Re: [Elecraft] Amp specs
In addition, according to the user's manual, the key down time in CW at max power is ten minutes. I wouldn't want to do that to any of my VHF or UHF bricks, so it seems to me it's a pretty rugged amp. 73, Tom Amateur Radio Operator N5GE On Thu, 26 May 2011 08:09:25 -0700, Robert Friess wrote: >The KPA500 is rated for 500W PEP or CW. > >Bob, N6CM > [snip] __ 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] Amp specs
While it may be capable of hitting 750 watts key down ( and more) isn't it likely that CW is derated due to duty cycle issues? Probably power supply. Even if THP is conservative in ratings, there's probably a rational reason behind the spec as stated. Sent from my iPhone On May 26, 2011, at 10:22 AM, w...@w5ov.com wrote: > Well, no. > > THP's specs are all confusing because they are very cautious to not > . > > That said, the 1.2KFX is fully capable of 750w key down output. On CW, > PEP=AVG. > > __ 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] Amp specs
> could it be that 750 watts PEP is the same as 600 watts key down After spending a lot of time looking at solid state amplifier design the most likely reason for a 750 W PEP/600 W CW specification is either cooling or power supply limitations. In practice, if the power supply and cooling can support it, the CW rating could actually be 1 dB or so higher than the PEP rating simply since increased IMD is not a concern for CW/RTTY (single tone applications). One would normally set the PEP rating below the 1 dB compression point for maximum linearity (e.g. AB1 in tube parlance) while setting the CW rating somewhat higher (e.g., class B or even class C in the tube world). 73, ... Joe, W4TV On 5/26/2011 11:07 AM, riese-k3...@juno.com wrote: > could it be that 750 watts PEP is the same as 600 watts key down > > H > > Bob K3DJC > On Thu, 26 May 2011 06:50:48 -0500 "John Harper" writes: >> In looking at several HF amps, I notice that PEP and CW are usually >> of different levels for a given amp. >> >> For example, THP's HL-1.2 is rated at 750w PEP, 600w CW. Granted, a >> receiving station would not notice any difference in a 0.9 dB >> increase of power on any mode but I'm wondering how the KPA500 >> compares - is the 500w rating PEP or CW? >> >> John AE5X >> Radio: 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:Elecraft@mailman.qth.net >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> >> > > > Groupon™ Official Site > 1 ridiculously huge coupon a day. Get 50-90% off your city's best! > http://thirdpartyoffers.juno.com/TGL3141/4dde6e8274ec6e98dm03vuc > __ > 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] Amp specs
Well, no. THP's specs are all confusing because they are very cautious to not recommend pushing the amplifiers to their limits. They hope that the users will not push them to the highest level output and thereby minimize the likelihood of over-driving etc. which if not controlled can lead to failures. Solid state amps are much more fragile from this perspective than tube amps. That said, the 1.2KFX is fully capable of 750w key down output. On CW, PEP=AVG. 73, Bob W5OV > could it be that 750 watts PEP is the same as 600 watts key down > > H > > Bob K3DJC > On Thu, 26 May 2011 06:50:48 -0500 "John Harper" writes: >> In looking at several HF amps, I notice that PEP and CW are usually >> of different levels for a given amp. >> >> For example, THP's HL-1.2 is rated at 750w PEP, 600w CW. Granted, a >> receiving station would not notice any difference in a 0.9 dB >> increase of power on any mode but I'm wondering how the KPA500 >> compares - is the 500w rating PEP or CW? >> >> John AE5X >> Radio: 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:Elecraft@mailman.qth.net >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> >> > > > Groupon™ Official Site > 1 ridiculously huge coupon a day. Get 50-90% off your city's best! > http://thirdpartyoffers.juno.com/TGL3141/4dde6e8274ec6e98dm03vuc > __ > 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] Amp specs
could it be that 750 watts PEP is the same as 600 watts key down H Bob K3DJC On Thu, 26 May 2011 06:50:48 -0500 "John Harper" writes: > In looking at several HF amps, I notice that PEP and CW are usually > of different levels for a given amp. > > For example, THP's HL-1.2 is rated at 750w PEP, 600w CW. Granted, a > receiving station would not notice any difference in a 0.9 dB > increase of power on any mode but I'm wondering how the KPA500 > compares - is the 500w rating PEP or CW? > > John AE5X > Radio: 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:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > > Groupon™ Official Site 1 ridiculously huge coupon a day. Get 50-90% off your city's best! http://thirdpartyoffers.juno.com/TGL3141/4dde6e8274ec6e98dm03vuc __ 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] Amp specs
The KPA500 is rated for 500W PEP or CW. Bob, N6CM On Thu, May 26, 2011 at 4:50 AM, John Harper wrote: > In looking at several HF amps, I notice that PEP and CW are usually of > different levels for a given amp. > > For example, THP's HL-1.2 is rated at 750w PEP, 600w CW. Granted, a > receiving station would not notice any difference in a 0.9 dB increase of > power on any mode but I'm wondering how the KPA500 compares - is the 500w > rating PEP or CW? > > John AE5X > Radio: 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: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] Amp specs
In looking at several HF amps, I notice that PEP and CW are usually of different levels for a given amp. For example, THP's HL-1.2 is rated at 750w PEP, 600w CW. Granted, a receiving station would not notice any difference in a 0.9 dB increase of power on any mode but I'm wondering how the KPA500 compares - is the 500w rating PEP or CW? John AE5X Radio: 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:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
