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Does KPA1500 have these KPA500 characteristics?

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Does KPA1500 have these KPA500 characteristics?

While trying to run my KPA500 at full-tilt--but as cool as possible--in digital modes, I have noticed over the years that:
1). The KPA500 actually runs cooler at just-below-fault power output than it does at either 500 or even 400 watts output.
2) The KPA500 runs substanitally cooler at a 1:1 SWR than it does at even 1.2:1.
Does the KPA1500 also do this? I'd appreciate actual experience more than conjecture.
Thanks and 73,
Eric WD6DBM

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Bob McGraw - K4TAX

Re: Does KPA1500 have these KPA500 characteristics?

Eric, et & al:

I have a KPA500 on the desk. It is about 1 month old.   As to
efficiency which is related to power output vs. power input, a simple
ohms law calculation is all that's needed to see what is occurring.
During transmit, note the value of HV and the value of CURRENT. Also
note the power output in watts. All of these values are on the LCD
display.    Per Ohms law, Volts x Current = watts which is DC watts
input. Then Power output ÷ DC watts input X 100 = % efficiency.

With my amp in CW mode key down on 80M:   Voltage = 63.0, Current = 12.1
amps, RF power output is 575 watts.   Thus 63.0 x 12.1 = 762.3 watts DC
power input.    Then 575/763.3 = .7533 x 100 = 75.33%. In this
configuration 762.3 - 575 = 187.3 watts of required heat dissipation.

Now at a lower power output on 80M: Voltage is 64.6, Current is 8.8
amps, RF power output is 300 watts.   Thus 64.6 x 8.8 = 568.5 watts DC
power input.   Then 300/568.5 = .5277 x 100 = 52.77% In this
configuration 268.5 watts of required heat dissipation.

My power measurements are made using my Bird 43 and a 50.5 ohm dummy
load.   I have not done a calibration on the KPA500 power meter,
although I find it relatively accurate.

Now in each case, the difference between RF power output and DC power
input is the watts of heat that will be dissipated. Yes, it is clear
that running the amp at higher power, but never to exceed the rating nor
temperature limits is the more efficient method. By the way, those hams
that run their tube amps at reduced power "to save the tubes" are in
fact doing just the opposite in as much as the efficiency at lower power
is less than at higher power. The heat has to go somewhere and it ends
up in the amp or being exhausted by the cooling system.

As to running the amp at 500 watts, or 600 watts or 700 watts, thus just
before fault power, I would need to examine the IMD products to be
confident the amp is "clean". A solid state amp which is being over
driven just a wee bit can get really nasty on the air and real fast.
The product is splatter on either side of the operating frequency.
Avoid this and sacrifice a few watts of output power.

As to the KPA1500, I have no experience or knowledge. But I would say
it follows the same rational of operating and efficiency.

73

Bob, K4TAX

On 5/24/2018 7:54 PM, eric norris via Elecraft wrote:

> While trying to run my KPA500 at full-tilt--but as cool as possible--in digital modes, I have noticed over the years that:
> 1). The KPA500 actually runs cooler at just-below-fault power output than it does at either 500 or even 400 watts output.
> 2) The KPA500 runs substanitally cooler at a 1:1 SWR than it does at even 1.2:1.
> Does the KPA1500 also do this? I'd appreciate actual experience more than conjecture.
> Thanks and 73,
> Eric WD6DBM
>
> Sent from Yahoo Mail on Android
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Wes Stewart-2

Re: Does KPA1500 have these KPA500 characteristics?

I haven't measured IMD on my KPA500 either since I don't own two generators that
are clean enough with the necessary power to do so.

I would suspect, however, that the amp is cleaner that a K3(S) driving it.

Wes N7WS

On 5/24/2018 7:01 PM, Bob McGraw K4TAX wrote:

> ....
>
> As to running the amp at 500 watts, or 600 watts or 700 watts, thus just
> before fault power, I would need to examine the IMD products to be confident
> the amp is "clean". A solid state amp which is being over driven just a wee
> bit can get really nasty on the air and real fast. The product is splatter on
> either side of the operating frequency. Avoid this and sacrifice a few watts
> of output power.
>
> As to the KPA1500, I have no experience or knowledge. But I would say it
> follows the same rational of operating and efficiency.
>
> 73
>
> Bob, K4TAX

Jim Brown-10

Re: Does KPA1500 have these KPA500 characteristics?

On 5/24/2018 7:30 PM, Wes Stewart wrote:
> I haven't measured IMD on my KPA500 either since I don't own two
> generators that are clean enough with the necessary power to do so.

I evaluate IMD by looking at keying sidebands of a long series of dits,
as I posted hear yesterday. Details of the measurement setup and
method, and lots of results, are here.
http://k9yc.com/P3_Spectrum_Measurements.pdf

It's well known that IMD in the K3/K3S increases at rated output, and is
a lot lower at the levels needed to drive a power amp. It takes 25-30W
to drive the KPA500 to full power, and about twice that to drive my Ten
Tec Titans. The K3/K3S is pretty clean at these levels. The plots for
the two amps look almost exactly the same, and have the same shape as
the K3 at those drive levels.In other words, neither amp is increasing
bandwidth. Note that these measurements are of the envelope of peaks, so
they are, in essence, capturing clicks.

IMD also increases with low DC supply voltage. I've not done any
disciplined measurements to put numbers to it, but K6XX has. His data is
in this pdf slide show. http://k9yc.com/K6XXAmpTalk.pdf

73, Jim K9YC

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ANDY DURBIN

Does KPA1500 have these KPA500 characteristics?

In reply to this post by Elecraft mailing list

"The KPA500 actually runs cooler at just-below-fault power output than it does at either 500 or even 400 watts output."

I ran a quick test to see if I saw the similar results with my KPA500. The quality of the data is limited by the low resolution of power returned by the ^WS command but it shows that PA heating is 350 +/- 25 W for all output power levels between 150 W and 500 W. Below 150 W the PA heating falls off with power output. The cluster of points close to 500 W lies at about 330 W heating which does support the idea that PA heating will be less at max power output. I did not extend the test beyond 500 W output.

I may try the test again with a better controlled drive ramp rate but the quality will still be limited by the resolution of power returned by ^WS. To get better results I'll need to expand my logger capabilities to include sampling of my LP-100A power data.

73,

Andy, k3wyc

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K9MA

Re: Does KPA1500 have these KPA500 characteristics?

On 5/25/2018 09:15, ANDY DURBIN wrote:
> "The KPA500 actually runs cooler at just-below-fault power output than it does at either 500 or even 400 watts output."

That's to be expected of any class AB power amplifier. The dissipation
may actually be lowest when it is driven into saturation, not
recommended for any mode except CW. And even on CW, it could generate
key clicks.

73,

Scott K9MA

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Wes Stewart-2

Re: Does KPA1500 have these KPA500 characteristics?

In reply to this post by Jim Brown-10

I have no idea what you are actually measuring but it certainly isn't IMD in the
classical sense. While it might be "well known" that IMD decreases at lower
power, it isn't necessarily true. What is really not well known is that in the
K3(S) IMD is highly frequency sensitive. The 3rd order IMD in my K3S at 10W
output varies 18 dB with respect to frequency.

Furthermore, my K3S on 10, 17, 20, 30 and 40-meters has higher IMD at 20W than
at 100W.

Wes N7WS

On 5/24/2018 8:17 PM, Jim Brown wrote:

> On 5/24/2018 7:30 PM, Wes Stewart wrote:
>> I haven't measured IMD on my KPA500 either since I don't own two generators
>> that are clean enough with the necessary power to do so.
>
> I evaluate IMD by looking at keying sidebands of a long series of dits, as I
> posted hear yesterday. Details of the measurement setup and method, and lots
> of results, are here. http://k9yc.com/P3_Spectrum_Measurements.pdf
>
> It's well known that IMD in the K3/K3S increases at rated output, and is a lot
> lower at the levels needed to drive a power amp. It takes 25-30W to drive the
> KPA500 to full power, and about twice that to drive my Ten Tec Titans. The
> K3/K3S is pretty clean at these levels. The plots for the two amps look almost
> exactly the same, and have the same shape as the K3 at those drive levels.In
> other words, neither amp is increasing bandwidth. Note that these measurements
> are of the envelope of peaks, so they are, in essence, capturing clicks.
>
> IMD also increases with low DC supply voltage. I've not done any disciplined
> measurements to put numbers to it, but K6XX has. His data is in this pdf slide
> show. http://k9yc.com/K6XXAmpTalk.pdf
>
> 73, Jim K9YC

Jim Brown-10

Re: Does KPA1500 have these KPA500 characteristics?

On 5/25/2018 1:43 PM, Wes Stewart wrote:
> I have no idea what you are actually measuring but it certainly isn't
> IMD in the classical sense.

I think I made it plain that I was measuring the "envelope" of keying
sidebands, usually described as "clicks." This envelope is due to a
combination of the shape of the keying waveform and IMD.

FWIW, I really don't care about IMD as a number. What I'm concerned with
is clicks, splatter, and phase noise from another station that's loud
covering a weaker station I want to work.

> While it might be "well known" that IMD decreases at lower power, it
> isn't necessarily true.

Right -- it depends on the transmitter design and implementation. K6XX's
work shows that to be true of the K3, and my measurements (done on 20M
as I recall) confirmed it. I also recall that you noted increased IMD
around 15W, which is likely the result of the K3 firmware causing the
power amp to be turned off and the QRP output stage to be driving the
load at it's full rated power. Under that condition it is consistent
with my (and K6XX's) observations that IMD is often lower at reduced
power output.

> What is really not well known is that in the K3(S) IMD is highly
> frequency sensitive.

That's news to me.

> The 3rd order IMD in my K3S at 10W output varies 18 dB with respect to
> frequency.

Again, the power amp is not engaged and you're running on the driver.
But that much variation also implies a problem. Have you sent the rig
back to Elecraft?

> Furthermore, my K3S on 10, 17, 20, 30 and 40-meters has higher IMD at
> 20W than at 100W.

Interesting.

73, Jim

>
> Wes N7WS
>
> On 5/24/2018 8:17 PM, Jim Brown wrote:
>> On 5/24/2018 7:30 PM, Wes Stewart wrote:
>>> I haven't measured IMD on my KPA500 either since I don't own two
>>> generators that are clean enough with the necessary power to do so.
>>
>> I evaluate IMD by looking at keying sidebands of a long series of
>> dits, as I posted hear yesterday. Details of the measurement setup
>> and method, and lots of results, are here.
>> http://k9yc.com/P3_Spectrum_Measurements.pdf
>>
>> It's well known that IMD in the K3/K3S increases at rated output, and
>> is a lot lower at the levels needed to drive a power amp. It takes
>> 25-30W to drive the KPA500 to full power, and about twice that to
>> drive my Ten Tec Titans. The K3/K3S is pretty clean at these levels.
>> The plots for the two amps look almost exactly the same, and have the
>> same shape as the K3 at those drive levels.In other words, neither
>> amp is increasing bandwidth. Note that these measurements are of the
>> envelope of peaks, so they are, in essence, capturing clicks.
>>
>> IMD also increases with low DC supply voltage. I've not done any
>> disciplined measurements to put numbers to it, but K6XX has. His data
>> is in this pdf slide show. http://k9yc.com/K6XXAmpTalk.pdf
>>
>> 73, Jim K9YC

Bill K9YEQ

Re: Does KPA1500 have these KPA500 characteristics?

In reply to this post by K9MA

For those of us who can be slow: operate as designed? :-)

72 & 73,
Bill
K9YEQ
FT’er for K2, KX1, KX3, KXPA100, KAT500, W2, etc.

-----Original Message-----
From: [hidden email] <[hidden email]> On Behalf Of K9MA
Sent: Friday, May 25, 2018 11:36 AM
To: [hidden email]
Subject: Re: [Elecraft] Does KPA1500 have these KPA500 characteristics?

On 5/25/2018 09:15, ANDY DURBIN wrote:
> "The KPA500 actually runs cooler at just-below-fault power output than it does at either 500 or even 400 watts output."

That's to be expected of any class AB power amplifier. The dissipation may actually be lowest when it is driven into saturation, not recommended for any mode except CW. And even on CW, it could generate key clicks.

73,

Scott K9MA

--
Scott K9MA

[hidden email]

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Bill Frantz

Re: Does KPA1500 have these KPA500 characteristics?

In reply to this post by Jim Brown-10

In casual conversation, I had an Elecraft developer suggest that
to minimize IMD, you don't want to drive an amplifier with the
K3 output power near the top of the QRP amp range (just below 12
or 13 watts). I generally stay below 10 watts, but would like to
have the 100W amplifier automatically engaged if that will
reduce IMD.

Note: I am sometimes driving my Expert 1.3K amp to 100 watts
output on FT8 just to save the batteries powering my K3. It also
makes it easy to QRO, and I have a couple of FT8 contacts in my
log -- with a DU and a JA -- reporting me at -24 dB where I was
operating at 800 watts. YMMV.

73 Bill AE6JV

On 5/25/18 at 2:25 PM, [hidden email] (Jim Brown) wrote:

>Right -- it depends on the transmitter design and
>implementation. K6XX's work shows that to be true of the K3,
>and my measurements (done on 20M as I recall) confirmed it. I
>also recall that you noted increased IMD around 15W, which is
>likely the result of the K3 firmware causing the power amp to
>be turned off and the QRP output stage to be driving the load
>at it's full rated power. Under that condition it is consistent
>with my (and K6XX's) observations that IMD is often lower at
>reduced power output.

-----------------------------------------------------------------------
Bill Frantz | Concurrency is hard. 12 out | Periwinkle
(408)356-8506 | 10 programmers get it wrong. | 16345
Englewood Ave
www.pwpconsult.com | - Jeff Frantz | Los Gatos,
CA 95032

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Richard-6

Too Much Power

“I have a couple of FT8 contacts in my log -- with a DU and a JA -- reporting me at -24 dB where I WAS OPERATING AT 800 WATTS. YMMV.”

Why do you think you need 800 watts in a weak signal mode? Do you have any idea what that does to other operators? I’ve made several 10,000+ mile contacts with 50 watts, as have others who are following the “rules.”
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Jack Brindle-2

Re: Too Much Power

I’ve seen Bill’s setup. 50 watts with a decent gain antenna (i.e. beam) is equivalent to 800 watts with Bill’s antenna and QTH. He really has done an outstanding job with the resources he has to work with.
Also remember, we are talking about a 4 to 5 db difference in power here. And when you have pretty large mountains blocking your path to JA and EU, that 4db of power can make a huge difference.
QTH and the antenna system really make a huge difference!

73,
Jack, W6FB

> On May 25, 2018, at 4:15 PM, Richard <[hidden email]> wrote:
>
> “I have a couple of FT8 contacts in my log -- with a DU and a JA -- reporting me at -24 dB where I WAS OPERATING AT 800 WATTS. YMMV.”
>
> Why do you think you need 800 watts in a weak signal mode? Do you have any idea what that does to other operators? I’ve made several 10,000+ mile contacts with 50 watts, as have others who are following the “rules.”
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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Wes Stewart-2

Re: Does KPA1500 have these KPA500 characteristics?

In reply to this post by Jim Brown-10

Violating guidelines and replying inline.

On 5/25/2018 2:25 PM, Jim Brown wrote:
> On 5/25/2018 1:43 PM, Wes Stewart wrote:
>> I have no idea what you are actually measuring but it certainly isn't IMD in
>> the classical sense.
>
> I think I made it plain that I was measuring the "envelope" of keying
> sidebands, usually described as "clicks." This envelope is due to a
> combination of the shape of the keying waveform and IMD.

Actually, you said below, "I evaluate IMD blah blah..."
>
> FWIW, I really don't care about IMD as a number. What I'm concerned with is
> clicks, splatter, and phase noise from another station that's loud covering a
> weaker station I want to work.

Since the numbers are more-or-less specified by Elecraft I'll go by them. I say
more-or-less because they don't actually have a firm specs.

>
>> While it might be "well known" that IMD decreases at lower power, it isn't
>> necessarily true.
>
> Right -- it depends on the transmitter design and implementation. K6XX's work
> shows that to be true of the K3, and my measurements (done on 20M as I recall)
> confirmed it. I also recall that you noted increased IMD around 15W, which is
> likely the result of the K3 firmware causing the power amp to be turned off
> and the QRP output stage to be driving the load at it's full rated power.
> Under that condition it is consistent with my (and K6XX's) observations that
> IMD is often lower at reduced power output.

You recall incorrectly. First, I've never stated that and second, the HPA
engages at 12 W. I have however, stated in strong terms several times in this
and other forums that a K3 should never be operated above 10W on the LPA. I and
others have asked for a firmware change that would insure this.
>
>> What is really not well known is that in the K3(S) IMD is highly frequency
>> sensitive.
>
> That's news to me.

Well even experts can learn something new now and again.
>
>> The 3rd order IMD in my K3S at 10W output varies 18 dB with respect to
>> frequency.
>
> Again, the power amp is not engaged and you're running on the driver. But that
> much variation also implies a problem. Have you sent the rig back to Elecraft?

Just four times. (Actually, three times and I changed the HPA once.)
>
>> Furthermore, my K3S on 10, 17, 20, 30 and 40-meters has higher IMD at 20W
>> than at 100W.
>
> Interesting.

Yep. Which is why I state that I can't with reasonable confidence measure
KPA500 IMD.

Wes N7WS

>
> 73, Jim
>>
>> Wes N7WS
>>
>> On 5/24/2018 8:17 PM, Jim Brown wrote:
>>> On 5/24/2018 7:30 PM, Wes Stewart wrote:
>>>> I haven't measured IMD on my KPA500 either since I don't own two generators
>>>> that are clean enough with the necessary power to do so.
>>>
>>> I evaluate IMD by looking at keying sidebands of a long series of dits, as I
>>> posted hear yesterday. Details of the measurement setup and method, and
>>> lots of results, are here. http://k9yc.com/P3_Spectrum_Measurements.pdf
>>>
>>> It's well known that IMD in the K3/K3S increases at rated output, and is a
>>> lot lower at the levels needed to drive a power amp. It takes 25-30W to
>>> drive the KPA500 to full power, and about twice that to drive my Ten Tec
>>> Titans. The K3/K3S is pretty clean at these levels. The plots for the two
>>> amps look almost exactly the same, and have the same shape as the K3 at
>>> those drive levels.In other words, neither amp is increasing bandwidth. Note
>>> that these measurements are of the envelope of peaks, so they are, in
>>> essence, capturing clicks.
>>>
>>> IMD also increases with low DC supply voltage. I've not done any disciplined
>>> measurements to put numbers to it, but K6XX has. His data is in this pdf
>>> slide show. http://k9yc.com/K6XXAmpTalk.pdf
>>>
>>> 73, Jim K9YC
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Jack Brindle-2

Re: Too Much Power

In reply to this post by Jack Brindle-2

Let me correct myself before others do. Its a 12db difference. And I will rib Bill about it. Still, to the west and north he has very high hills/mountains that block the RF path. Makes me wonder if he was using reverse path for the QSOs.

73,
Jack, W6FB

> On May 25, 2018, at 4:32 PM, Jack Brindle <[hidden email]> wrote:
>
> I’ve seen Bill’s setup. 50 watts with a decent gain antenna (i.e. beam) is equivalent to 800 watts with Bill’s antenna and QTH. He really has done an outstanding job with the resources he has to work with.
> Also remember, we are talking about a 4 to 5 db difference in power here. And when you have pretty large mountains blocking your path to JA and EU, that 4db of power can make a huge difference.
> QTH and the antenna system really make a huge difference!
>
> 73,
> Jack, W6FB
>
>
>> On May 25, 2018, at 4:15 PM, Richard <[hidden email]> wrote:
>>
>> “I have a couple of FT8 contacts in my log -- with a DU and a JA -- reporting me at -24 dB where I WAS OPERATING AT 800 WATTS. YMMV.”
>>
>> Why do you think you need 800 watts in a weak signal mode? Do you have any idea what that does to other operators? I’ve made several 10,000+ mile contacts with 50 watts, as have others who are following the “rules.”
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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>
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Joseph Reed-2

Re: Too Much Power

In reply to this post by Richard-6

I agree it is a weak signal mode. Years ago I used to set up the KX3 at 5 watts and VPN back to my home network from the hotel and operated JT65 and JT9 remotely quite successfully. Unfortunately the advent of FT-8 has introduced a large number of individuals not brought up in the tradition of using low power to communicate on a weak signal mode. The reality is the introduction of those who run high power has changed the weak signal FT-8 ecosphere, and for the worse. Sadly high power has become the new normal.

On the bright side last night I worked ZL4TT from EN63 (8395 miles) and OK2ZU (4524 miles) using an abusive 15 watts from the KX3 and a Butternut HF-9V vertical.

Joe N9JR

> On May 25, 2018, at 6:15 PM, Richard <[hidden email]> wrote:
>
> “I have a couple of FT8 contacts in my log -- with a DU and a JA -- reporting me at -24 dB where I WAS OPERATING AT 800 WATTS. YMMV.”
>
> Why do you think you need 800 watts in a weak signal mode? Do you have any idea what that does to other operators? I’ve made several 10,000+ mile contacts with 50 watts, as have others who are following the “rules.”
> ______________________________________________________________
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Joe Subich, W4TV-4

Re: Too Much Power

On 2018-05-26 2:11 PM, Joseph Reed wrote:
> I agree it is a weak signal mode.

...

> Unfortunately the advent of FT-8 has introduced a large number of
> individuals not brought up in the tradition of using low power to
> communicate on a weak signal mode.

*WHEN* will people get it through their heads that WEAK SIGNAL is
not the same as low power? The original "weak signal" mode is EME
yet almost 100% of EME work is done with high power - 1500 W on
CW and often 1000 W (or more) even with JT65 - plus extremely high
gain antennas (well in excess of the largest "stacked arrays" on HF).

*THERE IS NO "TRADITION" OF LOW POWER FOR WEAK SIGNAL MODES*

Conflating weak signal and low power is an artifact of PSK31/63/125
HF operation where lids run a 2 - 3 KHz wide passband or SDR rigs with
no RF/IF filters and then complain when strong, adjacent signals
overdrive their (cheap) sound cards or drive the IF/mixer/ADC of their
cheaply designed transceiver into distortion or overflow.

Use the same techniques that have been used for decades with *WEAK*
*SIGNAL* modes - narrow IF filters, strong preamplifiers, IF chains
with high compression levels, mixers with high IMD thresholds, etc.
- and there is no conflict between high transmit power and weak
signal modes.

73,

... Joe, W4TV

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Carl Yaffey

Re: Too Much Power

Thank you!!!!!

> On May 26, 2018, at 2:42 PM, Joe Subich, W4TV <[hidden email]> wrote:
>
>
> *WHEN* will people get it through their heads that WEAK SIGNAL is
> not the same as low power?

Carl Yaffey K8NU
Recording studio.
[hidden email]
614 268 6353, Columbus OH
http://www.carl-yaffey.com
http://www.grassahol.com
http://www.bluesswing.com

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Jeff Griffin

Re: Too Much Power

In reply to this post by Jack Brindle-2

Also he did say that the JA gave him a -24 signal report. That doesn't sound like he's melting anybody's receive antennas with the 800 watts :-)

73 Jeff kb2m

-----Original Message-----
From: [hidden email] [mailto:[hidden email]] On Behalf Of Jack Brindle
Sent: Friday, May 25, 2018 7:32 PM
To: Richard
Cc: Elecraft Reflector
Subject: Re: [Elecraft] Too Much Power

I’ve seen Bill’s setup. 50 watts with a decent gain antenna (i.e. beam) is equivalent to 800 watts with Bill’s antenna and QTH. He really has done an outstanding job with the resources he has to work with.
Also remember, we are talking about a 4 to 5 db difference in power here. And when you have pretty large mountains blocking your path to JA and EU, that 4db of power can make a huge difference.
QTH and the antenna system really make a huge difference!

73,
Jack, W6FB

> On May 25, 2018, at 4:15 PM, Richard <[hidden email]> wrote:
>
> “I have a couple of FT8 contacts in my log -- with a DU and a JA -- reporting me at -24 dB where I WAS OPERATING AT 800 WATTS. YMMV.”
>
> Why do you think you need 800 watts in a weak signal mode? Do you have any idea what that does to other operators? I’ve made several 10,000+ mile contacts with 50 watts, as have others who are following the “rules.”

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Eric Swartz - WA6HHQ

Re: Too Much Power

Administrator

In reply to this post by Carl Yaffey

Folks - Thread closed is the interest of avoiding email overload for other list readers.

Also, in the interest of keeping the list signal to noise level reasonable, please take personal operating arguments to other venues.

73,

Eric
Moderator etc.
elecraft.com
_..._

> On May 26, 2018, at 11:44 AM, Carl Yaffey <[hidden email]> wrote:
>
> Thank you!!!!!
>
>> On May 26, 2018, at 2:42 PM, Joe Subich, W4TV <[hidden email]> wrote:
>>
>>
>> *WHEN* will people get it through their heads that WEAK SIGNAL is
>> not the same as low power?
>
> Carl Yaffey K8NU
> Recording studio.
> [hidden email]
> 614 268 6353, Columbus OH
> http://www.carl-yaffey.com
> http://www.grassahol.com
> http://www.bluesswing.com
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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Richard-6

Re: Too Much Power

In reply to this post by Joseph Reed-2

> The reality is the introduction of those who run high power has changed the weak signal FT-8 ecosphere, and for the worse. Sadly high power has become the new normal.

Yes, very sad. Either they don’t realize or don’t care that their huge splattering signals make it difficult and unpleasant for those who are trying to be true to Joe Taylor’s vision.

> On the bright side last night I worked ZL4TT from EN63 (8395 miles) and OK2ZU (4524 miles) using an abusive 15 watts from the KX3 and a Butternut HF-9V vertical.

> Joe N9JR

Outstanding! Those are the moments that are made possible with skill, patience, and perseverance, not just fat checkbooks. A few nights ago, with my hex beam literally on the ground (for adjustments), I worked India on 20 meter FT8 using 50 watts. I jumped for joy when that guy came back through the “pileup” to my call! 8720 miles! My report wasn’t stellar, but who cares?

Unless the FCC imposes power restrictions on FT8 and other weak signal modes, it will just get worse and become a battle of bludgeoning titans. I see no end to it, alas. Somehow, it reminds me of the poem “Ozymandias.”

Richard — W4KBX

>
>
>> On May 25, 2018, at 6:15 PM, Richard <[hidden email]> wrote:
>>
>> “I have a couple of FT8 contacts in my log -- with a DU and a JA -- reporting me at -24 dB where I WAS OPERATING AT 800 WATTS. YMMV.”
>>
>> Why do you think you need 800 watts in a weak signal mode? Do you have any idea what that does to other operators? I’ve made several 10,000+ mile contacts with 50 watts, as have others who are following the “rules.”
>> ______________________________________________________________
>> Elecraft mailing list
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>