KPA 500

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KPA 500

Albert Crespo
Tokyo High Power has produced a 600 watt amplifier,  HL-550FX , http://www.arraysolutions.com/Products/THPtop.htm   that can handle a wide range of voltages, so it is ideal for places with bad  voltage regulation. Will the  new amplifier that Elecraft will produce will have this same ability?
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Re: KPA 500

juergen piezo
Hi Albert

The old standard of 220,230,240 volts +- 10% has been gradually deteriorating to plus minus anything!

The mains voltages  in many places now goes up to and regularly runs at 260 volts! The global de-regulation and privatization of power assets globally has seen standards  go down the drain everywhere.

Most quality switch mode power supplies are designed for voltages   as high as 260 high volts with a plus 5% rating. Many designers and export countries have not caught up with the global deregulation of mains voltage standards. In many places this has been allowed to happen in the hope that a global standard will develop.

I can buy energy saving globes that are rated to work at 260 volts(Philips). Many  TV's from the Korean companies are designed to  work at 260 volts. There is still a lot of new equipment designed for either 220 and 230 volts nominally. This  well defined standard is hardly the  reality anywhere these days even with the +- 5% allowance


The Tokyo high power amp looks interesting. They appear to be using VRF150's. If they have  biased this amp very well they will achieve good IMD results.  

SPE amplifiers using the MRF150's dont achieve the best IMD performance which can be obtained from  these devices. The Yaesu FT-5000's PA appears to be very well designed. The 3rd order IMD figures in Class AB according to the reviews are almost as low as Class A at 200 watts of output. They use VRF150's This a is a very good achievement by Yaesu and is a benchmark in terms of IMD performance.

I doubt that the Tokyo High power will achieve such good results because THP have always used just the bare minimum bias on all their amp designs. IMD optimization has never been a design goal of theirs. I had a good chat with the designer one day and he was open and candid about this issue.

Mt homebrew MRF150-EB104 amp easily achieves -40db 3rd IMD figures on all bands. My surplus ERB MRI amplifier  which I bought on Ebay does even better than -40db 3rd order. These are all below one of 2 tone figures not PEP figures.

The Elecraft KPA500 will use VRF2933's for which  no IMD data  is provided on the data sheets. I dont know why Microsemi leaves out this important data. Macom religiously supplies extensive IMD data versus bias current which makes choosing devices very easy.  Anyway this will hardly be concern for anyone since the radios always have worst IMD performance than  the amplifiers.

I will watch the reviews and see how they both perform, the market is getting crowded! I will make my donation once I know how well they perform. It would be nice owning a  compact 500 watt amp  that performs well without all the mess and surplus rubbish hanging off the amp.

73
John
 

--- On Sat, 2/5/11, Albert Crespo <[hidden email]> wrote:

> From: Albert Crespo <[hidden email]>
> Subject: [Elecraft] KPA 500
> To: [hidden email]
> Date: Saturday, February 5, 2011, 9:43 AM
> Tokyo High Power has produced a 600
> watt amplifier,  HL-550FX , http://www.arraysolutions.com/Products/THPtop.htm   that
> can handle a wide range of voltages, so it is ideal for
> places with bad  voltage regulation. Will the  new
> amplifier that Elecraft will produce will have this same
> ability?
> ______________________________________________________________
> 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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Re: KPA 500

juergen piezo

Hi Albert

I just looked at the picture of the inside of the THP amp.

http://www.tokyohypower.com/hl-550fx_i_pop.html

I am not impressed with the construction. It looks a lot like an Ameritron inside. At most it looks like a EB104 CCI amp with a power supply and a low pass filter board in a box. The cooling looks to be primitive at best.

I also dont like the switch mode power supply being so close to the high pass  filter board. This is a recipe for noise and other problems. There is also a general lack of shielding. This might be ok for for 500 watt amplifier, however its very ""öpen""

I dont see  real value in this amp especially after looking inside it. I would be more inclined to go buy an Ameritron AlS1300 which represents good value and has similar or better construction. It would certainly have   better overhead in terms of output power.

73
John
--- On Sat, 2/5/11, juergen <[hidden email]> wrote:

> From: juergen <[hidden email]>
> Subject: Re: [Elecraft] KPA 500
> To: [hidden email], "Albert Crespo" <[hidden email]>
> Date: Saturday, February 5, 2011, 3:33 PM
> Hi Albert
>
> The old standard of 220,230,240 volts +- 10% has been
> gradually deteriorating to plus minus anything!
>
> The mains voltages  in many places now goes up to and
> regularly runs at 260 volts! The global de-regulation and
> privatization of power assets globally has seen
> standards  go down the drain everywhere.
>
> Most quality switch mode power supplies are designed for
> voltages   as high as 260 high volts with a
> plus 5% rating. Many designers and export countries have not
> caught up with the global deregulation of mains voltage
> standards. In many places this has been allowed to happen in
> the hope that a global standard will develop.
>
> I can buy energy saving globes that are rated to work at
> 260 volts(Philips). Many  TV's from the Korean
> companies are designed to  work at 260 volts. There is
> still a lot of new equipment designed for either 220 and 230
> volts nominally. This  well defined standard is hardly
> the  reality anywhere these days even with the +- 5%
> allowance
>
>
> The Tokyo high power amp looks interesting. They appear to
> be using VRF150's. If they have  biased this amp very
> well they will achieve good IMD results. 
>
> SPE amplifiers using the MRF150's dont achieve the best IMD
> performance which can be obtained from  these devices.
> The Yaesu FT-5000's PA appears to be very well designed. The
> 3rd order IMD figures in Class AB according to the reviews
> are almost as low as Class A at 200 watts of output. They
> use VRF150's This a is a very good achievement by Yaesu and
> is a benchmark in terms of IMD performance.
>
> I doubt that the Tokyo High power will achieve such good
> results because THP have always used just the bare minimum
> bias on all their amp designs. IMD optimization has never
> been a design goal of theirs. I had a good chat with the
> designer one day and he was open and candid about this
> issue.
>
> Mt homebrew MRF150-EB104 amp easily achieves -40db 3rd IMD
> figures on all bands. My surplus ERB MRI amplifier 
> which I bought on Ebay does even better than -40db 3rd
> order. These are all below one of 2 tone figures not PEP
> figures.
>
> The Elecraft KPA500 will use VRF2933's for which  no
> IMD data  is provided on the data sheets. I dont know
> why Microsemi leaves out this important data. Macom
> religiously supplies extensive IMD data versus bias current
> which makes choosing devices very easy.  Anyway this
> will hardly be concern for anyone since the radios always
> have worst IMD performance than  the amplifiers.
>
> I will watch the reviews and see how they both perform, the
> market is getting crowded! I will make my donation once I
> know how well they perform. It would be nice owning a 
> compact 500 watt amp  that performs well without all
> the mess and surplus rubbish hanging off the amp.
>
> 73
> John
>  
>
> --- On Sat, 2/5/11, Albert Crespo <[hidden email]>
> wrote:
>
> > From: Albert Crespo <[hidden email]>
> > Subject: [Elecraft] KPA 500
> > To: [hidden email]
> > Date: Saturday, February 5, 2011, 9:43 AM
> > Tokyo High Power has produced a 600
> > watt amplifier,  HL-550FX , http://www.arraysolutions.com/Products/THPtop.htm   that
> > can handle a wide range of voltages, so it is ideal
> for
> > places with bad  voltage regulation. Will the  new
> > amplifier that Elecraft will produce will have this
> same
> > ability?
> >
> ______________________________________________________________
> > 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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KPA 500

Johnny Siu
Hello John,

THP is a manufacturer for commercial equipment as well as per their web site. 
I just don't know why their ham amplifiers are so primitive.  They should have
the technology and know how.  My past experience with THP in HF is not
promising. V/U linears are ok.

I would always see linear + ATU as a package.  Therefore, THP + its own
dedicated ATU is not that cheap.  Of course, I shall see how KPA500 + KAT500
come out.

 cheers,


Johnny VR2XMC




________________________________
寄件人﹕ juergen <[hidden email]>
收件人﹕ [hidden email]
傳送日期﹕ 2011/2/6 (日) 7:46:49 AM
主題: Re: [Elecraft] KPA 500


Hi Albert

I just looked at the picture of the inside of the THP amp.

http://www.tokyohypower.com/hl-550fx_i_pop.html

I am not impressed with the construction. It looks a lot like an Ameritron
inside. At most it looks like a EB104 CCI amp with a power supply and a low pass
filter board in a box. The cooling looks to be primitive at best.

I also dont like the switch mode power supply being so close to the high pass 
filter board. This is a recipe for noise and other problems. There is also a
general lack of shielding. This might be ok for for 500 watt amplifier, however
its very ""öpen""

I dont see  real value in this amp especially after looking inside it. I would
be more inclined to go buy an Ameritron AlS1300 which represents good value and
has similar or better construction. It would certainly have  better overhead in
terms of output power.

73
John
--- On Sat, 2/5/11, juergen <[hidden email]> wrote:

> From: juergen <[hidden email]>
> Subject: Re: [Elecraft] KPA 500
> To: [hidden email], "Albert Crespo" <[hidden email]>
> Date: Saturday, February 5, 2011, 3:33 PM
> Hi Albert
>
> The old standard of 220,230,240 volts +- 10% has been
> gradually deteriorating to plus minus anything!
>
> The mains voltages  in many places now goes up to and
> regularly runs at 260 volts! The global de-regulation and
> privatization of power assets globally has seen
> standards  go down the drain everywhere.
>
> Most quality switch mode power supplies are designed for
> voltages   as high as 260 high volts with a
> plus 5% rating. Many designers and export countries have not
> caught up with the global deregulation of mains voltage
> standards. In many places this has been allowed to happen in
> the hope that a global standard will develop.
>
> I can buy energy saving globes that are rated to work at
> 260 volts(Philips). Many  TV's from the Korean
> companies are designed to  work at 260 volts. There is
> still a lot of new equipment designed for either 220 and 230
> volts nominally. This  well defined standard is hardly
> the  reality anywhere these days even with the +- 5%
> allowance
>
>
> The Tokyo high power amp looks interesting. They appear to
> be using VRF150's. If they have  biased this amp very
> well they will achieve good IMD results. 
>
> SPE amplifiers using the MRF150's dont achieve the best IMD
> performance which can be obtained from  these devices.
> The Yaesu FT-5000's PA appears to be very well designed. The
> 3rd order IMD figures in Class AB according to the reviews
> are almost as low as Class A at 200 watts of output. They
> use VRF150's This a is a very good achievement by Yaesu and
> is a benchmark in terms of IMD performance.
>
> I doubt that the Tokyo High power will achieve such good
> results because THP have always used just the bare minimum
> bias on all their amp designs. IMD optimization has never
> been a design goal of theirs. I had a good chat with the
> designer one day and he was open and candid about this
> issue.
>
> Mt homebrew MRF150-EB104 amp easily achieves -40db 3rd IMD
> figures on all bands. My surplus ERB MRI amplifier 
> which I bought on Ebay does even better than -40db 3rd
> order. These are all below one of 2 tone figures not PEP
> figures.
>
> The Elecraft KPA500 will use VRF2933's for which  no
> IMD data  is provided on the data sheets. I dont know
> why Microsemi leaves out this important data. Macom
> religiously supplies extensive IMD data versus bias current
> which makes choosing devices very easy.  Anyway this
> will hardly be concern for anyone since the radios always
> have worst IMD performance than  the amplifiers.
>
> I will watch the reviews and see how they both perform, the
> market is getting crowded! I will make my donation once I
> know how well they perform. It would be nice owning a 
> compact 500 watt amp  that performs well without all
> the mess and surplus rubbish hanging off the amp.
>
> 73
> John

>
> --- On Sat, 2/5/11, Albert Crespo <[hidden email]>
> wrote:
>
> > From: Albert Crespo <[hidden email]>
> > Subject: [Elecraft] KPA 500
> > To: [hidden email]
> > Date: Saturday, February 5, 2011, 9:43 AM
> > Tokyo High Power has produced a 600
> > watt amplifier,  HL-550FX ,
>http://www.arraysolutions.com/Products/THPtop.htm   that
> > can handle a wide range of voltages, so it is ideal
> for
> > places with bad  voltage regulation. Will the  new
> > amplifier that Elecraft will produce will have this
> same
> > ability?
> >
> ______________________________________________________________
> > 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



     
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Re: KPA 500

ac0h
THP's amps are anything but primitive.
Check me if I'm wrong but they are the only manufacturer producing a
legal limit solid state amp. The THP 2.5KFX.

Notice I said legal limit, not close to or in the neighborhood, or
might make it if the wind blows just right, but legal limit.

The design for that amp was hashed out on the pages of QEX.

It is expensive but not Alpha 9500 expensive and it is one of a kind.

Why hasn't anybody else designed a legal limit solid state amp?
8 MRF-150's are about the same price as 2 Microsemi ARF-1500's
50V high current DC supply vs 200V high current DC supply (in the box).
Same stupid proof auto-protection systems all the other "not quite
there" amps employ. Well, maybe not. I don't think any of the MFJ amps
will auto band switch without buying their little add-on decoder.

What was that about primitive?



On Sun, 6 Feb 2011 07:58:06 +0800 (HKT)
Johnny Siu <[hidden email]> wrote:

> Hello John,
>
> THP is a manufacturer for commercial equipment as well as per
> their web site. I just don't know why their ham amplifiers are so
> primitive.  They should have the technology and know how.  My past
> experience with THP in HF is not promising. V/U linears are ok.
>
> I would always see linear + ATU as a package.  Therefore, THP + its
> own dedicated ATU is not that cheap.  Of course, I shall see how
> KPA500 + KAT500 come out.
>
>  cheers,
>
>
> Johnny VR2XMC



--
R. Kevin Stover
AC0H
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Re: KPA 500

Joe Subich, W4TV-4

 > Why hasn't anybody else designed a legal limit solid state amp?
 > 8 MRF-150's are about the same price as 2 Microsemi ARF-1500's
 > 50V high current DC supply vs 200V high current DC supply (in
 > the box).

8 MRF-150 will not do the job ... that's what is in the ALS-1300
and it's good for 1200 Watts.  Legal limit would take 12 MRF-150.

73,

    ... Joe, W4TV

On 2/5/2011 7:30 PM, R. Kevin Stover wrote:

> THP's amps are anything but primitive.
> Check me if I'm wrong but they are the only manufacturer producing a
> legal limit solid state amp. The THP 2.5KFX.
>
> Notice I said legal limit, not close to or in the neighborhood, or
> might make it if the wind blows just right, but legal limit.
>
> The design for that amp was hashed out on the pages of QEX.
>
> It is expensive but not Alpha 9500 expensive and it is one of a kind.
>
> Why hasn't anybody else designed a legal limit solid state amp?
> 8 MRF-150's are about the same price as 2 Microsemi ARF-1500's
> 50V high current DC supply vs 200V high current DC supply (in the box).
> Same stupid proof auto-protection systems all the other "not quite
> there" amps employ. Well, maybe not. I don't think any of the MFJ amps
> will auto band switch without buying their little add-on decoder.
>
> What was that about primitive?
>
>
>
> On Sun, 6 Feb 2011 07:58:06 +0800 (HKT)
> Johnny Siu<[hidden email]>  wrote:
>
>> Hello John,
>>
>> THP is a manufacturer for commercial equipment as well as per
>> their web site. I just don't know why their ham amplifiers are so
>> primitive.  They should have the technology and know how.  My past
>> experience with THP in HF is not promising. V/U linears are ok.
>>
>> I would always see linear + ATU as a package.  Therefore, THP + its
>> own dedicated ATU is not that cheap.  Of course, I shall see how
>> KPA500 + KAT500 come out.
>>
>>   cheers,
>>
>>
>> Johnny VR2XMC
>
>
>
______________________________________________________________
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Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

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Re: KPA 500

Bob Naumann W5OV
In reply to this post by juergen piezo
John,

What are your credentials for such a critique without having actually seen
or used the amplifier, and what is your callsign?

73,

Bob W5OV


-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of juergen
Sent: Saturday, February 05, 2011 5:47 PM
To: [hidden email]
Subject: Re: [Elecraft] KPA 500


Hi Albert

I just looked at the picture of the inside of the THP amp.

http://www.tokyohypower.com/hl-550fx_i_pop.html

I am not impressed with the construction. It looks a lot like an Ameritron
inside. At most it looks like a EB104 CCI amp with a power supply and a low
pass filter board in a box. The cooling looks to be primitive at best.

I also dont like the switch mode power supply being so close to the high
pass  filter board. This is a recipe for noise and other problems. There is
also a general lack of shielding. This might be ok for for 500 watt
amplifier, however its very ""öpen""

I dont see  real value in this amp especially after looking inside it. I
would be more inclined to go buy an Ameritron AlS1300 which represents good
value and has similar or better construction. It would certainly have
better overhead in terms of output power.

73
John
--- On Sat, 2/5/11, juergen <[hidden email]> wrote:

> From: juergen <[hidden email]>
> Subject: Re: [Elecraft] KPA 500
> To: [hidden email], "Albert Crespo" <[hidden email]>
> Date: Saturday, February 5, 2011, 3:33 PM
> Hi Albert
>
> The old standard of 220,230,240 volts +- 10% has been
> gradually deteriorating to plus minus anything!
>
> The mains voltages  in many places now goes up to and
> regularly runs at 260 volts! The global de-regulation and
> privatization of power assets globally has seen
> standards  go down the drain everywhere.
>
> Most quality switch mode power supplies are designed for
> voltages   as high as 260 high volts with a
> plus 5% rating. Many designers and export countries have not
> caught up with the global deregulation of mains voltage
> standards. In many places this has been allowed to happen in
> the hope that a global standard will develop.
>
> I can buy energy saving globes that are rated to work at
> 260 volts(Philips). Many  TV's from the Korean
> companies are designed to  work at 260 volts. There is
> still a lot of new equipment designed for either 220 and 230
> volts nominally. This  well defined standard is hardly
> the  reality anywhere these days even with the +- 5%
> allowance
>
>
> The Tokyo high power amp looks interesting. They appear to
> be using VRF150's. If they have  biased this amp very
> well they will achieve good IMD results. 
>
> SPE amplifiers using the MRF150's dont achieve the best IMD
> performance which can be obtained from  these devices.
> The Yaesu FT-5000's PA appears to be very well designed. The
> 3rd order IMD figures in Class AB according to the reviews
> are almost as low as Class A at 200 watts of output. They
> use VRF150's This a is a very good achievement by Yaesu and
> is a benchmark in terms of IMD performance.
>
> I doubt that the Tokyo High power will achieve such good
> results because THP have always used just the bare minimum
> bias on all their amp designs. IMD optimization has never
> been a design goal of theirs. I had a good chat with the
> designer one day and he was open and candid about this
> issue.
>
> Mt homebrew MRF150-EB104 amp easily achieves -40db 3rd IMD
> figures on all bands. My surplus ERB MRI amplifier 
> which I bought on Ebay does even better than -40db 3rd
> order. These are all below one of 2 tone figures not PEP
> figures.
>
> The Elecraft KPA500 will use VRF2933's for which  no
> IMD data  is provided on the data sheets. I dont know
> why Microsemi leaves out this important data. Macom
> religiously supplies extensive IMD data versus bias current
> which makes choosing devices very easy.  Anyway this
> will hardly be concern for anyone since the radios always
> have worst IMD performance than  the amplifiers.
>
> I will watch the reviews and see how they both perform, the
> market is getting crowded! I will make my donation once I
> know how well they perform. It would be nice owning a 
> compact 500 watt amp  that performs well without all
> the mess and surplus rubbish hanging off the amp.
>
> 73
> John
>  
>
> --- On Sat, 2/5/11, Albert Crespo <[hidden email]>
> wrote:
>
> > From: Albert Crespo <[hidden email]>
> > Subject: [Elecraft] KPA 500
> > To: [hidden email]
> > Date: Saturday, February 5, 2011, 9:43 AM
> > Tokyo High Power has produced a 600
> > watt amplifier,  HL-550FX ,
http://www.arraysolutions.com/Products/THPtop.htm   that

> > can handle a wide range of voltages, so it is ideal
> for
> > places with bad  voltage regulation. Will the  new
> > amplifier that Elecraft will produce will have this
> same
> > ability?
> >
> ______________________________________________________________
> > 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
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Re: KPA 500

David Cutter
In reply to this post by juergen piezo
I can't speak for other countries, but here in the UK I used 240V +-7%
(223V to 257V) for normal service but for brown to peak I used 240V +-10%
(216 to 264V), which is very rarely seen here.  The 264V is used to test
safety trips and the like according to British Standards such as the the
generic BS3456.  Factoring Europe into the equation, I reduce the lower band
to 198V (220 - 10%), so, my designs covered 198 to 264V for safe and
reliable operation.  In practice, the lower end often extended to 186V
(-15%).  This puts quite a burden on dissipating heat at the top end when
using linear supplies, but is the penalty when designing for extremes if
switchmode cannot be used. Hence tapped transformers to cope with local
supplies.

Being aware of this, I have always been wary of generators when /P or
dxpeditioning and with valve linears getting the heater voltage right with a
true rms voltmeter has always been a concern for me.  Small generators often
produce more of a triangular waveform and are poorly regulated well beyond
+-10% key up to key down.  With a transistor linear I am concerned about the
peak of the triangle which is higher than that of a sinewave of the same rms
voltage, so, component ratings are very important.  On full load, the
problem is distortion as the incoming voltage drops.  Some generators also
slow down, increasing the ripple triangle and current into the reservoir
caps.

David
G3UNA
My previous email on this didn't appear on the list, perhaps stuck in
cyberspace.


snip from Juergen


Hi Albert

The old standard of 220,230,240 volts +- 10% has been gradually
deteriorating to plus minus anything!

The mains voltages  in many places now goes up to and regularly runs at 260
volts! The global de-regulation and privatization of power assets globally
has seen standards  go down the drain everywhere.

Most quality switch mode power supplies are designed for voltages   as high
as 260 high volts with a plus 5% rating. Many designers and export countries
have not caught up with the global deregulation of mains voltage standards.
In many places this has been allowed to happen in the hope that a global
standard will develop.
.

73
John


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Re: KPA 500

M0XDF
I get 240 +- 2v here in Bracknell in Berkshire.
73 de M0XDF, K3 #174, P3 #108
--
No sensible decision can be made any longer without taking into account not
only the world as it is, but the world as it will be.
-Isaac Asimov, scientist and writer (1920-1992)

On 6 Feb 2011, at 09:36, David Cutter wrote:

> I can't speak for other countries, but here in the UK I used 240V +-7%
> (223V to 257V) for normal service but for brown to peak I used 240V +-10%
> (216 to 264V), which is very rarely seen here.  The 264V is used to test
> safety trips and the like according to British Standards such as the the
> generic BS3456.  Factoring Europe into the equation, I reduce the lower band
> to 198V (220 - 10%), so, my designs covered 198 to 264V for safe and
> reliable operation.  In practice, the lower end often extended to 186V
> (-15%).  This puts quite a burden on dissipating heat at the top end when
> using linear supplies, but is the penalty when designing for extremes if
> switchmode cannot be used. Hence tapped transformers to cope with local
> supplies.
>
> Being aware of this, I have always been wary of generators when /P or
> dxpeditioning and with valve linears getting the heater voltage right with a
> true rms voltmeter has always been a concern for me.  Small generators often
> produce more of a triangular waveform and are poorly regulated well beyond
> +-10% key up to key down.  With a transistor linear I am concerned about the
> peak of the triangle which is higher than that of a sinewave of the same rms
> voltage, so, component ratings are very important.  On full load, the
> problem is distortion as the incoming voltage drops.  Some generators also
> slow down, increasing the ripple triangle and current into the reservoir
> caps.
>
> David
> G3UNA
> My previous email on this didn't appear on the list, perhaps stuck in
> cyberspace.
>
>
> snip from Juergen
>
>
> Hi Albert
>
> The old standard of 220,230,240 volts +- 10% has been gradually
> deteriorating to plus minus anything!
>
> The mains voltages  in many places now goes up to and regularly runs at 260
> volts! The global de-regulation and privatization of power assets globally
> has seen standards  go down the drain everywhere.
>
> Most quality switch mode power supplies are designed for voltages   as high
> as 260 high volts with a plus 5% rating. Many designers and export countries
> have not caught up with the global deregulation of mains voltage standards.
> In many places this has been allowed to happen in the hope that a global
> standard will develop.
> .
>
> 73
> John
>
>
> ______________________________________________________________
> 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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