Elecraft

Calibration of KXV3 module

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K2QI

Calibration of KXV3 module

Dear group,

Page 50 of the user manual states that a 50 ohm resistor should be attached to the XVTR OUT jack for calibration. If I don’t have a resistor, can I use a 50 ohm BNC stubby HT antenna instead since output is only 1 mW?

73,

James KC2UEE

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Mark Bayern

Re: Calibration of KXV3 module

Will the stubby helical whip really be 50ohms at the freq out from the
XVTR OUT jack? Are you willing to bet your calibration on it?

Mark AD5SS

On Wed, Feb 11, 2009 at 3:26 PM, James Sarte <[hidden email]> wrote:

> Dear group,
>
>
>
> Page 50 of the user manual states that a 50 ohm resistor should be attached
> to the XVTR OUT jack for calibration. If I don't have a resistor, can I use
> a 50 ohm BNC stubby HT antenna instead since output is only 1 mW?
>
>
>
> 73,
>
> James KC2UEE

K2QI

Re: Calibration of KXV3 module

In reply to this post by K2QI

Re: [Elecraft] Calibration of KXV3 module

Hi Stephen,

Yes, I’m familiar with 50 ohm BNC network terminators. This will work without issue and get me properly calibrated? Otherwise, I can always get an SO239 to BNC adapter and run a cable into my 300w 50 ohm dummy load.

73,

James KC2UEE

From: Stephen Prior [mailto:[hidden email]]
Sent: Wednesday, February 11, 2009 5:05 PM
To: James Sarte
Subject: Re: [Elecraft] Calibration of KXV3 module

James,

It will only (possibly) be 50 ohms at the frequency for which the stubby antenna is designed, which will almost certainly not be the frequency coming out of the XVTR jack, so it won’t work. I expect a 47 ohm resistor would be close enough, but ideal for this purpose would be a 50 ohm BNC termination that used to be used in pc networking if you are familiar with that. Otherwise a coax cable (via adaptors if necessary) from a good dummy load to the transverter terminal would be fine.

Hope that helps

Stephen G4SJP

On 11/02/2009 21:26, "James Sarte" <kc2uee@...> wrote:

Dear group,

Page 50 of the user manual states that a 50 ohm resistor should be attached to the XVTR OUT jack for calibration. If I don’t have a resistor, can I use a 50 ohm BNC stubby HT antenna instead since output is only 1 mW?

73,
James KC2UEE

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Don Wilhelm-4

Re: Calibration of KXV3 module

In reply to this post by K2QI

James,

The HT antenna is frequency sensitive, so it will not work. A dummy load
will work fine.

73,
Don W3FPR

James Sarte wrote:

>
> Dear group,
>
> Page 50 of the user manual states that a 50 ohm resistor should be
> attached to the XVTR OUT jack for calibration. If I don’t have a
> resistor, can I use a 50 ohm BNC stubby HT antenna instead since
> output is only 1 mW?
>
> 73,
>
> James KC2UEE
>
>

Eric Swartz - WA6HHQ

Re: Calibration of KXV3 module

Administrator

In reply to this post by K2QI

This will not work. The HT antenna is almost guaranteed -not- to be 50 ohms, especially at the nominal 28 MHz output of the xv port.

The only place this antenna will be even close to resonance is at its operating fequency (I'm assumung 144 or 432 MHz). And HT antennas are notoiously variable in their actual impedance, since it usually depends on the interaction with you body when you hold the HT.

You need a 50 ohm resistive termination.

73,

Eric
_..._
-----Original Message-----
From: Mark Bayern <[hidden email]>
Date: Wednesday, Feb 11, 2009 1:49 pm
Subject: Re: [Elecraft] Calibration of KXV3 module
To: James Sarte <[hidden email]>
CC: "[hidden email]" <[hidden email]>

Will the stubby helical whip really be 50ohms at the freq out from the
XVTR OUT jack? Are you willing to bet your calibration on it?

Mark AD5SS

On Wed, Feb 11, 2009 at 3:26 PM, James Sarte <[hidden email]> wrote:
Dear group,

>

> Page 50 of the user manual states that a 50 ohm resistor should be attached
to the XVTR OUT jack for calibration. If I don't have a resistor, can I use
a 50 ohm BNC stubby HT antenna instead since output is only 1 mW?

>

> 73,

> James KC2UEE
______________________________________________________________
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Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

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K2QI

Re: Calibration of KXV3 module

Hi Eric,

Yes, I stand corrected. I will use a 50 ohm dummy load with an SO239 to BNC
adapter when it comes time to calibrate. Also, someone suggested using a 50
ohm terminator plug as used in computer networks. That sounded like a
pretty interesting idea.

73,
James KC2UEE

-----Original Message-----
From: Eric Swartz - WA6HHQ, Elecraft [mailto:[hidden email]]
Sent: Wednesday, February 11, 2009 6:17 PM
To: [hidden email]
Cc: [hidden email]; [hidden email]
Subject: Re: [Elecraft] Calibration of KXV3 module

This will not work. The HT antenna is almost guaranteed -not- to be 50 ohms,
especially at the nominal 28 MHz output of the xv port.

The only place this antenna will be even close to resonance is at its
operating fequency (I'm assumung 144 or 432 MHz). And HT antennas are
notoiously variable in their actual impedance, since it usually depends on
the interaction with you body when you hold the HT.

You need a 50 ohm resistive termination.

73,

Eric
_..._
-----Original Message-----
From: Mark Bayern <[hidden email]>
Date: Wednesday, Feb 11, 2009 1:49 pm
Subject: Re: [Elecraft] Calibration of KXV3 module
To: James Sarte <[hidden email]>
CC: "[hidden email]" <[hidden email]>

Will the stubby helical whip really be 50ohms at the freq out from the
XVTR OUT jack? Are you willing to bet your calibration on it?

Mark AD5SS

On Wed, Feb 11, 2009 at 3:26 PM, James Sarte <[hidden email]> wrote:
Dear group,

>

> Page 50 of the user manual states that a 50 ohm resistor should be
attached
to the XVTR OUT jack for calibration. If I don't have a resistor, can I
use
a 50 ohm BNC stubby HT antenna instead since output is only 1 mW?

>

> 73,

> James KC2UEE
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

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Please help support this email list: http://www.qsl.net/donate.html

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Help: http://mailman.qth.net/mmfaq.htm
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Bruce McLaughlin-2

Re: Calibration of KXV3 module

In reply to this post by K2QI

Re: [Elecraft] Calibration of KXV3 module

If you use a dummy load, you may wish to be certain it's okay for VHF. Some dummy loads which are primarily designed for HF frequencies become rather reactive on VHF. I think the length of the internal leads in the device had some inductance and/or capacitance to the mix and, therefore, below presented to the radio is no longer a pure resistance.

Bruce-W8FU

From: [hidden email] [mailto:[hidden email]] On Behalf Of James Sarte
Sent: Wednesday, February 11, 2009 5:53 PM
To: 'Stephen Prior'
Cc: [hidden email]
Subject: Re: [Elecraft] Calibration of KXV3 module

Hi Stephen,

73,

James KC2UEE

From: Stephen Prior [mailto:[hidden email]]
Sent: Wednesday, February 11, 2009 5:05 PM
To: James Sarte
Subject: Re: [Elecraft] Calibration of KXV3 module

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