[Elecraft] Fwd: New Sherwood report

Wed Dec 1 22:11:42 EST 2010

 > The Ft5000 has better PA than the K3. Its IMD performance is way
 > superior to the K3 especially on the higher bands and 6 meters. It
 > smacks of double standards harping on about Yaesu Keyclicks and
 > ignoring SSB transmitter IMD especially on the K3 when it is so
 > marginal.

The FT-5000 has better transmit IMD because it uses 48V FETs.  Those
Yaesu (and other manufacturers) transmitters that use 12V PA devices
transistors are no better - perhaps marginally worse than the K3.

 > I wish Elecraft would release a better PA using fets for the K3.

12V FETs would not produce any better IMD than the 2SC2782 used
in the K3 ... compare the MRF255 (12.5V VMOS FET) with its typical
-30 dBc IMD3 at 100 W PEP for a pair (-32 dBc at transmitter output
for TPO below 80 watts PEP).

Would I like Elecraft to provide a high voltage PA option - yes!
However, you must compare apples to apples - in this case 12V PA
devices to 12 V PA devices - and although the K3 PA is not as clean
as the 200 W 50V devices, it provides a level that is generally
acceptable in amateur service for 12V devices.

If you want to complain about "dirty" transmitters, start with a
campaign to get all the unmodified FT-1000D, FT-1000 MP, MK V
recalled by their manufacturer to fix the key clicks.  Start a
campaign to get all the IC-746/7400 recalled to fix their horribly
noisy LO (transmitted phase noise).  Start a campaign to get many
of the other 12V PA rigs with TX IMD *worse* than the K3 recalled.
Sure, even start a campaign to convince owners of 12V PA rigs to
keep their power output below 75W PEP ... all of those would go a
lot farther in cleaning up the bands than complaining about the
K3 transmit IMD.

73,

    ... Joe, W4TV

On 12/1/2010 9:27 PM, juergen wrote:
> Hi Ken
>
> The Ft5000 has better PA than the K3. Its IMD performance is way superior to the K3 especially on the higher bands and 6 meters. It smacks of double standards harping on about Yaesu Keyclicks and ignoring SSB transmitter IMD especially on the K3 when it is so marginal.
>
> Unnecessary wide transmission on any mode is bad for all of us.
> The key click issue and SSB IMD issue has same bad effect.
> Its wise not to throw stones in glass houses.
>
> I wish Elecraft would release a better PA using fets for the K3.
>
> The Yaesu FT5000 certainly has a better PA than the K3.
>
> The Ft5000 has superb transmitter IMD, far superior to the K3's transmitter.
>
> I find it interesting that so many observers harp endlessly about the Yaesu
> Keyclick problems and totally  ignore the issue of the K3's poor SSB IMD.
>
> The Yaesu Ft5000 has the edge in this department.
>
> 73
> John
> --- On Wed, 12/1/10, K9ZTV<k9ztv at socket.net>  wrote:
>
>> From: K9ZTV<k9ztv at socket.net>
>> Subject: Re: [Elecraft] Fwd: New Sherwood report
>> To: "elecraft at mailman.qth.net"<elecraft at mailman.qth.net>
>> Date: Wednesday, December 1, 2010, 2:26 PM
>> I agree.
>>
>> Where is the edging out?
>>
>> Sherwood sorts on Dynamic Range-Narrow Spaced, and both
>> rigs are 101db
>> at 2 Kcs.
>>
>> I'm confused by Bob's statement that it "edges out" the
>> K3.
>>
>> If you take the other parameters into consideration, the K3
>> should be
>> listed first and the 5000 listed second.
>>
>> 73,
>>
>> Kent  K9ZTV
>>
>>
>> On 12/1/2010 3:18 PM, Wayne Burdick wrote:
>>> Pretty close to a dead heat between the K3 and the
>> FT5000, except for blocking dynamic range (K3 is better by
>> 13 dB) and filter ultimate attenuation (K3 is better by 15
>> dB).
>>>
>>> Not bad for a 9-pound rig that starts at $1400.
>>>
>>> That said, I will now disqualify myself from the rest
>> of this thread :)
>>>
>>> 73,
>>> Wayne
>>> N6KR
>>>
>>>     Ed wrote:
>>>
>>>> http://www.sherweng.com/table.html
>>>
>> ______________________________________________________________
>>> Elecraft mailing list
>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>> Help: http://mailman.qth.net/mmfaq.htm
>>> Post: mailto:Elecraft at mailman.qth.net
>>>
>>> This list hosted by: http://www.qsl.net
>>> Please help support this email list: http://www.qsl.net/donate.html
>>>
>>>
>>>
>>>
>>>
>>>
>>> -----
>>> No virus found in this message.
>>> Checked by AVG - www.avg.com
>>> Version: 10.0.1170 / Virus Database: 426/3291 -
>> Release Date: 12/01/10
>>>
>>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:Elecraft at 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 at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>