KAT500 Antenna Grounding

[Bob McGraw - K4TAX]

I didn't find the answer in the manual, so I'll ask here.   I do see in
the manual where bleed resistors are applied to the unused antenna
terminals to bleed off static charges.  {page 15, Antenna
Selector......... etc}

My question, do the relays in the tuner take the center conductor of all
three antenna terminals to ground when power is removed? I see that it
switches to ANT 1 when power is off.    I suppose I could remove the
covers and explore for myself, and I'll do just that if no one confirms
one way or the other.   Anyone have a schematic?  That would be nice.


73

Bob, K4TAX



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[Wes Stewart-2]

Unpowered, the input is connected to Ant 1.  Each output has a 1 meg resistor to
ground, other than that just open relay contacts.

Wes  N7WS.


  On 9/17/2018 7:00 PM, Bob McGraw K4TAX wrote:

> I didn't find the answer in the manual, so I'll ask here.   I do see in the
> manual where bleed resistors are applied to the unused antenna terminals to
> bleed off static charges.  {page 15, Antenna Selector......... etc}
>
> My question, do the relays in the tuner take the center conductor of all three
> antenna terminals to ground when power is removed? I see that it switches to
> ANT 1 when power is off.    I suppose I could remove the covers and explore
> for myself, and I'll do just that if no one confirms one way or the other.  
> Anyone have a schematic?  That would be nice.
>
>
> 73
>
> Bob, K4TAX
>

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[Bob McGraw - K4TAX]

Thanks Wes.     I hesitated to un-stack the KPA500 off of the KAT500 and
disconnect all the cables.    I suppose I need to look at my
configuration to reduce the likelihood of any damage to the PIN diodes
in the KPA500.   Lightning protection is good on the outside of the
house but static discharge probably needs review.

73

Bob, K4TAX


On 9/17/2018 10:30 PM, Wes Stewart wrote:
> Unpowered, the input is connected to Ant 1.  Each output has a 1 meg
> resistor to ground, other than that just open relay contacts.
>
> Wes  N7WS.


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[Jim Brown-10]

On 9/18/2018 6:15 AM, Bob McGraw K4TAX wrote:
> Lightning protection is good on the outside of the house but static
> discharge probably needs review.

Bob,

Take a look at the arrestors that Array Solutions sells, which are the
circuit that were built under the ICE name until the owner died a decade
or so ago, and that they sold. I'm now using them, and have them mounted
in a large Hoffman enclosure. I like the circuit because I believe it is
a better solution to the discharge problem, and I like their
construction because the GDT is user replaceable. If you lose the GDT in
a Polyphaser you throw it away and buy a new one.

https://www.arraysolutions.com/surge-and-rf-protection/as-303u

73, Jim K9YC

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