K1 DC voltage check

[Mark Petrovic]

I'm performing the DC voltage checks (page 30 of the instructions), which occur immediately after installing the power switch on the RF board.  

P1 pin 16 is supposed to be supply minus 300mV, but I get 600mV.  Is this a cause for concern?
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[Don Wilhelm-4]

Mark,

You are effectively reading the voltage drop across D16.
That 600mV drop across D16 will not drastically affect the operation of
the K1.
If you would like a bit higher voltage on the PA transistor, you can
increase the voltage of your power supply a bit (the K1 upper voltage
spec is 15 volts).  If you are running on batteries, it will make a
little difference.
If you would like a lower voltage drop across D16, replace it with a
95SQ015 which is available from Elecraft as p/n E560009 (it is used in
the K2 as the series reverse voltage protection diode.

73,
Don W3FPR

On 2/27/2016 2:32 PM, Mark Petrovic wrote:
> I'm performing the DC voltage checks (page 30 of the instructions), which occur immediately after installing the power switch on the RF board.
>
> P1 pin 16 is supposed to be supply minus 300mV, but I get 600mV.  Is this a cause for concern?
>

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[Mark Petrovic]

Thank you, Don.

What does drastically mean in this context?

> On Feb 27, 2016, at 11:59 AM, Don Wilhelm <[hidden email]> wrote:
>
> Mark,
>
> You are effectively reading the voltage drop across D16.
> That 600mV drop across D16 will not drastically affect the operation of the K1.
> If you would like a bit higher voltage on the PA transistor, you can increase the voltage of your power supply a bit (the K1 upper voltage spec is 15 volts).  If you are running on batteries, it will make a little difference.
> If you would like a lower voltage drop across D16, replace it with a 95SQ015 which is available from Elecraft as p/n E560009 (it is used in the K2 as the series reverse voltage protection diode.
>
> 73,
> Don W3FPR
>
>> On 2/27/2016 2:32 PM, Mark Petrovic wrote:
>> I'm performing the DC voltage checks (page 30 of the instructions), which occur immediately after installing the power switch on the RF board.
>>
>> P1 pin 16 is supposed to be supply minus 300mV, but I get 600mV.  Is this a cause for concern?
>

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[Don Wilhelm-4]

"not drastically" was what was used - trying to mean 'very little'.

73,
Don W3FPR

On 2/27/2016 3:12 PM, Mark Petrovic wrote:

> Thank you, Don.
>
> What does drastically mean in this context?
>
>> On Feb 27, 2016, at 11:59 AM, Don Wilhelm <[hidden email]> wrote:
>>
>> Mark,
>>
>> You are effectively reading the voltage drop across D16.
>> That 600mV drop across D16 will not drastically affect the operation of the K1.
>> If you would like a bit higher voltage on the PA transistor, you can increase the voltage of your power supply a bit (the K1 upper voltage spec is 15 volts).  If you are running on batteries, it will make a little difference.
>> If you would like a lower voltage drop across D16, replace it with a 95SQ015 which is available from Elecraft as p/n E560009 (it is used in the K2 as the series reverse voltage protection diode.
>>
>> 73,
>> Don W3FPR
>>
>>> On 2/27/2016 2:32 PM, Mark Petrovic wrote:
>>> I'm performing the DC voltage checks (page 30 of the instructions), which occur immediately after installing the power switch on the RF board.
>>>
>>> P1 pin 16 is supposed to be supply minus 300mV, but I get 600mV.  Is this a cause for concern?

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