Re: [Elecraft] [ELECRAFT] KPA500 NEW OWNER QUESTIONS.......
In this discussion about ALC, I have to inject a bit of fact. The Elecraft transceivers K2/K3/K3S/KX2/KX3 use a power control system that is different from all other amateur transceivers, and unless there is a problem with the transceiver, there is no power overshoot. In fact, after a band change or a power setting change, the RF starts at a low level and builds up to the power knob setting after a dit time or a few syllables on voice. That means amplifier ALC is not necessary, and if used should never be used for power level control (doing that will cause distortion). W8JI - Tom Rauch is responding to operation with most transceivers driving the amplifier. With the Elecraft transceivers, the amplifier's ALC indicator should never come on unless there is an amplifier fault condition - high SWR, no antenna, etc. Tom W8JI should know - he designed several of the Ameritron amplifiers. Operated properly, there is no need for ALC at all, especially with those amplifiers employing cathode or grid detection of overload. For the amplifiers with more sophisticated fault detection, connecting the ALC line to the driving transceiver is OK because it allows the amplifier to shut down (or reduce power) the transceiver if a fault is detected. As Tom pointed out in at the end of his article, ALC should not be used as a power control mechanism - doing so will only lead to distortion. 73, Don W3FPR On 2/28/2019 10:19 PM, Bob McGraw K4TAX wrote: This fellow seems to have a good handle on the ALC issue as it relates to overshoot in the transceiver. https://www.w8ji.com/alc_exciter_power_overshoot.htm Here Tom goes into the discussion of good ALC vs. bad ALC systems. https://www.w8ji.com/ameritron_alc_adjustment.htm __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] [ELECRAFT] KPA500 NEW OWNER QUESTIONS.......
You can pull them via the KPA500 utility; Configuration Tab, Fault table. Rick nhc On 2/28/2019 9:08 PM, Dave Cole (NK7Z) wrote: Logs? Can you expand on that a bit? Does the KPA500 keep logs? How are they available please? 73s and thanks, Dave (NK7Z) https://www.nk7z.net Award Manager, 30MDG Grid Awards ARRL Technical Specialist ARRL Volunteer Examiner ARRL OOC for Oregon On 2/28/19 1:35 PM, Kevin der Kinderen wrote: It appears, after reviewing the logs, I hit it with 75 watts and probably blew one of the diodes in the front end. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net 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:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] [ELECRAFT] KPA500 NEW OWNER QUESTIONS.......
Thanks for that. I never understood the Ameritron ALC instruction for my ALS-600 so I just never used the ALC. That attached instruction was much clearer and made sense. Brian Denley KB1VBF Sent from my iPad > On Feb 28, 2019, at 10:19 PM, Bob McGraw K4TAX wrote: > > This fellow seems to have a good handle on the ALC issue as it relates to > overshoot in the transceiver. > > https://www.w8ji.com/alc_exciter_power_overshoot.htm > > > Here Tom goes into the discussion of good ALC vs. bad ALC systems. > > https://www.w8ji.com/ameritron_alc_adjustment.htm > > > 73 > Bob, K4TAX > > > >> On 2/28/2019 8:51 PM, K9MA wrote: >> Many years ago, I built a tube amplifier with what I thought was a fairly >> sophisticated ALC circuit. I could never get the ALC loop to be stable. I >> know a lot more about control systems now, but I still don't know how to get >> ALC around an amplifier to work, and apparently neither does anyone else. >> What I don't understand is why it's so hard with an external amplifier, as >> every transmitter has ALC for its internal 100 W amplifier, and that works >> fine. Why the same design doesn't work with an external amplifier is the >> mystery. >> >> The problem with just limiting the drive power and using the transmitter's >> ALC is that, especially for solid state amplifiers, the required drive power >> can vary considerably with SWR and temperature. That requires either riding >> the power control continuously or running your amplifier well below rated >> output most of the time. (Unless, of course, you're running a 2.5 kW >> amplifier, but that kind of margin is expensive.) So, if anyone could figure >> out how to get ALC to really work with an amplifier, I think that would be >> worth paying extra for. >> >> 73, >> Scott K9MA >> > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > 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:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] [ELECRAFT] KPA500 NEW OWNER QUESTIONS.......
Logs? Can you expand on that a bit? Does the KPA500 keep logs? How are they available please? 73s and thanks, Dave (NK7Z) https://www.nk7z.net Award Manager, 30MDG Grid Awards ARRL Technical Specialist ARRL Volunteer Examiner ARRL OOC for Oregon On 2/28/19 1:35 PM, Kevin der Kinderen wrote: It appears, after reviewing the logs, I hit it with 75 watts and probably blew one of the diodes in the front end. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] [ELECRAFT] KPA500 NEW OWNER QUESTIONS.......
This fellow seems to have a good handle on the ALC issue as it relates to overshoot in the transceiver. https://www.w8ji.com/alc_exciter_power_overshoot.htm Here Tom goes into the discussion of good ALC vs. bad ALC systems. https://www.w8ji.com/ameritron_alc_adjustment.htm 73 Bob, K4TAX On 2/28/2019 8:51 PM, K9MA wrote: Many years ago, I built a tube amplifier with what I thought was a fairly sophisticated ALC circuit. I could never get the ALC loop to be stable. I know a lot more about control systems now, but I still don't know how to get ALC around an amplifier to work, and apparently neither does anyone else. What I don't understand is why it's so hard with an external amplifier, as every transmitter has ALC for its internal 100 W amplifier, and that works fine. Why the same design doesn't work with an external amplifier is the mystery. The problem with just limiting the drive power and using the transmitter's ALC is that, especially for solid state amplifiers, the required drive power can vary considerably with SWR and temperature. That requires either riding the power control continuously or running your amplifier well below rated output most of the time. (Unless, of course, you're running a 2.5 kW amplifier, but that kind of margin is expensive.) So, if anyone could figure out how to get ALC to really work with an amplifier, I think that would be worth paying extra for. 73, Scott K9MA __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] [ELECRAFT] KPA500 NEW OWNER QUESTIONS.......
Many years ago, I built a tube amplifier with what I thought was a fairly sophisticated ALC circuit. I could never get the ALC loop to be stable. I know a lot more about control systems now, but I still don't know how to get ALC around an amplifier to work, and apparently neither does anyone else. What I don't understand is why it's so hard with an external amplifier, as every transmitter has ALC for its internal 100 W amplifier, and that works fine. Why the same design doesn't work with an external amplifier is the mystery. The problem with just limiting the drive power and using the transmitter's ALC is that, especially for solid state amplifiers, the required drive power can vary considerably with SWR and temperature. That requires either riding the power control continuously or running your amplifier well below rated output most of the time. (Unless, of course, you're running a 2.5 kW amplifier, but that kind of margin is expensive.) So, if anyone could figure out how to get ALC to really work with an amplifier, I think that would be worth paying extra for. 73, Scott K9MA On 2/28/2019 13:12, Bob McGraw K4TAX wrote: Yes, improperly or incorrectly using ALC with any amp or any transceiver, for that matter, can and usually does produce distortion and splatter. Just look at some of the signals on the bands and observe the ALC overshoot which exists with many radios. And it is made worse by the addition of an amplifier in line. It isn't pretty!. Yet it has little impact on the on frequency signal as heard and thus the "great signal" complements follow. But look at the other factors where you will find "NOT so great signal". These points should be addressed as well. 73 Bob, K4TAX On 2/28/2019 1:04 PM, j...@kk9a.com wrote: I have not used ALC with any amplifier since transceivers switched to transistor finals. From what I have read on this list, using ALC improperly can cause distortion. Just be very careful with your drive level. I believe that the KPA500 can handle 100 watts in bypass, 200 watts may be pushing it. The KPA500 is a very nice amp and it is easy to use with any transceiver. GL, John KK9A JIM LAGESON N0UR wrote _Thu Feb 28 13:07:27 EST 2019_ - I have never owned an amp before and recently put together a KPA500. All seems to be working well, but I have a few questions. I am using with a IC-7300. How important is the ALC cable? I notice it is not included in the Basic Cabling Diagram in the manual but is discussed later in the manual. If I were accidently to run 100 watts into the KPA500 will the PWRIN HI Hard Fault/STBY protect itself before any damage is done. Would ALC protect me from that? Is it standard procedure to keep the KPA500 in line when turned off and not in use? I see you may run up to 200 through the KPA500 in STBY. Is there any concerns or settings on radio when running full break in on CW? Thanks Jim-N0UR ml -- Scott K9MA k...@sdellington.us __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
[Elecraft] KPA500 new owner questions......
The report that a KPA500 was damaged by 100 W drive had me coding a new enhancement to my Kenwood/Elecraft control interface the same day. I now continuously monitor the TS-590 power setting and, if it exceeds 35 W, I assert the KAT500 key line inhibit. The key line stays inhibited until the TS-590 power setting goes below 31 W. The diagnostic output of the interface shows what happens (PC; is the TS-590 power set/read command). New PC - PC032; New PC - PC033; New PC - PC034; New PC - PC035; Power protection activated Sending AMPI1; to KAT500 New AMPI - AMPI1; New PC - PC036; New PC - PC034; New PC - PC032; New PC - PC031; New PC - PC030; Power protection cleared Sending AMPI0; to KAT500 New AMPI - AMPI0; New PC - PC029; New PC - PC028; 73, Andy, k3wyc __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] [ELECRAFT] KPA500 NEW OWNER QUESTIONS.......
And now the voice of caution. I think the KPA500 with the KAT500 and my Flex are a wonderful combination. That said, my KPA500 stopped working. It appears, after reviewing the logs, I hit it with 75 watts and probably blew one of the diodes in the front end. I can dig up the explanation if needed. It may have been a case where it took me a while to realize what I was doing. In fact, I can't remember the event other than it was logged by the KPA500. By the way... just having that log available is valuable. I now have the Flex set to 25 watts max out. 73, Kev K4VD On Thu, Feb 28, 2019 at 4:22 PM Barry Simpson wrote: > I have had my KPA500 for around 5 years. I frequently feed through 200w > from my TS990S. > > I have also accidentally abused it many times by putting 100w or more into > it or using the wrong antenna or some such operator error. > > It has always just faulted appropriately and come back up smiling. > > It is a tough little cookie ! > > Barry VK2BJ > > Sent from my iPad > > > On 1 Mar 2019, at 06:12, Bob McGraw K4TAX wrote: > > > > Yes, improperly or incorrectly using ALC with any amp or any > transceiver, for that matter, can and usually does produce distortion and > splatter. Just look at some of the signals on the bands and observe the > ALC overshoot which exists with many radios. And it is made worse by the > addition of an amplifier in line. It isn't pretty!. Yet it has little > impact on the on frequency signal as heard and thus the "great signal" > complements follow. But look at the other factors where you will find "NOT > so great signal". These points should be addressed as well. > > > > 73 > > > > Bob, K4TAX > > > > > >> On 2/28/2019 1:04 PM, j...@kk9a.com wrote: > >> I have not used ALC with any amplifier since transceivers switched to > transistor finals. From what I have read on this list, using ALC improperly > can cause distortion. Just be very careful with your drive level. I > believe that the KPA500 can handle 100 watts in bypass, 200 watts may be > pushing it. The KPA500 is a very nice amp and it is easy to use with any > transceiver. > >> > >> GL, > >> John KK9A > >> > >> > >> JIM LAGESON N0UR wrote > >> _Thu Feb 28 13:07:27 EST 2019_ > >> > >> > >> - > >> > >> I have never owned an amp before and recently put together a KPA500. All > >> seems to be working well, but I have a few questions. I am using with a > >> IC-7300. > >> > >> How important is the ALC cable? I notice it is not included in the Basic > >> Cabling Diagram in the manual but is discussed later in the manual. > >> > >> If I were accidently to run 100 watts into the KPA500 will the PWRIN HI > >> Hard Fault/STBY protect itself before any damage is done. Would ALC > protect > >> me from that? > >> > >> Is it standard procedure to keep the KPA500 in line when turned off and > not > >> in use? I see you may run up to 200 through the KPA500 in STBY. > >> > >> Is there any concerns or settings on radio when running full break in > on CW? > >> > >> Thanks > >> Jim-N0UR > >> __ > >> Elecraft mailing list > >> Home: http://mailman.qth.net/mailman/listinfo/elecraft > >> Help: http://mailman.qth.net/mmfaq.htm > >> Post: mailto:Elecraft@mailman.qth.net > >> > >> 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:Elecraft@mailman.qth.net > > > > 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:Elecraft@mailman.qth.net > > 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:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] [ELECRAFT] KPA500 NEW OWNER QUESTIONS.......
I have had my KPA500 for around 5 years. I frequently feed through 200w from my TS990S. I have also accidentally abused it many times by putting 100w or more into it or using the wrong antenna or some such operator error. It has always just faulted appropriately and come back up smiling. It is a tough little cookie ! Barry VK2BJ Sent from my iPad > On 1 Mar 2019, at 06:12, Bob McGraw K4TAX wrote: > > Yes, improperly or incorrectly using ALC with any amp or any transceiver, for > that matter, can and usually does produce distortion and splatter. Just > look at some of the signals on the bands and observe the ALC overshoot which > exists with many radios. And it is made worse by the addition of an > amplifier in line. It isn't pretty!. Yet it has little impact on the on > frequency signal as heard and thus the "great signal" complements follow. But > look at the other factors where you will find "NOT so great signal". These > points should be addressed as well. > > 73 > > Bob, K4TAX > > >> On 2/28/2019 1:04 PM, j...@kk9a.com wrote: >> I have not used ALC with any amplifier since transceivers switched to >> transistor finals. From what I have read on this list, using ALC improperly >> can cause distortion. Just be very careful with your drive level. I believe >> that the KPA500 can handle 100 watts in bypass, 200 watts may be pushing it. >> The KPA500 is a very nice amp and it is easy to use with any transceiver. >> >> GL, >> John KK9A >> >> >> JIM LAGESON N0UR wrote >> _Thu Feb 28 13:07:27 EST 2019_ >> >> >> - >> >> I have never owned an amp before and recently put together a KPA500. All >> seems to be working well, but I have a few questions. I am using with a >> IC-7300. >> >> How important is the ALC cable? I notice it is not included in the Basic >> Cabling Diagram in the manual but is discussed later in the manual. >> >> If I were accidently to run 100 watts into the KPA500 will the PWRIN HI >> Hard Fault/STBY protect itself before any damage is done. Would ALC protect >> me from that? >> >> Is it standard procedure to keep the KPA500 in line when turned off and not >> in use? I see you may run up to 200 through the KPA500 in STBY. >> >> Is there any concerns or settings on radio when running full break in on CW? >> >> Thanks >> Jim-N0UR >> __ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:Elecraft@mailman.qth.net >> >> 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:Elecraft@mailman.qth.net > > 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:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] [ELECRAFT] KPA500 NEW OWNER QUESTIONS.......
Yes, improperly or incorrectly using ALC with any amp or any transceiver, for that matter, can and usually does produce distortion and splatter. Just look at some of the signals on the bands and observe the ALC overshoot which exists with many radios. And it is made worse by the addition of an amplifier in line. It isn't pretty!. Yet it has little impact on the on frequency signal as heard and thus the "great signal" complements follow. But look at the other factors where you will find "NOT so great signal". These points should be addressed as well. 73 Bob, K4TAX On 2/28/2019 1:04 PM, j...@kk9a.com wrote: I have not used ALC with any amplifier since transceivers switched to transistor finals. From what I have read on this list, using ALC improperly can cause distortion. Just be very careful with your drive level. I believe that the KPA500 can handle 100 watts in bypass, 200 watts may be pushing it. The KPA500 is a very nice amp and it is easy to use with any transceiver. GL, John KK9A JIM LAGESON N0UR wrote _Thu Feb 28 13:07:27 EST 2019_ - I have never owned an amp before and recently put together a KPA500. All seems to be working well, but I have a few questions. I am using with a IC-7300. How important is the ALC cable? I notice it is not included in the Basic Cabling Diagram in the manual but is discussed later in the manual. If I were accidently to run 100 watts into the KPA500 will the PWRIN HI Hard Fault/STBY protect itself before any damage is done. Would ALC protect me from that? Is it standard procedure to keep the KPA500 in line when turned off and not in use? I see you may run up to 200 through the KPA500 in STBY. Is there any concerns or settings on radio when running full break in on CW? Thanks Jim-N0UR __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net 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:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] [ELECRAFT] KPA500 NEW OWNER QUESTIONS.......
On 2/28/2019 11:04 AM, j...@kk9a.com wrote: I have not used ALC with any amplifier since transceivers switched to transistor finals. From what I have read on this list, using ALC improperly can cause distortion. That's correct. And it's not limited to solid state amplifiers. The owner's manual for my Ten Tec Titan 425 amp, designed around 1979 and using a pair of 3CX800A7s, provides an ALC input, but advises against using ALC to set power. 73, Jim K9YC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
[Elecraft] [ELECRAFT] KPA500 NEW OWNER QUESTIONS.......
I have not used ALC with any amplifier since transceivers switched to transistor finals. From what I have read on this list, using ALC improperly can cause distortion. Just be very careful with your drive level. I believe that the KPA500 can handle 100 watts in bypass, 200 watts may be pushing it. The KPA500 is a very nice amp and it is easy to use with any transceiver. GL, John KK9A JIM LAGESON N0UR wrote _Thu Feb 28 13:07:27 EST 2019_ - I have never owned an amp before and recently put together a KPA500. All seems to be working well, but I have a few questions. I am using with a IC-7300. How important is the ALC cable? I notice it is not included in the Basic Cabling Diagram in the manual but is discussed later in the manual. If I were accidently to run 100 watts into the KPA500 will the PWRIN HI Hard Fault/STBY protect itself before any damage is done. Would ALC protect me from that? Is it standard procedure to keep the KPA500 in line when turned off and not in use? I see you may run up to 200 through the KPA500 in STBY. Is there any concerns or settings on radio when running full break in on CW? Thanks Jim-N0UR __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] KPA500 new owner questions.......
I agree with Rick just keep the drive power to the minimum needed to get the 500 watts out. Over driving will do nothing but distort the signal and most likely eventually damage the amp. I use 18 to 20 watts to get 500 out on 160 mtrs and a bit more to get same results on the higher bands. Bruce WW8II On Thu, Feb 28, 2019 at 1:08 PM Jim Lageson wrote: > I have never owned an amp before and recently put together a KPA500. All > seems to be working well, but I have a few questions. I am using with a > IC-7300. > > How important is the ALC cable? I notice it is not included in the Basic > Cabling Diagram in the manual but is discussed later in the manual. > > If I were accidently to run 100 watts into the KPA500 will the PWRIN HI > Hard Fault/STBY protect itself before any damage is done. Would ALC protect > me from that? > > Is it standard procedure to keep the KPA500 in line when turned off and not > in use? I see you may run up to 200 through the KPA500 in STBY. > > Is there any concerns or settings on radio when running full break in on > CW? > > Thanks > Jim-N0UR > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > 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:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] KPA500 new owner questions.......
When I read in the manual where it says "never exceed 40 watts" that leads me to believe one should not do that. While the protection circuit is fast and there is a 3 dB attenuator that switches in automatically, from 100 watts down 3 dB is still over 40 watts. I think I read here where someone hit the amp with 100 to 200 watts and now it needs repair. In other words, "they let the smoke out of the box". As to ALC, that is in my opinion and option and does not require the company to supply a cable or diagram. After all, what connector type for "other radio" is required? And in many cases, mine for one of my radios, there is NO ALC input. Thus I must BE VERY CAREFUL when I use that radio with my KPA500. As to using ALC, since your IC-7300 does have provision for external ALC, my suggestion is USE IT!. Page 17 in the manual "Using ALC" is quite clear about this. And for what it's worth, with my K3S, I do have the ALC interfaced from the amp to the radio. Just in case something goes amiss. With my radio that does not have ALC input, I must be careful to set the power correctly and then CHECK and RECHECK to see all is done correctly before transmitting. My KPA500 is in line in all station configurations and operation. Two transceivers, 160M - 6M. I find no need to physically or externally switch it out of line. 73 Bob, K4TAX On 2/28/2019 12:07 PM, Jim Lageson wrote: I have never owned an amp before and recently put together a KPA500. All seems to be working well, but I have a few questions. I am using with a IC-7300. How important is the ALC cable? I notice it is not included in the Basic Cabling Diagram in the manual but is discussed later in the manual. If I were accidently to run 100 watts into the KPA500 will the PWRIN HI Hard Fault/STBY protect itself before any damage is done. Would ALC protect me from that? Is it standard procedure to keep the KPA500 in line when turned off and not in use? I see you may run up to 200 through the KPA500 in STBY. Is there any concerns or settings on radio when running full break in on CW? Thanks Jim-N0UR __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net 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:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] KPA500 new owner questions.......
The fault ability of the KPA500 is fast, BUT I would not test that with 100 watts. The tuned input can only take so much abuse. ALC should be used as a secondary (emergency) limiter, not for everyday use. It will cause distortion (in part from overdriving the amp). Proper management of the input (power out, proper compression levels etc) is THE best way to manage the combination. Rick NHC On 2/28/2019 10:07 AM, Jim Lageson wrote: I have never owned an amp before and recently put together a KPA500. All seems to be working well, but I have a few questions. I am using with a IC-7300. How important is the ALC cable? I notice it is not included in the Basic Cabling Diagram in the manual but is discussed later in the manual. If I were accidently to run 100 watts into the KPA500 will the PWRIN HI Hard Fault/STBY protect itself before any damage is done. Would ALC protect me from that? Is it standard procedure to keep the KPA500 in line when turned off and not in use? I see you may run up to 200 through the KPA500 in STBY. Is there any concerns or settings on radio when running full break in on CW? Thanks Jim-N0UR __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net 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:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
[Elecraft] KPA500 new owner questions.......
I have never owned an amp before and recently put together a KPA500. All seems to be working well, but I have a few questions. I am using with a IC-7300. How important is the ALC cable? I notice it is not included in the Basic Cabling Diagram in the manual but is discussed later in the manual. If I were accidently to run 100 watts into the KPA500 will the PWRIN HI Hard Fault/STBY protect itself before any damage is done. Would ALC protect me from that? Is it standard procedure to keep the KPA500 in line when turned off and not in use? I see you may run up to 200 through the KPA500 in STBY. Is there any concerns or settings on radio when running full break in on CW? Thanks Jim-N0UR __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
