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KX1 Newby Help!

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Burke Jones

KX1 Newby Help!

Okay, I am a complete electronics "newby" - so please be patient.

I have worked my way carefully up to page 26 on my KX1. I have double checked everything, but I may need to do it again.

The problem is with the resistance checks.

On U1 I have several pins that provide no resitance, by "no" I mean not even zero - my DMM just shows nothing.

On U3 pin 1 and pen 8 show nothing as well.

This is true even if I touch the solder points on the bottom instead of the pin holes or legs.

Also when I check the diodes D2 and D3 the Ohms just keep getting higher and higher. In other words when I touch the banded end of the diode the resistance just keeps increasing as long as the probe is on the lead. Is this correct?

Any help would be much appreciated! This is my first kit, and while I know basically nothing about electronics I am good a physically constructing things and I am careful in my work.

Burke Jones

N0HYD

Olathe, KS

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Don Wilhelm-4

Re: KX1 Newby Help!

Burke,

What do you mean by "nothing"? I am going to guess that it means the
DMM indicates the same as when you have nothing connected to the leads
and the DMM is set to read resistance (correct me if I am wrong).

If my assumption (guess) is correct, that is the indication for infinite
resistance (i.e. an open circuit) for your DMM.

Now - consider the meaning of the ">" indicator. That is the symbol for
"greater than". Infinite resistance *is* greater than the value
indicated, so if my assumption is correct, you have no problem.

A DMM resistance reading that continues to climb usually indicates that
the DMM current is charging a large capacitor. As long as the lowest
reading is greater than that indicated in the manual, no problem exists.

Realize that at this point the resistance measurements are checking for
shorts.(with the exceptions of the readings that are < (less than) 5k),
so any measurement that is greater than the indicated value (to include
infinite resistance = open circuit) passes the test.

73,
Don W3FPR

Burke Jones wrote:

> Okay, I am a complete electronics "newby" - so please be patient.
>
> I have worked my way carefully up to page 26 on my KX1. I have double
> checked everything, but I may need to do it again.
>
> The problem is with the resistance checks.
>
> On U1 I have several pins that provide no resitance, by "no" I mean
> not even zero - my DMM just shows nothing.
>
> On U3 pin 1 and pen 8 show nothing as well.
>
> This is true even if I touch the solder points on the bottom instead
> of the pin holes or legs.
>
> Also when I check the diodes D2 and D3 the Ohms just keep getting
> higher and higher. In other words when I touch the banded end of the
> diode the resistance just keeps increasing as long as the probe is on
> the lead. Is this correct?
>
> Any help would be much appreciated! This is my first kit, and while I
> know basically nothing about electronics I am good a physically
> constructing things and I am careful in my work.
>
> Burke Jones
> N0HYD
> Olathe, KS
>

Burke Jones

Re: KX1 Newby Help!

Don, Philip & Paul -

Thank you guys so much for the help! It turns out I was confusing "infinite resistance" with "zero resistance" - it looks like I am good to go ahead with the next step.

I have a steady hand and I am good at following the excellent direction provided by Elecraft - so with your occasional help, this project should end successfully!

Again, thanks for the clear and patient explanations.

Burke Jones

N0HYD

Olathe, KS

On Mon, Dec 22, 2008 at 9:08 PM, Don Wilhelm <[hidden email]> wrote:

Burke,

What do you mean by "nothing"? I am going to guess that it means the DMM indicates the same as when you have nothing connected to the leads and the DMM is set to read resistance (correct me if I am wrong).

If my assumption (guess) is correct, that is the indication for infinite resistance (i.e. an open circuit) for your DMM.

Now - consider the meaning of the ">" indicator. That is the symbol for "greater than". Infinite resistance *is* greater than the value indicated, so if my assumption is correct, you have no problem.

A DMM resistance reading that continues to climb usually indicates that the DMM current is charging a large capacitor. As long as the lowest reading is greater than that indicated in the manual, no problem exists.

Realize that at this point the resistance measurements are checking for shorts.(with the exceptions of the readings that are < (less than) 5k), so any measurement that is greater than the indicated value (to include infinite resistance = open circuit) passes the test.

73,
Don W3FPR

Burke Jones wrote:

Okay, I am a complete electronics "newby" - so please be patient.
I have worked my way carefully up to page 26 on my KX1. I have double checked everything, but I may need to do it again.
The problem is with the resistance checks.
On U1 I have several pins that provide no resitance, by "no" I mean not even zero - my DMM just shows nothing.
On U3 pin 1 and pen 8 show nothing as well.
This is true even if I touch the solder points on the bottom instead of the pin holes or legs.
Also when I check the diodes D2 and D3 the Ohms just keep getting higher and higher. In other words when I touch the banded end of the diode the resistance just keeps increasing as long as the probe is on the lead. Is this correct?
Any help would be much appreciated! This is my first kit, and while I know basically nothing about electronics I am good a physically constructing things and I am careful in my work.
Burke Jones
N0HYD
Olathe, KS