Re: [Elecraft] KX1 Power Output

[Don Wilhelm]

Lee,

That is better, but I normally expect 3.5 watts with a true 13.8 volt 
input.  Measure the voltage at the KX1 end (remove the insulating handle 
from the power cord to gain access).  Then try a TUNE and measure the 
voltage again.  If it drops substantially, check the connections at the 
power source to be sure they are tight.  I normally recommend using #18 
wire or larger to reduce the voltage drop.


You did not mention the wattmeter that you were using.  Many analog 
wattmeters are only accurate to 20% of the full scale reading - that 
means if using a 20 watt scale, the reading could be incorrect by as 
much as 4 watts at any point on the scale, making them not reliable for 
low power work.  It is more accurate to connect a god 50 ohm dummy load 
and measure the RF voltage across that load and 'do the math' to figure 
the power output.  There are a few accurate wattmeters available, and 
most of them are digital - the Elecraft WM1, W2, or the Telepost LP-100 
and LP-200 are ones I know I can trust.


You may be able to move the 40/20 power output relationship by changing 
the spacing on the turns of L1 and L2.  Try spreading the turns as well 
as squeezing them.  The most important factor when spreading or 
squeezing the turns is the spacing between the wires at the ends of the 
winding - spreading or squeezing the middle of the winding will not do much.


73,
Don W3FPR

On 6/17/2015 4:08 PM, M L Hooper wrote:

Don,

I installed the .1 microfarad capacitor at C30, but this didn’t change the 
output.

After testing the C30 fix, I subsequently changed R30 to 33 ohms and R11 to 4.7 
ohms.  This did change things, but did not entirely resolve the problem.

At 13.8V input, my power meter shows 3.0 watts on both 20M and 40M.
When I lower the input voltage to 9.0 volts, the meter shows 1.4 watts on 40M 
and 1.7 watts on 20M.
I guess this is within or nearly within specs, but it’s odd that there is more 
output on 20M than on 40M.

Anything else I should try, or should I just use it like this for a while?

Thanks again,

Lee
KG5VU



On Jun 17, 2015, at 1:02 PM, Don Wilhelm  wrote:

Lee,

Yes, I would change that capacitor - there is a chance that it will increase 
the output of the DDS and solve your power output problem.
There is a difference in some KX1s due to care during construction, component 
tolerances, and a host of other factors.
Make certain you counted the toroid turns correctly - a straight wire through 
the core is one turn, a full wrap around the core is 2 turns.
Count the turns that go through the core center.

If all else fails, you can install the KX1 power mod.  If you have a good stock 
of 1/4 watt resistors you may not need to order the kit. Change R11 to 4.7 ohms 
and R30 to 33 ohms.

If those steps do not solve the power output situation, send me an off-list 
email and we can make comparison measurements with my KX1.

The KX1 audio is not 'earbusting', but is normally adequate.  Yes, you may want 
to try headphones or earbuds with a higher SPL rating.

The "Quick Reference" is the only place in the KX1 manual where SLO, SHI, and 
CAL are mentioned - I guess someone overlooked updating that portion of the manual since 
the VERY early days of the KX1. Look at the listing of menu items on page 65 and you will 
see DDS, BFO, and SIG to make those settings.
This has been true since firmware rev 1.01.  1.02 is the latest version.

73,
Don W3FPR

On 6/17/2015 10:58 AM, KG5VU wrote:

Hi,

I just finished building KX1 Serial Number 2879 which is the standard
20M/40M version.  It's a great little rig but, I have a few issues, one
major and two minor:

A)  On final testing I only had about 2.5W on 20M and 2.0W on 40M with power
supply at 13.8V.  I tried to compress the winding on L2, as suggested, but
this only degraded the output slightly (2.2W on 20M and 1.8W on 40M).
Checked the components on the board against the schematic and everything
checked out OK.  Any ideas on what else I should try?  Any idea what RF
voltage levels I should see at each stage?  (I have several decent
oscilloscopes for testing if need be.)

B) The receiver is sensitive (I can hear 0.1 microvolt RF signal on 20 & 40)
but the audio level (particularly for weak signals) is pretty low unless I
advance the AF Gain control to full clockwise.  Is this normal?  Do I just
need to experiment with different sets of ear-buds?

C) The firmware on my KX1 is version 1.02.  The Menu on my unit is different
than the Manual.  It does not include SLO, SHI or CAL.  Instead there are
SIG, DDS and BFO.  Are support documents for revised version available?

For background, I had no difficulty during assembly.  The KX1 passed all
tests except the transmit power output.

I did make one mistake during assembly however.  I mistakenly inserted a .1
microfarad capacitor at C30 instead of a .01 microfarad capacitor.  Since
everything seemed to be working, so I have not corrected this issue.  Think
this could be significant?



___

Re: [Elecraft] KX1 Power Output

[KG5VU]

Correct, Thanks


> On Jun 17, 2015, at 3:23 PM, ke9uw [via Elecraft] 
>  wrote:
> 
> You mean a .01 uF?
> 
> Sent from my iPhone
> Chuck (Jack)
> 
> On Jun 17, 2015, at 3:09 PM, KG5VU [via Elecraft] <[hidden email] 
> > wrote:
> 
>> Don, 
>> 
>> I installed the .1 microfarad capacitor at C30, but this didn’t change the 
>> output. 
>> 
>> After testing the C30 fix, I subsequently changed R30 to 33 ohms and R11 to 
>> 4.7 ohms.  This did change things, but did not entirely resolve the problem. 
>> 
>> At 13.8V input, my power meter shows 3.0 watts on both 20M and 40M.   
>> When I lower the input voltage to 9.0 volts, the meter shows 1.4 watts on 
>> 40M and 1.7 watts on 20M.   
>> I guess this is within or nearly within specs, but it’s odd that there is 
>> more output on 20M than on 40M. 
>> 
>> Anything else I should try, or should I just use it like this for a while? 
>> 
>> Thanks again, 
>> 
>> Lee 
>> KG5VU 
>> 
>> 
>> > On Jun 17, 2015, at 1:02 PM, Don Wilhelm <[hidden email] 
>> > > wrote: 
>> > 
>> > Lee, 
>> > 
>> > Yes, I would change that capacitor - there is a chance that it will 
>> > increase the output of the DDS and solve your power output problem. 
>> > There is a difference in some KX1s due to care during construction, 
>> > component tolerances, and a host of other factors. 
>> > Make certain you counted the toroid turns correctly - a straight wire 
>> > through the core is one turn, a full wrap around the core is 2 turns. 
>> > Count the turns that go through the core center. 
>> > 
>> > If all else fails, you can install the KX1 power mod.  If you have a good 
>> > stock of 1/4 watt resistors you may not need to order the kit. Change R11 
>> > to 4.7 ohms and R30 to 33 ohms. 
>> > 
>> > If those steps do not solve the power output situation, send me an 
>> > off-list email and we can make comparison measurements with my KX1. 
>> > 
>> > The KX1 audio is not 'earbusting', but is normally adequate.  Yes, you may 
>> > want to try headphones or earbuds with a higher SPL rating. 
>> > 
>> > The "Quick Reference" is the only place in the KX1 manual where SLO, SHI, 
>> > and CAL are mentioned - I guess someone overlooked updating that portion 
>> > of the manual since the VERY early days of the KX1. Look at the listing of 
>> > menu items on page 65 and you will see DDS, BFO, and SIG to make those 
>> > settings. 
>> > This has been true since firmware rev 1.01.  1.02 is the latest version. 
>> > 
>> > 73, 
>> > Don W3FPR 
>> > 
>> > On 6/17/2015 10:58 AM, KG5VU wrote: 
>> >> Hi, 
>> >> 
>> >> I just finished building KX1 Serial Number 2879 which is the standard 
>> >> 20M/40M version.  It's a great little rig but, I have a few issues, one 
>> >> major and two minor: 
>> >> 
>> >> A)  On final testing I only had about 2.5W on 20M and 2.0W on 40M with 
>> >> power 
>> >> supply at 13.8V.  I tried to compress the winding on L2, as suggested, 
>> >> but 
>> >> this only degraded the output slightly (2.2W on 20M and 1.8W on 40M). 
>> >> Checked the components on the board against the schematic and everything 
>> >> checked out OK.  Any ideas on what else I should try?  Any idea what RF 
>> >> voltage levels I should see at each stage?  (I have several decent 
>> >> oscilloscopes for testing if need be.) 
>> >> 
>> >> B) The receiver is sensitive (I can hear 0.1 microvolt RF signal on 20 & 
>> >> 40) 
>> >> but the audio level (particularly for weak signals) is pretty low unless 
>> >> I 
>> >> advance the AF Gain control to full clockwise.  Is this normal?  Do I 
>> >> just 
>> >> need to experiment with different sets of ear-buds? 
>> >> 
>> >> C) The firmware on my KX1 is version 1.02.  The Menu on my unit is 
>> >> different 
>> >> than the Manual.  It does not include SLO, SHI or CAL.  Instead there are 
>> >> SIG, DDS and BFO.  Are support documents for revised version available? 
>> >> 
>> >> For background, I had no difficulty during assembly.  The KX1 passed all 
>> >> tests except the transmit power output. 
>> >> 
>> >> I did make one mistake during assembly however.  I mistakenly inserted a 
>> >> .1 
>> >> microfarad capacitor at C30 instead of a .01 microfarad capacitor.  Since 
>> >> everything seemed to be working, so I have not corrected this issue.  
>> >> Think 
>> >> this could be significant? 
>> >> 
>> >> 
>> >
>> 
>> __ 
>> Elecraft mailing list 
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft 
>> 
>> Help: http://mailman.qth.net/mmfaq.htm 
>> 

Re: [Elecraft] KX1 Power Output

[ke9uw]

You mean a .01 uF?

Sent from my iPhone
Chuck (Jack)

On Jun 17, 2015, at 3:09 PM, KG5VU [via Elecraft] 
mailto:ml-node+s365791n7604071...@n2.nabble.com>>
 wrote:

Don,

I installed the .1 microfarad capacitor at C30, but this didn’t change the 
output.

After testing the C30 fix, I subsequently changed R30 to 33 ohms and R11 to 4.7 
ohms.  This did change things, but did not entirely resolve the problem.

At 13.8V input, my power meter shows 3.0 watts on both 20M and 40M.
When I lower the input voltage to 9.0 volts, the meter shows 1.4 watts on 40M 
and 1.7 watts on 20M.
I guess this is within or nearly within specs, but it’s odd that there is more 
output on 20M than on 40M.

Anything else I should try, or should I just use it like this for a while?

Thanks again,

Lee
KG5VU


> On Jun 17, 2015, at 1:02 PM, Don Wilhelm <[hidden 
> email]> wrote:
>
> Lee,
>
> Yes, I would change that capacitor - there is a chance that it will increase 
> the output of the DDS and solve your power output problem.
> There is a difference in some KX1s due to care during construction, component 
> tolerances, and a host of other factors.
> Make certain you counted the toroid turns correctly - a straight wire through 
> the core is one turn, a full wrap around the core is 2 turns.
> Count the turns that go through the core center.
>
> If all else fails, you can install the KX1 power mod.  If you have a good 
> stock of 1/4 watt resistors you may not need to order the kit. Change R11 to 
> 4.7 ohms and R30 to 33 ohms.
>
> If those steps do not solve the power output situation, send me an off-list 
> email and we can make comparison measurements with my KX1.
>
> The KX1 audio is not 'earbusting', but is normally adequate.  Yes, you may 
> want to try headphones or earbuds with a higher SPL rating.
>
> The "Quick Reference" is the only place in the KX1 manual where SLO, SHI, and 
> CAL are mentioned - I guess someone overlooked updating that portion of the 
> manual since the VERY early days of the KX1. Look at the listing of menu 
> items on page 65 and you will see DDS, BFO, and SIG to make those settings.
> This has been true since firmware rev 1.01.  1.02 is the latest version.
>
> 73,
> Don W3FPR
>
> On 6/17/2015 10:58 AM, KG5VU wrote:
>> Hi,
>>
>> I just finished building KX1 Serial Number 2879 which is the standard
>> 20M/40M version.  It's a great little rig but, I have a few issues, one
>> major and two minor:
>>
>> A)  On final testing I only had about 2.5W on 20M and 2.0W on 40M with power
>> supply at 13.8V.  I tried to compress the winding on L2, as suggested, but
>> this only degraded the output slightly (2.2W on 20M and 1.8W on 40M).
>> Checked the components on the board against the schematic and everything
>> checked out OK.  Any ideas on what else I should try?  Any idea what RF
>> voltage levels I should see at each stage?  (I have several decent
>> oscilloscopes for testing if need be.)
>>
>> B) The receiver is sensitive (I can hear 0.1 microvolt RF signal on 20 & 40)
>> but the audio level (particularly for weak signals) is pretty low unless I
>> advance the AF Gain control to full clockwise.  Is this normal?  Do I just
>> need to experiment with different sets of ear-buds?
>>
>> C) The firmware on my KX1 is version 1.02.  The Menu on my unit is different
>> than the Manual.  It does not include SLO, SHI or CAL.  Instead there are
>> SIG, DDS and BFO.  Are support documents for revised version available?
>>
>> For background, I had no difficulty during assembly.  The KX1 passed all
>> tests except the transmit power output.
>>
>> I did make one mistake during assembly however.  I mistakenly inserted a .1
>> microfarad capacitor at C30 instead of a .01 microfarad capacitor.  Since
>> everything seemed to be working, so I have not corrected this issue.  Think
>> this could be significant?
>>
>>
>

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Re: [Elecraft] KX1 Power Output

[M L Hooper]

Don,

I installed the .1 microfarad capacitor at C30, but this didn’t change the 
output.

After testing the C30 fix, I subsequently changed R30 to 33 ohms and R11 to 4.7 
ohms.  This did change things, but did not entirely resolve the problem.

At 13.8V input, my power meter shows 3.0 watts on both 20M and 40M.  
When I lower the input voltage to 9.0 volts, the meter shows 1.4 watts on 40M 
and 1.7 watts on 20M.  
I guess this is within or nearly within specs, but it’s odd that there is more 
output on 20M than on 40M.

Anything else I should try, or should I just use it like this for a while?

Thanks again,

Lee
KG5VU


> On Jun 17, 2015, at 1:02 PM, Don Wilhelm  wrote:
> 
> Lee,
> 
> Yes, I would change that capacitor - there is a chance that it will increase 
> the output of the DDS and solve your power output problem.
> There is a difference in some KX1s due to care during construction, component 
> tolerances, and a host of other factors.
> Make certain you counted the toroid turns correctly - a straight wire through 
> the core is one turn, a full wrap around the core is 2 turns.
> Count the turns that go through the core center.
> 
> If all else fails, you can install the KX1 power mod.  If you have a good 
> stock of 1/4 watt resistors you may not need to order the kit. Change R11 to 
> 4.7 ohms and R30 to 33 ohms.
> 
> If those steps do not solve the power output situation, send me an off-list 
> email and we can make comparison measurements with my KX1.
> 
> The KX1 audio is not 'earbusting', but is normally adequate.  Yes, you may 
> want to try headphones or earbuds with a higher SPL rating.
> 
> The "Quick Reference" is the only place in the KX1 manual where SLO, SHI, and 
> CAL are mentioned - I guess someone overlooked updating that portion of the 
> manual since the VERY early days of the KX1. Look at the listing of menu 
> items on page 65 and you will see DDS, BFO, and SIG to make those settings.
> This has been true since firmware rev 1.01.  1.02 is the latest version.
> 
> 73,
> Don W3FPR
> 
> On 6/17/2015 10:58 AM, KG5VU wrote:
>> Hi,
>> 
>> I just finished building KX1 Serial Number 2879 which is the standard
>> 20M/40M version.  It's a great little rig but, I have a few issues, one
>> major and two minor:
>> 
>> A)  On final testing I only had about 2.5W on 20M and 2.0W on 40M with power
>> supply at 13.8V.  I tried to compress the winding on L2, as suggested, but
>> this only degraded the output slightly (2.2W on 20M and 1.8W on 40M).
>> Checked the components on the board against the schematic and everything
>> checked out OK.  Any ideas on what else I should try?  Any idea what RF
>> voltage levels I should see at each stage?  (I have several decent
>> oscilloscopes for testing if need be.)
>> 
>> B) The receiver is sensitive (I can hear 0.1 microvolt RF signal on 20 & 40)
>> but the audio level (particularly for weak signals) is pretty low unless I
>> advance the AF Gain control to full clockwise.  Is this normal?  Do I just
>> need to experiment with different sets of ear-buds?
>> 
>> C) The firmware on my KX1 is version 1.02.  The Menu on my unit is different
>> than the Manual.  It does not include SLO, SHI or CAL.  Instead there are
>> SIG, DDS and BFO.  Are support documents for revised version available?
>> 
>> For background, I had no difficulty during assembly.  The KX1 passed all
>> tests except the transmit power output.
>> 
>> I did make one mistake during assembly however.  I mistakenly inserted a .1
>> microfarad capacitor at C30 instead of a .01 microfarad capacitor.  Since
>> everything seemed to be working, so I have not corrected this issue.  Think
>> this could be significant?
>> 
>> 
> 

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Re: [Elecraft] KX1 Power Output

[Don Wilhelm]

Lee,

Yes, I would change that capacitor - there is a chance that it will 
increase the output of the DDS and solve your power output problem.
There is a difference in some KX1s due to care during construction, 
component tolerances, and a host of other factors.
Make certain you counted the toroid turns correctly - a straight wire 
through the core is one turn, a full wrap around the core is 2 turns.

Count the turns that go through the core center.

If all else fails, you can install the KX1 power mod.  If you have a 
good stock of 1/4 watt resistors you may not need to order the kit. 
Change R11 to 4.7 ohms and R30 to 33 ohms.


If those steps do not solve the power output situation, send me an 
off-list email and we can make comparison measurements with my KX1.


The KX1 audio is not 'earbusting', but is normally adequate.  Yes, you 
may want to try headphones or earbuds with a higher SPL rating.


The "Quick Reference" is the only place in the KX1 manual where SLO, 
SHI, and CAL are mentioned - I guess someone overlooked updating that 
portion of the manual since the VERY early days of the KX1. Look at the 
listing of menu items on page 65 and you will see DDS, BFO, and SIG to 
make those settings.

This has been true since firmware rev 1.01.  1.02 is the latest version.

73,
Don W3FPR

On 6/17/2015 10:58 AM, KG5VU wrote:

Hi,

I just finished building KX1 Serial Number 2879 which is the standard
20M/40M version.  It's a great little rig but, I have a few issues, one
major and two minor:

A)  On final testing I only had about 2.5W on 20M and 2.0W on 40M with power
supply at 13.8V.  I tried to compress the winding on L2, as suggested, but
this only degraded the output slightly (2.2W on 20M and 1.8W on 40M).
Checked the components on the board against the schematic and everything
checked out OK.  Any ideas on what else I should try?  Any idea what RF
voltage levels I should see at each stage?  (I have several decent
oscilloscopes for testing if need be.)

B) The receiver is sensitive (I can hear 0.1 microvolt RF signal on 20 & 40)
but the audio level (particularly for weak signals) is pretty low unless I
advance the AF Gain control to full clockwise.  Is this normal?  Do I just
need to experiment with different sets of ear-buds?

C) The firmware on my KX1 is version 1.02.  The Menu on my unit is different
than the Manual.  It does not include SLO, SHI or CAL.  Instead there are
SIG, DDS and BFO.  Are support documents for revised version available?

For background, I had no difficulty during assembly.  The KX1 passed all
tests except the transmit power output.

I did make one mistake during assembly however.  I mistakenly inserted a .1
microfarad capacitor at C30 instead of a .01 microfarad capacitor.  Since
everything seemed to be working, so I have not corrected this issue.  Think
this could be significant?




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Re: [Elecraft] KX1 Power Output

[KG5VU]

Phil,

Fortunately, I had a spare .1 microfarad capacitor on hand.  Not exactly the
same size but very close.

Thanks,
Lee



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Re: [Elecraft] KX1 Power Output

[Phil Hystad]

> I did make one mistake during assembly however.  I mistakenly inserted a .1
> microfarad capacitor at C30 instead of a .01 microfarad capacitor.  Since
> everything seemed to be working, so I have not corrected this issue.


Wouldn’t that mean you made two mistakes.  Unless of course you had an extra
0.1 mF capacitor.  But, if you have exactly the right amount of parts, which is 
the
usual thing, then all misplaced part mistakes come in pairs.

73, phil, K7PEH



> On Jun 17, 2015, at 7:58 AM, KG5VU  wrote:
> 
> Hi,
> 
> I just finished building KX1 Serial Number 2879 which is the standard
> 20M/40M version.  It's a great little rig but, I have a few issues, one
> major and two minor:
> 
> A)  On final testing I only had about 2.5W on 20M and 2.0W on 40M with power
> supply at 13.8V.  I tried to compress the winding on L2, as suggested, but
> this only degraded the output slightly (2.2W on 20M and 1.8W on 40M). 
> Checked the components on the board against the schematic and everything
> checked out OK.  Any ideas on what else I should try?  Any idea what RF
> voltage levels I should see at each stage?  (I have several decent
> oscilloscopes for testing if need be.)
> 
> B) The receiver is sensitive (I can hear 0.1 microvolt RF signal on 20 & 40)
> but the audio level (particularly for weak signals) is pretty low unless I
> advance the AF Gain control to full clockwise.  Is this normal?  Do I just
> need to experiment with different sets of ear-buds?
> 
> C) The firmware on my KX1 is version 1.02.  The Menu on my unit is different
> than the Manual.  It does not include SLO, SHI or CAL.  Instead there are
> SIG, DDS and BFO.  Are support documents for revised version available?
> 
> For background, I had no difficulty during assembly.  The KX1 passed all
> tests except the transmit power output.  
> 
> I did make one mistake during assembly however.  I mistakenly inserted a .1
> microfarad capacitor at C30 instead of a .01 microfarad capacitor.  Since
> everything seemed to be working, so I have not corrected this issue.  Think
> this could be significant?
> 
> Thanks for any assistance you can provide.
> 
> Lee
> KG5VU
> 
> 
> 
> 
> 
> 
> 
> --
> View this message in context: 
> http://elecraft.365791.n2.nabble.com/KX1-Power-Output-tp7604063.html
> Sent from the Elecraft mailing list archive at Nabble.com.
> __
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Re: [Elecraft] KX1 Power Output

[Don Wilhelm]

Tom,

Yes, your values look reasonable.  The KX1 will always indicate that the 
voltage is about 0.4 volts lower than read at your supply.  There is a 
series diode to prevent damage from reverse polarity, so the inside of 
the KX1 sees a voltage that is one diode drop less than your supply.

73,
Don W3FPR

On 1/30/2012 9:44 PM, Tom Crites wrote:
> I hope you can read this, but do the values look reasonable, for a KX1
> with the output power mod.  Peak to peak (Vpp) voltages and RMS (Vrms)
> were taken with a high end O'scope and used to compute the Power
> values (Ppp and Prms).
>
> Seems the KX1 read the supply voltage about 0.4 volts low.
>
> Thanks,
> Tom Crites, KC8SES
>
>
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Re: [Elecraft] KX1 Power Output

[Don Wilhelm]

Panos,

Great to hear you have the KX1 working.

If you have the correct number of turns on T1 and the red winding is 
spread over most of the core, then T1 is OK - I did not see anything 
wrong with it when it was here.


First try spreading/compressing the turns of L2 to see if the power 
output on 20 increases, then if you still do not have 3 watts on 20 
meters with a 12 volt (or 13.8 volt) power supply, my recommendation is 
to change the resistors for a little more output.


The power supply voltage does make a difference in the power output 
available from the KX1.


73,
Don W3FPR

Panos wrote:

Hi all

 


KX1 sn #01859 completed and everything (except some unexpected birdies
inside the band) seems

Ok (receiver is fantastic IMO).

 


Power output on 7.100 Mhz is a hair less 3W and on 14.100 Mhz is 2.1-2.2 W

 


According to your experience out there what is best? :

 


a.  Take out the T1 transformer and try to rewind and reinstall it?
b.  OR change the R11 and R30 to their PowerMod values?


  

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RE: [Elecraft] KX1 power output increase -- free mod kit available

[Ron D'Eau Claire]

You are absolutely right. It is R4, not R30! 

Ron 

-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Randy Rathbun NV0U
Sent: Wednesday, April 05, 2006 5:24 PM
To: wayne burdick
Cc: Elecraft Reflector
Subject: Re: [Elecraft] KX1 power output increase -- free mod kit available


-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1

I have not opened mine up yet, but in looking at this I found a typo  
in the App Note

it says "Locate resistor R30 on the bottom of the board between  
trimmer pot R30" should that be R4?

Randy Rathbun NV0U
[EMAIL PROTECTED]
K2#1981, kx1 #1318, ARS #895, QRPARCI #10776, FP#1292, KCQRP #1


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Re: [Elecraft] KX1 power output increase -- free mod kit available

[Randy Rathbun NV0U]

-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1

I have not opened mine up yet, but in looking at this I found a typo  
in the App Note


it says "Locate resistor R30 on the bottom of the board between  
trimmer pot R30" should that be R4?


Randy Rathbun NV0U
[EMAIL PROTECTED]
K2#1981, kx1 #1318, ARS #895, QRPARCI #10776, FP#1292, KCQRP #1



On Apr 5, 2006, at 6:07PM, wayne burdick wrote:

Some KX1s have slightly lower transmitter output than others. When  
using a 14V supply, the output may be as low as 2.5 to 3 watts  
across all bands instead of the expected 3 to 4 watts. When using  
the internal battery the output maybe as low as 0.75 to 1 watt  
instead of he expected 1 to 1.5 watts.


Some builders have noticed this effect only after installing the  
KXB3080 option (30/80 meter module). The low-pass filter module  
supplied with the KXB3080 has slightly different characteristics  
from the original, which is necessary to obtain coverage of all  
four bands.


If you think your KX1's output is on the low side, for whatever  
reason, you can order our model #KX1PWRMODKT at no charge. It's  
listed at the bottom of our Parts and Mod Kits page:


   http://www.elecraft.com/order_form_parts.htm

The mod kit provides two resistors and instructions, and the change  
is easy to make. If you have your own stash of resistors, you can  
just download the application note at:


   http://www.elecraft.com/manual/E740099%20KX1%20Application%20Note 
%20Rev%20A.pdf


NOTE: We don't recommend making the change if your KX1 already puts  
out 4 watts or more on some bands. While it's generally safe to  
operate the KX1 at 5 watts, the design was optimized at the 4-watt  
level to provide plenty of safety margin in terms of RFI, current  
drain, and heat sinking via the top cover.


73,
Wayne
N6KR


---

http://www.elecraft.com

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RE: [Elecraft] KX1 power output increase -- free mod kit available

[Ron D'Eau Claire]

Since someone already hollered privately and said, "That URL doesn't work!" 

Note that most people will have to splice it together again! The long URL
gets broken in a lot of e-mail readers. 

An alternative "TinyURL" that will take you to the same Elecraft document to
download/view the Application Note is:

http://tinyurl.com/rzp42


Ron AC7AC

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