Elecraft › [QRO]

kpa 500

Classic

List

Threaded

12 messages Options

William H. Droeger, Jr.

kpa 500

Has anybody heard how much power out the k3/10 will drive the kpa500
amp to? As mostly a qrper it might be nice to have a lil juice once
in a while. I can get 12w max out of my k3/10 and was hoping since
the kpa500 is a solid state amp, I might get 400-500 watts out of it
with 12 watts of drive. Thanks-Skip KT9T
______________________________________________________________
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

Byron N6NUL

Re: kpa 500

Well, let's see if I can do this right: 15 db = 10 log (Pout / 12 watts)

where 15db is the FCC maximum allowed gain. Assuming that 12 watts
will drive the KPA500, we solve for Pout as: 12 watts * 10^1.5 = 379
watts

So, if I did the calculation correctly, that would be legal maximum. I
would suspect the gain to be less, perhaps in the 200-300 watt range
for no other reason than it feels right to my mind. There may also
have been an email from Lyle that mentioned something in the 200 watt
range, but I'm not sure.

73, Byron N6NUL

On Thu, Dec 16, 2010 at 4:11 PM, William H. Droeger, Jr.
<[hidden email]> wrote:
> Has anybody heard how much power out the k3/10 will drive the kpa500
> amp to? As mostly a qrper it might be nice to have a lil juice once
> in a while. I can get 12w max out of my k3/10 and was hoping since
> the kpa500 is a solid state amp, I might get 400-500 watts out of it
> with 12 watts of drive. Thanks-Skip KT9T

--
- Northern California Contest Club
- CU in the 2011 Cal QSO Party 1-2 Oct 2011
- www.cqp.org
______________________________________________________________
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: kpa 500

In reply to this post by William H. Droeger, Jr.

There is still an FCC limit of 15 db. Turning that around, the
smallest legal amount of drive to put out 500 watts would be 15.8
watts.

73, Guy.

On Thu, Dec 16, 2010 at 7:11 PM, William H. Droeger, Jr.
<[hidden email]> wrote:

> Has anybody heard how much power out the k3/10 will drive the kpa500
> amp to? As mostly a qrper it might be nice to have a lil juice once
> in a while. I can get 12w max out of my k3/10 and was hoping since
> the kpa500 is a solid state amp, I might get 400-500 watts out of it
> with 12 watts of drive. Thanks-Skip KT9T
> ______________________________________________________________
> 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

AC7AC

Re: kpa 500

In reply to this post by Byron N6NUL

CONTENTS DELETED

The author has deleted this message.

Bob Cunnings NW8L

Re: kpa 500

In reply to this post by William H. Droeger, Jr.

FWIW this was posted back in September:

http://www.mail-archive.com/elecraft@.../msg102741.html

"The KPA500 requires 30 to 40 watts for full output."

which puts gain at 12dB or so.

Bob NW8L

On Thu, Dec 16, 2010 at 5:11 PM, William H. Droeger, Jr.
<[hidden email]> wrote:

Doug Faunt N6TQS +1-510-655-8604

Re: kpa 500

In reply to this post by AC7AC

Is there any way making the 100watt PA kick in before 12 watts? My IC2KL
needs about 12W for 400W output, and I'd prefer to be using the KPA100 amp
at 12W then pushing the low power PA. OTOH, which would give the cleanest
signal at 12W, the low power or the high power PA?

73, doug

packing tomorrow to leave VK9NN

> And if you care about transmitting the cleanest signal, you'll hold the
> K3/10 output to 10 watts PEP. Squeezing higher power out degrades the IMD.
> The Power control provides some additional room to be sure everyone can
> make
> the rated 10 watts.
>
> The same is true for the K2/10.
>
> Ron AC7AC
>
> -----Original Message-----
> Well, let's see if I can do this right: 15 db = 10 log (Pout / 12 watts)
>
> where 15db is the FCC maximum allowed gain. Assuming that 12 watts
> will drive the KPA500, we solve for Pout as: 12 watts * 10^1.5 = 379
> watts
>
> So, if I did the calculation correctly, that would be legal maximum. I
> would suspect the gain to be less, perhaps in the 200-300 watt range
> for no other reason than it feels right to my mind. There may also
> have been an email from Lyle that mentioned something in the 200 watt
> range, but I'm not sure.
>
> 73, Byron N6NUL
>
>
> ______________________________________________________________
> 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
>

Jon Kåre Hellan

Re: kpa 500

In reply to this post by Guy, K2AV

On 12/17/2010 01:25 AM, Guy Olinger K2AV wrote:
> There is still an FCC limit of 15 db. Turning that around, the
> smallest legal amount of drive to put out 500 watts would be 15.8
> watts.
>

.. in the United States.

73
Jon LA4RT

> 73, Guy.
>
> On Thu, Dec 16, 2010 at 7:11 PM, William H. Droeger, Jr.
> <[hidden email]> wrote:
>> Has anybody heard how much power out the k3/10 will drive the kpa500
>> amp to? As mostly a qrper it might be nice to have a lil juice once
>> in a while. I can get 12w max out of my k3/10 and was hoping since
>> the kpa500 is a solid state amp, I might get 400-500 watts out of it
>> with 12 watts of drive. Thanks-Skip KT9T
>> ______________________________________________________________
>> 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

hf4me

Re: kpa 500

In reply to this post by AC7AC

"Squeezing higher power out degrades the IMD."

SO... The "10 watt" amp feeds the 100 w PA? Does it get fed with 10 watts
or 12 watts? What does that mean to the IMD of the 100 w PA by the cause of
the degraded IMD being fed into the PA?

73, de Jim KG0KP

----- Original Message -----
From: "Ron D'Eau Claire" <[hidden email]>
To: <[hidden email]>
Sent: Thursday, December 16, 2010 6:42 PM
Subject: Re: [Elecraft] kpa 500

Dave, G4AON

Re: kpa 500

In reply to this post by William H. Droeger, Jr.

From my measurements, the IMD of both the K3 100W PA and the 10W amp
improve by around 10 dB at 1/4 power. In my shack running the K3 at 20 ~
25 Watts works very well into an Acom 1000 linear for the UK power limit
of 400 Watts.

73 Dave, G4AON
K3/100 #80
--------------------------------
"Squeezing higher power out degrades the IMD."

SO... The "10 watt" amp feeds the 100 w PA? Does it get fed with 10 watts
or 12 watts? What does that mean to the IMD of the 100 w PA by the cause of
the degraded IMD being fed into the PA?

73, de Jim KG0KP
______________________________________________________________
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

AC7AC

Re: kpa 500

In reply to this post by hf4me

CONTENTS DELETED

The author has deleted this message.

AC7AC

Re: kpa 500

CONTENTS DELETED

The author has deleted this message.

Johnny Siu

kpa 500 + 6 metre pre amp

Hello Group,

K3's RX sensitivity in 6 metre is relatively low so that a PR6 is required.

Is it possible to put a RX pre-amp inside the KPA500 so as to streamline the
cabling among the options?

cheers,

Johnny VR2XMC

______________________________________________________________
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