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low IF out on K3

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Enrico Lorenzoni IU3AZC

low IF out on K3

hello everyone,
I just compared my k3 with a friend's one and my IF out is much lower
than his k3.
I suspected it when listening on a softrock, but now I can see a
difference like 10 or 20db off.

So I inspected my k3 and the IF out connector is fine. Multimeter says 0
ohms between bnc contacts and P86 pins on motherboard.
What can I check next?
Anyone did fix this same issue?

thanks

Enrico IU4AZC
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Art Hejduk

Re: low IF out on K3

Enrico,

How old is your K3? I believe they made a change to increase the output on
the "newer" units. I'm not sure which serial number this began on, but
mine has the higher output, and it is serial number 43XX.

73,
Art WB8ENE

On Thu, Apr 7, 2016 at 3:55 PM, Enrico Lorenzoni IU3AZC <[hidden email]>
wrote:

> hello everyone,
> I just compared my k3 with a friend's one and my IF out is much lower than
> his k3.
> I suspected it when listening on a softrock, but now I can see a
> difference like 10 or 20db off.
>
> So I inspected my k3 and the IF out connector is fine. Multimeter says 0
> ohms between bnc contacts and P86 pins on motherboard.
> What can I check next?
> Anyone did fix this same issue?
>
> thanks
>
> Enrico IU4AZC
> ______________________________________________________________
> 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
> Message delivered to [hidden email]
>

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Elecraft mailing list
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Enrico Lorenzoni IU3AZC

Re: low IF out on K3

Hello, my K3 is 80xx and my friend's is 38xx

thanks
Enrico

Il 07/04/2016 22:03, Art Hejduk ha scritto:

> Enrico,
>
> How old is your K3? I believe they made a change to increase the
> output on the "newer" units. I'm not sure which serial number this
> began on, but mine has the higher output, and it is serial number 43XX.
>
> 73,
> Art WB8ENE
>
> On Thu, Apr 7, 2016 at 3:55 PM, Enrico Lorenzoni IU3AZC
> <[hidden email] <mailto:[hidden email]>> wrote:
>
> hello everyone,
> I just compared my k3 with a friend's one and my IF out is much
> lower than his k3.
> I suspected it when listening on a softrock, but now I can see a
> difference like 10 or 20db off.
>
> So I inspected my k3 and the IF out connector is fine. Multimeter
> says 0 ohms between bnc contacts and P86 pins on motherboard.
> What can I check next?
> Anyone did fix this same issue?
>
> thanks
>
> Enrico IU4AZC
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
> <mailto:[hidden email]>
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
> <mailto:[hidden email]>
>
>

Enrico Lorenzoni IU3AZC

Re: low IF out on K3

Hi, I confirm: R8 is labeled "133", so it is a 13k resistor.

Enrico

Il 07/04/2016 22:10, Art Hejduk ha scritto:

> Enrico,
>
> Yours should definitely have this change done then. See the attached
> PDF file.
>
> 73,
> Art WB8ENE
>
> On Thu, Apr 7, 2016 at 4:04 PM, Enrico Lorenzoni IU3AZC
> <[hidden email] <mailto:[hidden email]>> wrote:
>
>
> Hello, my K3 is 80xx and my friend's is 38xx
>
> thanks
> Enrico
>
>
> Il 07/04/2016 22:03, Art Hejduk ha scritto:
>> Enrico,
>>
>> How old is your K3? I believe they made a change to increase the
>> output on the "newer" units. I'm not sure which serial number
>> this began on, but mine has the higher output, and it is serial
>> number 43XX.
>>
>> 73,
>> Art WB8ENE
>>
>> On Thu, Apr 7, 2016 at 3:55 PM, Enrico Lorenzoni IU3AZC
>> <[hidden email] <mailto:[hidden email]>> wrote:
>>
>> hello everyone,
>> I just compared my k3 with a friend's one and my IF out is
>> much lower than his k3.
>> I suspected it when listening on a softrock, but now I can
>> see a difference like 10 or 20db off.
>>
>> So I inspected my k3 and the IF out connector is fine.
>> Multimeter says 0 ohms between bnc contacts and P86 pins on
>> motherboard.
>> What can I check next?
>> Anyone did fix this same issue?
>>
>> thanks
>>
>> Enrico IU4AZC
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>> <mailto:[hidden email]>
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list:
>> http://www.qsl.net/donate.html
>> Message delivered to [hidden email]
>> <mailto:[hidden email]>
>>
>>
>
>

Enrico Lorenzoni IU3AZC

Re: low IF out on K3

In reply to this post by Enrico Lorenzoni IU3AZC

hello everyone. My K3 is # 80XX so it should be fine.
With my multimeter I checked R8 and it's reading 270ohms (mounted on the
board).
From the schematic I guess there should be no DC flowing and that I
should read 13.3k, so I think R8 is broken or the problem is in Q10 fet,
being resistive on the gate.
anyone has experience in this, before I start desoldering components and
measure them?

thanks

Enrico

Il 07/04/2016 22:24, Ron D'Eau Claire ha scritto:

> Older K3 transceivers (built before September 2009) do have lower output
> than later units. Elecraft published a modification that involves replacing
> a single resistor to bring up the level.
>
> They have a kit that includes an SMD and a leaded resistor (you can use
> either, only one is installed). Order the KIO3BUFFKT. You can see what is
> involved by reviewing the instructions available for download here:
>
> http://www.elecraft.com/K3/mods/IF_Output_Buffer_Gain_Mod_Rev_A.pdf
>
> If you have a 13K ohm, 1/8 watt leaded resistor or if you'd rather work with
> an SMD, a 13K 0805 size resistor, you won't need the kit.
>
> 73, Ron AC7AC
>
> -----Original Message-----
> From: Elecraft [mailto:[hidden email]] On Behalf Of Enrico
> Lorenzoni IU3AZC
> Sent: Thursday, April 7, 2016 12:55 PM
> To: [hidden email]
> Subject: [Elecraft] low IF out on K3
>
> hello everyone,
> I just compared my k3 with a friend's one and my IF out is much lower than
> his k3.
> I suspected it when listening on a softrock, but now I can see a difference
> like 10 or 20db off.
>
> So I inspected my k3 and the IF out connector is fine. Multimeter says 0
> ohms between bnc contacts and P86 pins on motherboard.
> What can I check next?
> Anyone did fix this same issue?
>
> thanks
>
> Enrico IU4AZC
> ______________________________________________________________
> 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 Message
> delivered to [hidden email]
>