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P3 TX Audio monitoring

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Gary Gregory

P3 TX Audio monitoring

*Well as nobody responded to my original post which identified a possible
issue with my station setup which allowed the P3 to display live TX audio
from the K3 I thought I would mention the subsequent test I tried.

1. Check that both BNC connectors were 'seated correctly'
2. Replace the Elecraft supplied BNC inter-connect cable
3. Relocate the P3 from it's position on the desk.

None of these appears to have resolved the issue..which does not disappoint
me one bit. After all, it IS a desired 'feature' for me.

It appears that if the P3 is placed on the left side and on top of the
KPA-500 there may be some 'leakage' getting into the P3 and showing up on
the P3 display as TX audio. This may be the root cause?

Whilst this does not happen on every transmission, and is not deliberately
repeatable, it does show up several times a day and I think it's rather
cool even if not consistent which would be even nicer.

I know many have asked for this to be a standard feature of the P3 and I
also note that Alan (N1AL) has stated this is not an easy option and I got
the impression it most likely would not be done in the near future...read
years?

For those of us with not so good hearing when it comes to the voice
spectrum, this is a way for us to check on our transmitted signal and not
need to wait for a negative comment or intrude on a QSO and inquire if our
TX audio is OK. Given the lack of operators who would be either unable to
give an accurate description of the audio, or indeed the sometimes abrupt
response received and in many cases the other station has tailored his
receive audio to best suit his/her hearing, I will take advantage of this
anomaly for now and enjoy it.

Thanks for the BW.......:-)

73

Gary
*
--
Gary
VK4FD - Motorhome Mobile
Elecraft Equipment
K3 #679,P3 #1629, KPA-500 #018 KAT-500#??
Living the dream!!!
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Guy, K2AV

Re: P3 TX Audio monitoring

Wouldn't part of displaying the TX signal have to be implemented in the K3?
If so it's a TWO box modification. Fix the K3 to send the TX signal
across the connector to the P3 instead of the RX bandwidth. Then the P3
would need to switch to the bandwidth needed to display the TX signal when
the K3 was in transmit. This last because most of the time we are watching
on the P3 where we are NOT listening with the K3.

Some other way to do that? 73, Guy.

On Tue, Jul 3, 2012 at 9:03 PM, Gary Gregory <[hidden email]> wrote:

> *Well as nobody responded to my original post which identified a possible
> issue with my station setup which allowed the P3 to display live TX audio
> from the K3 I thought I would mention the subsequent test I tried.
>
> 1. Check that both BNC connectors were 'seated correctly'
> 2. Replace the Elecraft supplied BNC inter-connect cable
> 3. Relocate the P3 from it's position on the desk.
>
> None of these appears to have resolved the issue..which does not disappoint
> me one bit. After all, it IS a desired 'feature' for me.
>
> It appears that if the P3 is placed on the left side and on top of the
> KPA-500 there may be some 'leakage' getting into the P3 and showing up on
> the P3 display as TX audio. This may be the root cause?
>
> Whilst this does not happen on every transmission, and is not deliberately
> repeatable, it does show up several times a day and I think it's rather
> cool even if not consistent which would be even nicer.
>
> I know many have asked for this to be a standard feature of the P3 and I
> also note that Alan (N1AL) has stated this is not an easy option and I got
> the impression it most likely would not be done in the near future...read
> years?
>
> For those of us with not so good hearing when it comes to the voice
> spectrum, this is a way for us to check on our transmitted signal and not
> need to wait for a negative comment or intrude on a QSO and inquire if our
> TX audio is OK. Given the lack of operators who would be either unable to
> give an accurate description of the audio, or indeed the sometimes abrupt
> response received and in many cases the other station has tailored his
> receive audio to best suit his/her hearing, I will take advantage of this
> anomaly for now and enjoy it.
>
> Thanks for the BW.......:-)
>
> 73
>
> Gary
> *
> --
> Gary
> VK4FD - Motorhome Mobile
> Elecraft Equipment
> K3 #679,P3 #1629, KPA-500 #018 KAT-500#??
> Living the dream!!!
> ______________________________________________________________
> 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
>

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WB4SON

Re: P3 TX Audio monitoring

Makes you wonder what the IR port on the back of the P3 was planned for (TX
RF Sampler Pickup maybe)?

73, Bob, WB4SON
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73, Bob, WB4SON

Don Wilhelm-4

Re: P3 TX Audio monitoring

In reply to this post by Guy, K2AV

Guy,

That would still only give a picture of the K3 output as found by the IF
leak-through signal. I think a better approach is to wait until the
external sensor is developed and released - that will show the real
signal going out to the antenna.

73,
Don W3FPR

On 7/3/2012 9:55 PM, Guy Olinger K2AV wrote:

> Wouldn't part of displaying the TX signal have to be implemented in the K3?
> If so it's a TWO box modification. Fix the K3 to send the TX signal
> across the connector to the P3 instead of the RX bandwidth. Then the P3
> would need to switch to the bandwidth needed to display the TX signal when
> the K3 was in transmit. This last because most of the time we are watching
> on the P3 where we are NOT listening with the K3.
>
> Some other way to do that? 73, Guy.
>
>

Alan Bloom

Re: P3 TX Audio monitoring

In reply to this post by Gary Gregory

On Wed, 2012-07-04 at 11:03 +1000, Gary Gregory wrote:
> *Well as nobody responded to my original post which identified a possible
> issue with my station setup which allowed the P3 to display live TX audio
> from the K3 ...

I should have copied the list on my previous reply to Gary. (See below)

Alan N1AL

-------- Forwarded Message --------
From: Alan Bloom <[hidden email]>

> Reply-to: [hidden email]
> To: Gary Gregory <[hidden email]>
> Subject: Re: Fwd: Screen Shots showing TX signal appearing on P3
> Date: Mon, 02 Jul 2012 10:07:08 -0700
>
> Hi Gary,
>
> The P3 is supposed to blank the screen whenever the K3 goes into
> transmit mode. If that's not happening then it sounds like there must
> be an RS-232 communications problem between the K3 and P3. One
> possibility is if you have some third-party software program running
> on the PC that is overloading the RS-232 capacity by sending large
> volumes of commands to the K3. For example Ham Radio Deluxe is known
> to do that, depending on its settings.
>
> If you want to see the IF leakage during transmit you can do that by
> disconnecting the RS-232 cable. Another way is to change the "Xcvr
> Sel" menu selection to "8215 kHz (inverted)" instead of "K3".
>
> I've been resisting making that an official feature because it really
> isn't very reliable. It depends on random leakage through the mixer
> and PIN diode switches in the K3, which are unspecified. It also
> varies with band and transmit power level and may result in too small
> a signal to be useful under some conditions.
>
> The plan is to include a modulation monitor function with the future
> external power sensor option. I've had the hardware done for months
> but have been too busy with the SVGA development to have time to do
> the firmware. Real Soon Now. :=)
>
> Alan N1AL

vk4tux

Re: P3 TX Audio monitoring

In reply to this post by Gary Gregory

Gary, I had replied to your post, perhaps it went to you direct and I am on your naughty list ? ;)

Anyhow if the K3 baud rate (rs-232 config) is not 38400 then that will do it.

Some versions of firmware in the past would sync the K3-P3 to 38400, but I am not sure now.
Anyhow check the baud rate. I used that trick with a PF assigned to change K3 baud rate to other than 38400 to chk my TX. It was good for one over and then would re-sync back to 38400.

cheers

Adrian