[KPA500]And the question is ...
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Who is going to calculated alternate replacement values of the resistors in the two attenuators so that the KPA500 may be driven to a full 500 watts by a K3 / 10?
Mark, NØOKS ______________________________________________________________ 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 |
Re: [KPA500]And the question is ...
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Mark wrote:
> Who is going to calculated alternate replacement values of the resistors in the two attenuators so that the KPA500 may be driven to a > > full 500 watts by a K3 / 10? > Mark, NØOKS You are, if you intend to try this on your new KPA-500. -Bruce, N1RX ______________________________________________________________ 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 |
Re: [KPA500]And the question is ...
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I'll do it!
Just send me a KPA500 and I am good to go! Phil Santa Fe On Mar 15, 2011, at 3:16 PM, Bruce Beford wrote: > Mark wrote: > >> Who is going to calculated alternate replacement values of the resistors > in the two attenuators so that the KPA500 may be driven to a > > full 500 > watts by a K3 / 10? >> Mark, NØOKS > > You are, if you intend to try this on your new KPA-500. -Bruce, N1RX > > > > ______________________________________________________________ > 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 |
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In reply to this post by N0OKS
OK, so far I get the first pad to have a characteristic impedance of 70 ohms and an attenuation of 2.5 dB. I need help on the second one as it is an impedance converter also.
Mark, NØOKS ______________________________________________________________ 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 |
Re: [KPA500]And the question is ...
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In reply to this post by Phillip Lontz
A European model will be required: we don't have the gain restriction you
have, however, we do like stability and putting lots of gain into one box could be tricky. David G3UNA ----- Original Message ----- From: "Phil Townsend" <[hidden email]> To: "Bruce Beford" <[hidden email]> Cc: <[hidden email]> Sent: Tuesday, March 15, 2011 9:31 PM Subject: Re: [Elecraft] [KPA500]And the question is ... I'll do it! Just send me a KPA500 and I am good to go! Phil Santa Fe On Mar 15, 2011, at 3:16 PM, Bruce Beford wrote: > Mark wrote: > >> Who is going to calculated alternate replacement values of the resistors > in the two attenuators so that the KPA500 may be driven to a > > full 500 > watts by a K3 / 10? >> Mark, NØOKS > > You are, if you intend to try this on your new KPA-500. -Bruce, N1RX > > 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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On 3/16/2011 11:02 AM, David Cutter wrote:
> A European model will be required: It might be NICE to be able to drive it at lower power, but I don't understand why it is REQUIRED. It would be NICE to be able to drive it to rated power from a barefoot K3/10 (or K2/10), but that could push the driver to the point where it produces a bit more IM and THD (that is, splatter and harmonics). That's the main reason that firmware for the K3/100 now limits output power to 110 watts. > we don't have the gain restriction you have, however, we do like stability and putting lots of gain into one box could be tricky. The Elecraft design engineers are quite sharp, and have carefully thought quite things like this. As a result of my own EE background and ongoing conversations with one of them who is a neighbor (and a serious contester), I'm firmly convinced that they have made a very intelligent set of design decisions about these issues. The last thing our ham bands need is more loud lids spewing trash. 73, Jim K9YC ______________________________________________________________ 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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Well, it's NICE that you can see the tongue firmly in my cheek, Jim. I
presume the others on this thread are thinking the same way. 73 David G3UNA > On 3/16/2011 11:02 AM, David Cutter wrote: >> A European model will be required: > > It might be NICE to be able to drive it at lower power, but I don't > understand why it is REQUIRED. It would be NICE to be able to drive it > to rated power from a barefoot K3/10 (or K2/10), but that could push the > driver to the point where it produces a bit more IM and THD (that is, > splatter and harmonics). That's the main reason that firmware for the > K3/100 now limits output power to 110 watts. > >> we don't have the gain restriction you have, however, we do like >> stability and putting lots of gain into one box could be tricky. > > The Elecraft design engineers are quite sharp, and have carefully > thought quite things like this. As a result of my own EE background and > ongoing conversations with one of them who is a neighbor (and a serious > contester), I'm firmly convinced that they have made a very intelligent > set of design decisions about these issues. The last thing our ham bands > need is more loud lids spewing trash. > > 73, Jim K9YC > 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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The question is: Is it feasible to improve the KPA500 to full output
with k3/10. Why should someone in Europe invest into the 100W PA if it is possible? 73, István Szabó On 3/16/2011 8:03 PM, David Cutter wrote: > Well, it's NICE that you can see the tongue firmly in my cheek, Jim. I > presume the others on this thread are thinking the same way. > > 73 > > David > G3UNA > > >> On 3/16/2011 11:02 AM, David Cutter wrote: >>> A European model will be required: >> It might be NICE to be able to drive it at lower power, but I don't >> understand why it is REQUIRED. It would be NICE to be able to drive it >> to rated power from a barefoot K3/10 (or K2/10), but that could push the >> driver to the point where it produces a bit more IM and THD (that is, >> splatter and harmonics). That's the main reason that firmware for the >> K3/100 now limits output power to 110 watts. >> >>> we don't have the gain restriction you have, however, we do like >>> stability and putting lots of gain into one box could be tricky. >> The Elecraft design engineers are quite sharp, and have carefully >> thought quite things like this. As a result of my own EE background and >> ongoing conversations with one of them who is a neighbor (and a serious >> contester), I'm firmly convinced that they have made a very intelligent >> set of design decisions about these issues. The last thing our ham bands >> need is more loud lids spewing trash. >> >> 73, Jim K9YC >> > ______________________________________________________________ > 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 |
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For portable use without mains power - 100W on batteries works fine.
73 de M0XDF, K3 #174, P3 #108 -- Sometimes I wonder whether the world is being run by smart people who are putting us on or by imbeciles who really mean it. -Mark Twain, author and humorist (1835-1910) On 16 Mar 2011, at 20:17, István Szabó wrote: > The question is: Is it feasible to improve the KPA500 to full output > with k3/10. Why should someone in Europe invest into the 100W PA if it > is possible? ______________________________________________________________ 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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In reply to this post by ha4zd
On 3/16/2011 1:17 PM, István Szabó wrote:
> Is it feasible to improve the KPA500 to full output > with k3/10. Why should someone in Europe invest into the 100W PA if it > is possible? Please go back and read what I wrote. 73, Jim K9YC ______________________________________________________________ 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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In reply to this post by David Cutter
Regardless of FCC requirements, it is not feasible or desirable to
modify the KPA500 for lower power drive with a 10W exciter. Any modification of the input network to the KPA500 will seriously degrade the input SWR to the amplifier and also will put the KPA500 transistors at a strong risk of destruction from accidental over drive. Our protection circuitry and firmware are tightly integrated to provide a very reliable bullet-proof design. 73, Eric WA6HHQ ______________________________________________________________ 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 |
Re: [KPA500]And the question is ...
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In reply to this post by David Cutter
Agreed.
73, Eric On 3/16/2011 11:02 AM, David Cutter wrote: > we don't have the gain restriction you > have, however, we do like stability and putting lots of gain into one box > could be tricky. > > David > G3UNA ______________________________________________________________ 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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In reply to this post by Jim Brown-10
Agreed and the sale of KPA3 and KPA100 will be maintained as well.
On the other hand, I would like to have stainless steel screws in KPA500 as a standard provision. Summer in Hong Kong is very humid. I have already changed all the screws in my K3 with SS so as to avoid rusting. cheers, Johnny VR2XMC ________________________________ 寄件人﹕ Jim Brown <[hidden email]> 收件人﹕ [hidden email] 傳送日期﹕ 2011/3/17 (四) 2:58:08 AM 主題： [Elecraft] KPA500 Power Gain On 3/16/2011 11:02 AM, David Cutter wrote: > A European model will be required: It might be NICE to be able to drive it at lower power, but I don't understand why it is REQUIRED. It would be NICE to be able to drive it to rated power from a barefoot K3/10 (or K2/10), but that could push the driver to the point where it produces a bit more IM and THD (that is, splatter and harmonics). That's the main reason that firmware for the K3/100 now limits output power to 110 watts. > we don't have the gain restriction you have, however, we do like stability and >putting lots of gain into one box could be tricky. The Elecraft design engineers are quite sharp, and have carefully thought quite things like this. As a result of my own EE background and ongoing conversations with one of them who is a neighbor (and a serious contester), I'm firmly convinced that they have made a very intelligent set of design decisions about these issues. The last thing our ham bands need is more loud lids spewing trash. 73, Jim K9YC ______________________________________________________________ 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 |
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In reply to this post by Jim Brown-10
As a Contester, can I add my unadulterated AMEN to this
post? I have a great receiver with my K3, but when on SSB, I am always at the mercy of everybody else's IMD products which no amount of filtering can completely get rid of. "Pointers high bouncing clean signals make not" Yankee Zero Delta Alpha, the DX Jedi :) -lu-W4LT- K3 # 3192 >The last thing our ham bands >need is more loud lids spewing trash. ______________________________________________________________ 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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