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K1 - Front Panel - Nothing on LCD

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VP8ROT

K1 - Front Panel - Nothing on LCD

Hello, I am building a K1 and have come up against a problem I can't solve at the " Alignment and Test, part 1".

Here you power the K1 for the first time with the RF, filter and front boards connected. After the LEDs do their test the LCD screen should show an error code. Nothing appears on my screen.

I have checked all chip orientations and to the best of my knowledge check for shorts on the switches (they go from + volts to zero when pressed). There are no obvious solder problems on the board.

Please could someone suggest any tests I should perform to find the source of my problem.

Many thanks,

Ian, VP8ROT
Rothera
Antarctica

Don Wilhelm-4

Re: K1 - Front Panel - Nothing on LCD

Ian,

The very most likely problem is that you have a soldering joint failure.
Look very critically at your solder connections. Is there just a slight
bit more solder applied than that required to fill the thru-plated
hole? Do all the solder joints have a smooth concave slope on the
sides? Do the edges of the solder joint taper out to an almost
invisible edge on both the solder pad and the component lead?

If the answer to any of the above questions is yes, then your soldering
is certainly suspect. You must apply enough heat to cause the solder to
flow out onto the solder pad and down into the thru-plated hole. Any
solder connections that have a blob of solder on them are not well
soldered connections. An excess of solder can hide a poorly soldered
joint, and in fact is the usual appearance of a bad solder joint.

Review the figures in the soldering tutorial on the Elecraft website if
necessary.

73,
Don W3FPR

VP8ROT wrote:

> Hello, I am building a K1 and have come up against a problem I can't solve at
> the " Alignment and Test, part 1".
>
> Here you power the K1 for the first time with the RF, filter and front
> boards connected. After the LEDs do their test the LCD screen should show an
> error code. Nothing appears on my screen.
>
> I have checked all chip orientations and to the best of my knowledge check
> for shorts on the switches (they go from + volts to zero when pressed).
> There are no obvious solder problems on the board.
>
> Please could someone suggest any tests I should perform to find the source
> of my problem.
>
> Many thanks,
>
> Ian, VP8ROT
> Rothera
> Antarctica
>
>

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Augie "Gus" Hansen

Re: K1 - Front Panel - Nothing on LCD

Hi Don,

Given the way you phrased the questions, I believe that a "no" answer to
one or more would indicate a soldering problem. Wouldn't "yes" to all
indicate successful soldering?

> ...
> The very most likely problem is that you have a soldering joint failure.
> Look very critically at your solder connections. Is there just a
> slight bit more solder applied than that required to fill the
> thru-plated hole? Do all the solder joints have a smooth concave
> slope on the sides? Do the edges of the solder joint taper out to an
> almost invisible edge on both the solder pad and the component lead?
>
> If the answer to any of the above questions is yes, then your
> soldering is certainly suspect. You must apply enough heat to cause
> the solder to flow out onto the solder pad and down into the
> thru-plated hole. Any solder connections that have a blob of solder
> on them are not well soldered connections. An excess of solder can
> hide a poorly soldered joint, and in fact is the usual appearance of a
> bad solder joint.

Gus Hansen
KB0YH

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Don Wilhelm-4

Re: K1 - Front Panel - Nothing on LCD

Angie,

You are quite correct - can we blame it on a 'senior moment'?
I do trust the point was made, and I will not publish a correction other
than this post.

Just as verification of my points - I just finished a KX1 repair and
except for one misplaced component, the problems were all due to excess
solder and inadequately heated solder pads. At least 5 problems were
identified, but then I removed the excess solder and re-soldered
components in a large area each time, so who knows how many more were
actually present. This *is the* most common cause of kit building failure.

73,
Don W3FPR

Augie Hansen wrote:

> Hi Don,
>
> Given the way you phrased the questions, I believe that a "no" answer
> to one or more would indicate a soldering problem. Wouldn't "yes" to
> all indicate successful soldering?
>> ...
>> The very most likely problem is that you have a soldering joint failure.
>> Look very critically at your solder connections. Is there just a
>> slight bit more solder applied than that required to fill the
>> thru-plated hole? Do all the solder joints have a smooth concave
>> slope on the sides? Do the edges of the solder joint taper out to an
>> almost invisible edge on both the solder pad and the component lead?
>>
>> If the answer to any of the above questions is yes, then your
>> soldering is certainly suspect. You must apply enough heat to cause
>> the solder to flow out onto the solder pad and down into the
>> thru-plated hole. Any solder connections that have a blob of solder
>> on them are not well soldered connections. An excess of solder can
>> hide a poorly soldered joint, and in fact is the usual appearance of
>> a bad solder joint.
>
> Gus Hansen
> KB0YH
>
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VP8ROT

Re: K1 - Front Panel - Nothing on LCD

In reply to this post by VP8ROT

Hi Don, I bow to your genius. The problem appears to be a soldering issue with the main chip. I was very lucky in that I was able to remove the solder from one side of the LCD and lift it up enough to get to the chip soldering points. A re-solder of each pin and all is well with the world.

Very lucky, as the next post for me arrives late October.

I wonder if it would be worth adding a test stage pre-LCD install to prevent juniors like myself going down this route.

Hopefully I'll have time to complete in the next few weeks and be transmitting from the hills of Adelaide Island when the sun comes back.

Many thanks again
73,
Ian - VP8ROT (G0VZM)

----- Original Message ----
From: Don Wilhelm <[hidden email]>
To: VP8ROT <[hidden email]>
Cc: [hidden email]
Sent: Tuesday, 10 June, 2008 12:45:35 PM
Subject: Re: [Elecraft] K1 - Front Panel - Nothing on LCD

Ian,

The very most likely problem is that you have a soldering joint failure.
Look very critically at your solder connections. Is there just a slight
bit more solder applied than that required to fill the thru-plated
hole? Do all the solder joints have a smooth concave slope on the
sides? Do the edges of the solder joint taper out to an almost
invisible edge on both the solder pad and the component lead?

If the answer to any of the above questions is yes, then your soldering
is certainly suspect. You must apply enough heat to cause the solder to
flow out onto the solder pad and down into the thru-plated hole. Any
solder connections that have a blob of solder on them are not well
soldered connections. An excess of solder can hide a poorly soldered
joint, and in fact is the usual appearance of a bad solder joint.

Review the figures in the soldering tutorial on the Elecraft website if
necessary.

73,
Don W3FPR

VP8ROT wrote:

Don Wilhelm-4

Re: K1 - Front Panel - Nothing on LCD

Ian,

Glad you found it. Keep warm down there!
Yes, soldering is *the* most common builder problem. When in doubt,
check the soldering, then re-check the soldering, and when that is done
- check the soldering.

For those just starting to build, use an iron temperature at about 750
degrees F (800 for the KPA100), and watch carefully for the solder to
flow - if you do not see the solder wicked into the thru-plated hole, it
is not a good solder connection. Use a small diameter solder to assist
in controlling the amount (I prefer .015 inch diameter in a 63/37 alloy
with a midly activated rosin flux). Too much solder can be just as bad
as not enough.

73,
Don W3FPR

Ian Nightingale wrote:

> Hi Don, I bow to your genius. The problem appears to be a soldering issue with the main chip. I was very lucky in that I was able to remove the solder from one side of the LCD and lift it up enough to get to the chip soldering points. A re-solder of each pin and all is well with the world.
>
> Very lucky, as the next post for me arrives late October.
>
> I wonder if it would be worth adding a test stage pre-LCD install to prevent juniors like myself going down this route.
>
> Hopefully I'll have time to complete in the next few weeks and be transmitting from the hills of Adelaide Island when the sun comes back.
>
> Many thanks again
> 73,
> Ian - VP8ROT (G0VZM)
>
>> 7:20 AM
>>