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K3: PTT IN problem - cont'd...

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VK7JB

K3: PTT IN problem - cont'd...

Hello Again,

Well, the PTT IN problem persists.

I can confirm that the K3 is not in TEST mode and that the VOX/PTT parameter is definitely set to PTT.

I've taken the top of the rig and checked that all the rear panel hardware is still connected and in place.

PTT on the front panel mic connector and the XMIT front panel button work normally. It's still only the rear panel PTT IN that's the problem.

Anywhere else I should look before I call support @ Elecraft?

Thanks to all who replied via pm with helpful suggestions,

john
VK7JB

Don Wilhelm-4

Re: K3: PTT IN problem - cont'd...

John,

Due to your time differences, I would suggest emailing [hidden email].

73,
Don W3FPR

On 4/11/2012 8:07 PM, VK7JB wrote:

> Hello Again,
>
> Well, the PTT IN problem persists.
>
> I can confirm that the K3 is not in TEST mode and that the VOX/PTT parameter
> is definitely set to PTT.
>
> I've taken the top of the rig and checked that all the rear panel hardware
> is still connected and in place.
>
> PTT on the front panel mic connector and the XMIT front panel button work
> normally. It's still only the rear panel PTT IN that's the problem.
>
> Anywhere else I should look before I call support @ Elecraft?
>
> Thanks to all who replied via pm with helpful suggestions,
>
>

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Guy, K2AV

Re: K3: PTT IN problem - cont'd...

In reply to this post by VK7JB

Hi, John,

As far as I can tell from the schematic, the PTT_IN jack and the ACC jack
pin 4 are a wire-to-wire connection at Q3 on the KIO3 board. Power on, see
if both PTT_IN center and ACC jack pin 4 show the voltage to ground for
PTT. See if the voltage on one drops if the other is grounded.

If not you have a physical path disrupted and you can trace it. Schematics
are available for download on the Elecraft web site. In Adobe reader,
using CTRL- F to bring up the search widget, type in "PTT IN" without the
quotes will take you to all the line identifications and highlight them.

73, Guy.

On Wed, Apr 11, 2012 at 8:07 PM, VK7JB <[hidden email]> wrote:

> Hello Again,
>
> Well, the PTT IN problem persists.
>
> I can confirm that the K3 is not in TEST mode and that the VOX/PTT
> parameter
> is definitely set to PTT.
>
> I've taken the top of the rig and checked that all the rear panel hardware
> is still connected and in place.
>
> PTT on the front panel mic connector and the XMIT front panel button work
> normally. It's still only the rear panel PTT IN that's the problem.
>
> Anywhere else I should look before I call support @ Elecraft?
>
> Thanks to all who replied via pm with helpful suggestions,
>
> john
> VK7JB
>
> --
> View this message in context:
> http://elecraft.365791.n2.nabble.com/K3-PTT-IN-problem-cont-d-tp7457978p7457978.html
> Sent from the Elecraft mailing list archive at Nabble.com.
> ______________________________________________________________
> 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
>

Joe Subich, W4TV-4

Re: K3: PTT IN problem - cont'd...

On 4/11/2012 8:58 PM, Guy Olinger K2AV wrote:
> Hi, John,
>
> As far as I can tell from the schematic, the PTT_IN jack and the ACC
> jack pin 4 are a wire-to-wire connection at Q3 on the KIO3 board.

Rear panel PTT and KIO3 PTT are paralleled to the front panel (and CPU).
The first thing I would check is for +5V on the PTT jack ... if it's
missing I would check RFC 1 in series with the PTT In jack.

I've had too many failures of the serial RF chokes on the KIO 3 board
(mic - before it was bypassed in the RFI mod, Line Out, Line, In, etc.)
to trust those chokes.

73,

... Joe, W4TV

On 4/11/2012 8:58 PM, Guy Olinger K2AV wrote:

> Hi, John,
>
> As far as I can tell from the schematic, the PTT_IN jack and the ACC jack
> pin 4 are a wire-to-wire connection at Q3 on the KIO3 board. Power on, see
> if both PTT_IN center and ACC jack pin 4 show the voltage to ground for
> PTT. See if the voltage on one drops if the other is grounded.
>
> If not you have a physical path disrupted and you can trace it. Schematics
> are available for download on the Elecraft web site. In Adobe reader,
> using CTRL- F to bring up the search widget, type in "PTT IN" without the
> quotes will take you to all the line identifications and highlight them.
>
> 73, Guy.
>
> On Wed, Apr 11, 2012 at 8:07 PM, VK7JB<[hidden email]> wrote:
>
>> Hello Again,
>>
>> Well, the PTT IN problem persists.
>>
>> I can confirm that the K3 is not in TEST mode and that the VOX/PTT
>> parameter
>> is definitely set to PTT.
>>
>> I've taken the top of the rig and checked that all the rear panel hardware
>> is still connected and in place.
>>
>> PTT on the front panel mic connector and the XMIT front panel button work
>> normally. It's still only the rear panel PTT IN that's the problem.
>>
>> Anywhere else I should look before I call support @ Elecraft?
>>
>> Thanks to all who replied via pm with helpful suggestions,
>>
>> john
>> VK7JB
>>
>> --
>> View this message in context:
>> http://elecraft.365791.n2.nabble.com/K3-PTT-IN-problem-cont-d-tp7457978p7457978.html
>> Sent from the Elecraft mailing list archive at Nabble.com.
>> ______________________________________________________________
>> 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
>>
> ______________________________________________________________
> 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
>

VK7JB

Re: K3: PTT IN problem - cont'd...

Thanks Joe & Guy. I've had a look at the schematic and that makes sense. I'll have a look for the 5V on the PTT IN connector and if it's missing, I'll trace it back. I'll take the K3 apart tonight and make a start.
If it turns out to be an open RFC, that'll be a simple fix.

Thinking back, I had an RFC go open on my K1 at one stage way back, for no apparent reason. Took me a while to find it because at the time, I really didn't think RFC's were that fragile and that thew me off. Anyway, I learnt a lesson. Perhaps the same one here... we'll see.

Thanks for the advice.

John
VK7JB

VK7JB

Re: K3: PTT IN problem - cause found...Joe picked it...

Thanks Joe - you picked it in one! No voltage on PTT IN. RFC1 on the RF board has failed open (9 M Ohm on my meter) and bypassing it restores the PTT IN 5V line voltage and function, as you'd expect.

It's a surface mount component on the bottom of the RF board, for those who might need to know in the future.

Next challenge is to replace it - I'm not very experience with SMC building, but I'll give it a go. Or, would there be any problem replacing it with a standard RFC of the same value if I can configure it to fit?

73,

John
VK7B

Geoffrey Mackenzie-Kennedy-3

Re: K3: PTT IN problem - cause found...Joe picked it...

John,

To add to Ron's advice, If you use tweezers to hold the part, do not use the
type known as Locking Tweezers. These are guaranteed to launch the SMD
across the room.

Also,

If you have a cat, bolt the cat to the floor or bribe it not to help.

73,

Geoff
LX2AO

On April 12, 2012 at 16:52 +0200, Ron D'Eau Claire wrote:

>A two-terminal SMD is very easy to replace. Find a small, thin tool (e.g.
> tiny screwdriver, tip of a knife blade or even a toothpick) and place it
> where the SMD body touches the board and lift up on the SMD while heating
> one end with your soldering iron. It will tilt up, held by the solder at
> the
> other end. Now touch the other end with your iron while holding the part
> with small needle nose pliers or tweezers to free it.

<snip>

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Rick Tavan N6XI

Re: K3: PTT IN problem - cause found...Joe picked it...

In reply to this post by VK7JB

Having recently done my first SMD board, I'd like to add one tip that made
it easier for me. Instead of tinning both pads, I tinned only one. Then I
held the part with tweezers, flat on the board, just touching the lump of
solder. I re-heated the solder and slid the part over onto the pad, holding
it still as the solder solidified. Then I soldered the other pad. This
leaves the part nicely flat against the board, with no need to push the
part down through hot solder while bending it through cold solder on the
other side. I used curved, padded handle, very sharp tweezers designed for
the purpose and an Optivisor magnifier. I did about a hundred of these and
it felt pretty good right from the start.

Warning: I am a definite SMD newbie and my advice may not be technically
correct. It seemed to work for me, though.

73,

/Rick

On Thu, Apr 12, 2012 at 7:52 AM, Ron D'Eau Claire <[hidden email]> wrote:

> A two-terminal SMD is very easy to replace. Find a small, thin tool (e.g.
> tiny screwdriver, tip of a knife blade or even a toothpick) and place it
> where the SMD body touches the board and lift up on the SMD while heating
> one end with your soldering iron. It will tilt up, held by the solder at
> the
> other end. Now touch the other end with your iron while holding the part
> with small needle nose pliers or tweezers to free it.
>
> Clean any excess solder off of the pads and leave a small drop of fresh
> solder on each pad.
>
> Set the new part in place and hold it in place with the little tool you
> used
> to pry the old part off with earlier. Touch one end, then the other with
> your soldering iron to "sweat-solder" the part in place. Optionally, you
> can
> clean off the pads entirely and have a tiny drop of solder on the tip of
> your iron that will flow onto the solder pad when you touch each end.
> That's
> a little trickier to do at first. Most people tend to have too big of a
> drop
> of solder on the iron. If your first just make a "bump" of fresh solder on
> each pad and wipe your iron before touching it to the joint, you won't have
> excess solder.
>
> --

Rick Tavan N6XI
Truckee, CA
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kevinr@coho.net

Re: K3: PTT IN problem - cause found...Joe picked it...

I am fairly new to SMD soldering and rework. I found these tutorials
which may help you remove and install that RFC.

The first of four is located here: http://www.sparkfun.com/tutorials/36

Good luck and have fun,
Kevin. KD5ONS

On 4/12/2012 10:13 AM, Rick Tavan N6XI wrote:

> Having recently done my first SMD board, I'd like to add one tip that made
> it easier for me. Instead of tinning both pads, I tinned only one. Then I
> held the part with tweezers, flat on the board, just touching the lump of
> solder. I re-heated the solder and slid the part over onto the pad, holding
> it still as the solder solidified. Then I soldered the other pad. This
> leaves the part nicely flat against the board, with no need to push the
> part down through hot solder while bending it through cold solder on the
> other side. I used curved, padded handle, very sharp tweezers designed for
> the purpose and an Optivisor magnifier. I did about a hundred of these and
> it felt pretty good right from the start.
>
> Warning: I am a definite SMD newbie and my advice may not be technically
> correct. It seemed to work for me, though.
>
> 73,
>
> /Rick
>
> On Thu, Apr 12, 2012 at 7:52 AM, Ron D'Eau Claire<[hidden email]> wrote:
>
>> A two-terminal SMD is very easy to replace. Find a small, thin tool (e.g.
>> tiny screwdriver, tip of a knife blade or even a toothpick) and place it
>> where the SMD body touches the board and lift up on the SMD while heating
>> one end with your soldering iron. It will tilt up, held by the solder at
>> the
>> other end. Now touch the other end with your iron while holding the part
>> with small needle nose pliers or tweezers to free it.
>>
>> Clean any excess solder off of the pads and leave a small drop of fresh
>> solder on each pad.
>>
>> Set the new part in place and hold it in place with the little tool you
>> used
>> to pry the old part off with earlier. Touch one end, then the other with
>> your soldering iron to "sweat-solder" the part in place. Optionally, you
>> can
>> clean off the pads entirely and have a tiny drop of solder on the tip of
>> your iron that will flow onto the solder pad when you touch each end.
>> That's
>> a little trickier to do at first. Most people tend to have too big of a
>> drop
>> of solder on the iron. If your first just make a "bump" of fresh solder on
>> each pad and wipe your iron before touching it to the joint, you won't have
>> excess solder.
>>
>> --
> Rick Tavan N6XI
> Truckee, CA
> ______________

VK7JB

Re: K3: PTT IN problem - cause found...Thanks from VK7JB

A note of thanks to everyone who offered me helpful advice and tips, on and off-list.
Elecraft are sending me some replacement RFC1's and I feel a bit more confident about replacing it after all of your sage advice.
This is a great group and I value your collective knowlege and generosity in sharing it.

73,
John
VK7JB

Tony

Re: K3: PTT IN problem - cause found...Thanks from VK7JB

Hi all looking for a second hand P3 and used 10watt k3
73 tony G0GMS

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of VK7JB
Sent: 13 April 2012 12:37
To: [hidden email]
Subject: Re: [Elecraft] K3: PTT IN problem - cause found...Thanks from VK7JB

A note of thanks to everyone who offered me helpful advice and tips, on and
off-list.
Elecraft are sending me some replacement RFC1's and I feel a bit more
confident about replacing it after all of your sage advice.
This is a great group and I value your collective knowlege and generosity in
sharing it.

73,
John
VK7JB

--
View this message in context:
http://elecraft.365791.n2.nabble.com/K3-PTT-IN-problem-cont-d-tp7457978p7462
415.html
Sent from the Elecraft mailing list archive at Nabble.com.
______________________________________________________________
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John Lemay

Re: K3: PTT IN problem - cause found...Thanks from VK7JB

Tony

Can I suggest that you might have a better response if you start your own
message with a suitable header, instead of tagging on to an unrelated
message ?

Regards

John G4ZTR

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of Tony Read
Sent: 17 April 2012 08:15
To: [hidden email]
Subject: Re: [Elecraft] K3: PTT IN problem - cause found...Thanks from VK7JB

Hi all looking for a second hand P3 and used 10watt k3
73 tony G0GMS

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of VK7JB
Sent: 13 April 2012 12:37
To: [hidden email]
Subject: Re: [Elecraft] K3: PTT IN problem - cause found...Thanks from VK7JB

A note of thanks to everyone who offered me helpful advice and tips, on and
off-list.
Elecraft are sending me some replacement RFC1's and I feel a bit more
confident about replacing it after all of your sage advice.
This is a great group and I value your collective knowlege and generosity in
sharing it.

73,
John
VK7JB

--
View this message in context:
http://elecraft.365791.n2.nabble.com/K3-PTT-IN-problem-cont-d-tp7457978p7462
415.html
Sent from the Elecraft mailing list archive at Nabble.com.
______________________________________________________________
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