K2 RF board test

[Jack-123]

Hi folks

Just building my K2. Got as far as the first resistance checks on the RF
board (page 38)

All values test correct but one.

The right end of R115 is meant to be >500 ohms to earth.
With an analogue meter it gives 2 ohms.
With a DMM on auto range it flashes between ranges wildly. But on manual
range it gives 10.2 Kohms.

Anyone shed any light on this?

Thanks
Jack

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[Jack-123]

Thanks Geoff. I guessed it must be a meter issue. The K2 has just gone on to
pass its first powered up tests (where's my corkscrew? I must celebrate).

The meter was a cheapy, bought to test motorbike magneto ignition :o)

Hows things in the old country?

73
Jack VK2CJC / MM0AXL

----- Original Message -----
From: "Geoffrey Mackenzie-Kennedy" <[hidden email]>
To: "Jack" <[hidden email]>
Sent: Tuesday, February 26, 2008 8:23 PM
Subject: Re: [Elecraft] K2 RF board test

> Jack,
>
> If you do not get a reply which solves your problem please let me know. I
> cannot get to see the schematic until later today, but it looks as though
> there might be a semiconductor connected to the right end of R115 which
> conducts when you use your analogue meter. You could try swapping the
> leads of the analogue meter to see if it then reads a greater resistance
> than 2 ohms, hopefully > 500 ohms. If it does then the analogue meter is
> causing the problem because any analogue meter measuring resistance can
> cause a semiconductor to conduct, DMMs should not.
>
> 73,
> Geoff
> GM4ESD

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[Don Wilhelm-4]

Jack,

Believe the DMM and refrain from using the analog ohmmeter because it
apparently uses a high enough voltage for resistance measurements that
it can turn on solid state devices and may even damage them.

73,
Don W3FPR

Jack wrote:

> Hi folks
>
> Just building my K2. Got as far as the first resistance checks on the
> RF board (page 38)
>
> All values test correct but one.
>
> The right end of R115 is meant to be >500 ohms to earth.
> With an analogue meter it gives 2 ohms.
> With a DMM on auto range it flashes between ranges wildly. But on
> manual range it gives 10.2 Kohms.
>
> Anyone shed any light on this?
>
> Thanks
> Jack
>

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