "'Doug Faunt N6TQS +1-510-655-8604'" <[hidden email]>, [hidden email]
> Date: Saturday, April 17, 2010, 4:45 PM
>
> The VRF2933 is rated for 300 Watts each according to the
> data
> sheet on the manufacturer's web site (Microsemi) ... That
> makes
> their use in a 500 W amplifier reasonable from an IMD
> perspective.
>
> The VRF 2933 minimum gain is also 20dB (23 dB typical) so
> it
> would appear that the KPA-500 should be capable of clean
> operation with 5 W of drive (e.g., K3 in low power mode).
>
> 73,
>
> ... Joe, W4TV
>
>
>
>
> > -----Original Message-----
> > From: [hidden email]
>
> > [mailto:[hidden email]]
> On Behalf Of Doug
> > Faunt N6TQS +1-510-655-8604
> > Sent: Saturday, April 17, 2010 6:45 PM
> > To: [hidden email]
> > Subject: [Elecraft] KPA500 active devices!!
> >
> >
> > There are two VRF2933's in push-pull, so they're not
> 750
> > watts each, but per pair. There are only three
> amps in
> > existance, and no devices have been destroyed
> (yet). Again,
> > 500 watts is a very conservative rating. It's been
> key-down
> > for 10 minutes withy no problems.
> >
> > 73, doug
>
>
> ______________________________________________________________
> 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
>

Dave KQ3T

Re: KPA500 active devices!!

In reply to this post by alsopb

Digi-Key has them listed at $153.34 each (Qty 1), down to $86.67 in lots
of 1000.

They have 30 in stock, if you want to order spares early :)

73
Dave KQ3T

Brian Alsop wrote:
> Just for curiosity, what do a pair of VRF2933 cost? Availability?
>
> 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

juergen piezo

Re: KPA500 active devices!!

In reply to this post by alsopb

Hi Brian

Digikey has them listed for about 154 dollars per piece.

The datasheet mentions superb IMD performance however there is no IMD data on the datasheet. I wonder if they perform as well as the MRF150's? in terms of IMD performance.

John

--- On Sat, 4/17/10, Brian Alsop <[hidden email]> wrote:

> From: Brian Alsop <[hidden email]>
> Subject: Re: [Elecraft] KPA500 active devices!!
> To:
> Cc: [hidden email]
> Date: Saturday, April 17, 2010, 4:42 PM
> Just for curiosity, what do a pair of
> VRF2933 cost? Availability?
>
> 73 de Brian/K3KO
>
> Guy Olinger K2AV wrote:
> > At any phase angle with no signal degradation.
> Minimum 20 dB gain,
> > 300 watt output 400 typical per device. So being
> operated very
> > conservatively.
> >
> > On Sat, Apr 17, 2010 at 7:22 PM, S Sacco <[hidden email]>
> wrote:
> >> The VRF2933 is rated "3:1 Load VSWR Capability at
> Specifi ed Operating
> >> Conditions" according to its datasheet; perhaps
> that's why there no
> >> built-in ATU.
> >>
> >>
> >>
> >> On Sat, Apr 17, 2010 at 6:44 PM, Doug Faunt N6TQS
> +1-510-655-8604
> >> <[hidden email]>
> wrote:
> >>> There are two VRF2933's in push-pull, so
> they're not 750 watts each,
> >>> but per pair. There are only three amps
> in existance, and no devices have
> >>> been destroyed (yet). Again, 500 watts
> is a very conservative rating.
> >>> It's been key-down for 10 minutes withy no
> problems.
> >>>
> >>> 73, doug
> >>>
> ______________________________________________________________
> >>> 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
> >>>
> >>
> ______________________________________________________________
> >> 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
> >>
> >
> ______________________________________________________________
> > 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
> >
>
> ______________________________________________________________
> 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
>

Dave-3

Re: KPA500 active devices!!

In reply to this post by Doug Faunt N6TQS +1-510-655-8604

digikey has them at $153.34 each

now the PA is out of the bag, perhaps we will see progress on the long
promised board to lock the radio to an external reference....the ext ref
socket on the k3 has been blanked off for a long time now!

Dave

ww2r

>
> Message: 49
> Date: Sat, 17 Apr 2010 23:42:39 +0000
> From: Brian Alsop <[hidden email]>
> Subject: Re: [Elecraft] KPA500 active devices!!
> Cc: [hidden email]
> Message-ID: <[hidden email]>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> Just for curiosity, what do a pair of VRF2933 cost? Availability?
>
> 73 de Brian/K3KO
>

Joe Subich, W4TV-4

Re: KPA500 active devices!!

In reply to this post by juergen piezo

John,

It's not shown on the datasheet. However, the VRF2933 is
specified as a communications product (not a repurposed
switching device) and is from the same family as the VRF150
(upgraded MRF150) which is specified at -32dBc (-38 dB to
ARRL standard). Since the VFR2933 is a higher gain part
(20 dB minimum gain) than the MRF150/VRF150, I would guess
the IMD performance might be a bit worse at maximum output.

Still, with the VRF2933 rated for 300W minimum - 375 typical
at 50V - the KPA-500 is not pushing them at 500W. I'd look
for IMD numbers on the mid to high 30's (ARRL spec).

73,

... Joe, W4TV

> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]] On Behalf Of juergen
> Sent: Saturday, April 17, 2010 7:50 PM
> To: [hidden email]
> Subject: Re: [Elecraft] KPA500 active devices!!
>
>
>
> Hi Joe
>
> Have you seen any IMD data on these devices?
>
>
> John
>
>
> --- On Sat, 4/17/10, Joe Subich, W4TV <[hidden email]> wrote:
>
> > From: Joe Subich, W4TV <[hidden email]>
> > Subject: Re: [Elecraft] KPA500 active devices!!
> > To: "'Doug Faunt N6TQS +1-510-655-8604'" <[hidden email]>,
> > [hidden email]
> > Date: Saturday, April 17, 2010, 4:45 PM
> >
> > The VRF2933 is rated for 300 Watts each according to the data
> > sheet on the manufacturer's web site (Microsemi) ... That
> > makes
> > their use in a 500 W amplifier reasonable from an IMD
> > perspective.
> >
> > The VRF 2933 minimum gain is also 20dB (23 dB typical) so it
> > would appear that the KPA-500 should be capable of clean
> > operation with 5 W of drive (e.g., K3 in low power mode).
> >
> > 73,
> >
> > ... Joe, W4TV
> >
> >
> >
> >
> > > -----Original Message-----
> > > From: [hidden email]
> >
> > > [mailto:[hidden email]]
> > On Behalf Of Doug
> > > Faunt N6TQS +1-510-655-8604
> > > Sent: Saturday, April 17, 2010 6:45 PM
> > > To: [hidden email]
> > > Subject: [Elecraft] KPA500 active devices!!
> > >
> > >
> > > There are two VRF2933's in push-pull, so they're not
> > 750
> > > watts each, but per pair. There are only three
> > amps in
> > > existance, and no devices have been destroyed
> > (yet). Again,
> > > 500 watts is a very conservative rating. It's been
> > key-down
> > > for 10 minutes withy no problems.
> > >
> > > 73, doug
> >
> >
> > ______________________________________________________________
> > 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
> >
>
>
>
> ______________________________________________________________
> 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

W8JI

Re: KPA500 active devices!!

In reply to this post by S Sacco

<
The VRF2933 is rated "3:1 Load VSWR Capability at Specifi ed
Operating
Conditions" according to its datasheet; perhaps that's why
there no
built-in ATU.>

.....but that doesn't mean SSB IMD would be acceptable, or
it would be safe in every circuit at that mismatch, so keep
that in mind. :-)

No matter what the data sheets say about device life, the PA
often needs to be kept within 1.5:1 or better SWR to meet
IMD specs. 3:1 is a huge loadline move, depending on the
direction of the impedance move it could really put the PA
into severe flattopping. Use a tuner or fix the antenna, be
safe.

73 Tom

On Sat, Apr 17, 2010 at 6:44 PM, Doug Faunt N6TQS
+1-510-655-8604
<[hidden email]> wrote:

> There are two VRF2933's in push-pull, so they're not 750
> watts each,
> but per pair. There are only three amps in existance, and
> no devices have
> been destroyed (yet). Again, 500 watts is a very
> conservative rating.
> It's been key-down for 10 minutes withy no problems.
>
> 73, doug
> ______________________________________________________________
> 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: A known bad url was replaced by VIPRE
> Please help support this email list: A known bad url was
> replaced by VIPRE
>

______________________________________________________________
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: A known bad url was replaced by VIPRE
Please help support this email list: A known bad url was
replaced by VIPRE

______________________________________________________________
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

Matt Palmer-4

Re: KPA500 active devices!!

Well said tom, an often overlooked aspect is the angle of the
mismatch, load pull is the only way to tell, while a 3:1 resitive is
not to harsh, very few things will survive a 3:1 at an inductive
reactance angle. Load pull is the only way to be sure, and I would be
uncomfortable making any claims until such a test has been done.

Matt
W8ESE
______________________________________________________________
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

Bob McGraw - K4TAX

Re: KPA500

In reply to this post by Don Wilhelm-4

Any switching supply today and one that's "worth it's salt" should operate
satisfactorily from 100 VAC to 250 VAC. So 120 VAC or 230VAC should not be
of conern.

73
Bob, K4TAX

----- Original Message -----
From: "Don Wilhelm" <[hidden email]>
To: "David Ferrington, M0XDF" <[hidden email]>
Cc: <[hidden email]>
Sent: Friday, April 16, 2010 3:40 PM
Subject: Re: [Elecraft] KPA500

> David,
>
> Because not all have hamshacks that are wired for 220 volts. If the
> space was not wired specifically for hamshack use, there is likely to be
> only 120 volt receptacles available. Up to 1000 watts draw (500 watts
> with 50% efficiency) on a normal 120 volt 15 amp circuit is practical,
> but attempting to run more than becomes marginal.
>
> 73,
> Don W3FPR
>
> David Ferrington, M0XDF wrote:
>> I'm intrigued, obviously we'd look for 220v over here, but why not 120v
>> in US?
>> 73 de M0XDF, K3 #174
>>
>>
> ______________________________________________________________
> 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
>

Guy, K2AV

Re: KPA500 active devices!!

In reply to this post by Matt Palmer-4

Device web site was claiming "any angle" in the device specs.
(!!!???) This should be fun to watch.

73, Guy.

On Sun, Apr 18, 2010 at 9:54 AM, Matt Palmer <[hidden email]> wrote:

> Well said tom, an often overlooked aspect is the angle of the
> mismatch, load pull is the only way to tell, while a 3:1 resitive is
> not to harsh, very few things will survive a 3:1 at an inductive
> reactance angle. Load pull is the only way to be sure, and I would be
> uncomfortable making any claims until such a test has been done.
>
>
> Matt
> W8ESE
> ______________________________________________________________
> 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
>

Doug Faunt N6TQS +1-510-655-8604

Re: KPA500

In reply to this post by Bob McGraw - K4TAX

It's not a switcher. As is common for linear power supplies (and not
uncommon for switchers), there's an input voltage selector as part of
the input power connector/fuse/switch combo.

Since the power transformer is 15 of the 22 pounds weight, one of my
thoughts was to ship that part (or an extra) ahead when traveling, and
when I asked was told that currently it takes about 15 minutes to
install, but that time might be cut.

73, doug

From: "Bob McGraw - K4TAX" <[hidden email]>
Date: Sun, 18 Apr 2010 16:24:43 -0500

Any switching supply today and one that's "worth it's salt" should operate
satisfactorily from 100 VAC to 250 VAC. So 120 VAC or 230VAC should not be
of conern.

73
Bob, K4TAX

----- Original Message -----
From: "Don Wilhelm" <[hidden email]>
To: "David Ferrington, M0XDF" <[hidden email]>
Cc: <[hidden email]>
Sent: Friday, April 16, 2010 3:40 PM
Subject: Re: [Elecraft] KPA500

> David,
>
> Because not all have hamshacks that are wired for 220 volts. If the
> space was not wired specifically for hamshack use, there is likely to be
> only 120 volt receptacles available. Up to 1000 watts draw (500 watts
> with 50% efficiency) on a normal 120 volt 15 amp circuit is practical,
> but attempting to run more than becomes marginal.
>
> 73,
> Don W3FPR
>
> David Ferrington, M0XDF wrote:
>> I'm intrigued, obviously we'd look for 220v over here, but why not 120v
>> in US?
>> 73 de M0XDF, K3 #174
______________________________________________________________
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

123