Remoting KAT500 to base of antenna

[k6dgw]

I'm sending this to the list, many often ask that discussions that might
apply to others *not* be taken off-line.

After 38 years on a 5 acre "farm" in Auburn CA, we moved last fall.
This spring I will install a flag pole vertical in the backyard of our
new [to us] home in Sparks NV.  I will also have an end-fed wire along
the fence, commencing adjacent to the flag pole.  I want to remote my
KAT500 at the base of the flag pole, and use it as both a auto-tuner and
a remote antenna switch between the two antennas.  My HOA will be happy,
I'll be able to make some RF and see my P3 at home, and I also can run
remote to W7RN where the coefficient of aerial aluminum is very high.

I know that the KAT500 won't likely directly match the end-fed wire, I
know how to deal with that, and I know that no "antenna tuner" has ever
actually "tuned" an antenna. :-)

I will have about 120' of 2 1/2" PVC buried from the shack to the pole
and will have room in it for power, coax, and control cables.  I plan to
have the KAT500 & power supply in a weather-proof box at the base of the
pole.

1.  Can I extend the AUX connections into the shack so the KAT500 will
track the receiver?  If so, what kind of cable is required [I've heard
CAT-5 will work?]

2.  Do I need to run any other circuits, other than coax and the AUX,
from KAT500 into shack?

3.  Reno/Sparks is a high desert [4,500'] directly adjacent to the
Carson Range and Sierra Nevada [really big mountains].  Winter temps go
down into single digits, it does snow/rain.  Should I do anything to
prevent condensation in the weatherproof box [light bulb, drain hole, ???].

73,

Fred K6DGW
- Northern California Contest Club
- CU in the Cal QSO Party 1-2 Oct 2016
- www.cqp.org
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

[ab2tc]

Hi Fred,

I have been running my remote KAT500 for 3 CNY winters straight now without any problems. My connection to the site (about 100 feet) is LMR400DB and power (heavy duty extension cord) only. The communications is WiFi using a Lantronics serial server talking to the KAT500 utility. I tried using Ethernet for the communications but the noise and spurs were pretty bad. As to your numbered questions:

1. I don't know as I have never tried or missed the AUX connection, but I have also heard that other people have been successful with CAT5 or CAT6 cable.

2. I think having the serial connection to the KAT500 is very useful. Of course it is essential if you don't have the AUX connection (I don't).

3. It  looks like I have about the same winter conditions as I do. My enclosure is entirely open at the bottom and all cables come up here with a drip loop. I have no heating system installed. If you think one is necessary be sure to turn off during summer. BTW my installation is almost completely shaded by heavy foliage in the summer. See a couple of pictures here:

http://ab2tc.com/

AB2TC - Knut

k6dgw wrote

I'm sending this to the list, many often ask that discussions that might
apply to others *not* be taken off-line.

After 38 years on a 5 acre "farm" in Auburn CA, we moved last fall.
This spring I will install a flag pole vertical in the backyard of our
new [to us] home in Sparks NV.  I will also have an end-fed wire along
the fence, commencing adjacent to the flag pole.  I want to remote my
KAT500 at the base of the flag pole, and use it as both a auto-tuner and
a remote antenna switch between the two antennas.  My HOA will be happy,
I'll be able to make some RF and see my P3 at home, and I also can run
remote to W7RN where the coefficient of aerial aluminum is very high.

I know that the KAT500 won't likely directly match the end-fed wire, I
know how to deal with that, and I know that no "antenna tuner" has ever
actually "tuned" an antenna. :-)

I will have about 120' of 2 1/2" PVC buried from the shack to the pole
and will have room in it for power, coax, and control cables.  I plan to
have the KAT500 & power supply in a weather-proof box at the base of the
pole.

1.  Can I extend the AUX connections into the shack so the KAT500 will
track the receiver?  If so, what kind of cable is required [I've heard
CAT-5 will work?]

2.  Do I need to run any other circuits, other than coax and the AUX,
from KAT500 into shack?

3.  Reno/Sparks is a high desert [4,500'] directly adjacent to the
Carson Range and Sierra Nevada [really big mountains].  Winter temps go
down into single digits, it does snow/rain.  Should I do anything to
prevent condensation in the weatherproof box [light bulb, drain hole, ???].

73,

Fred K6DGW
- Northern California Contest Club
- CU in the Cal QSO Party 1-2 Oct 2016
- www.cqp.org
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

[Edward R Cole]

Fred,

Your high desert climate will probably produce less condensation than
my sub-arctic/maritime environ.  What I do for enclosures is to not
seal them airtight but provide good drain openings which air can
exchange.  Of course the shelter is made to repel direct rain/snow.

I suspected that my TR relays were "freezing up" at lower temps
making the action delayed so I used some big aluminum  Dale resistor
strapped onto the relays to add direct heat by conduction.  I happen
to have 28v equipment so used 28v thru the resistors to produce heat
within their wattage rating (used 40w resistors at both relays).  Of
course this also provided some heating of the ambient air of the
enclosure which helped keep moisture from forming even in 90%
humidity of the fall.  It rains 8-days with one day off from August
to October when temps finally drop below freezing and rain becomes
snow.  You don't have anything near that.

One thing I have noticed about drain holes in some equipment is they
are too small to allow water to drop free due to surface tension and
in my environ that results in the weep holes freezing tight.  I drill
them out to 1/4 inch.  Of course if you are prone to insect/archnid
invasion that is problematic.

PS: I lived five years in the high Mojave Desert so know all about
"critters of the desert" (never stick your hand into a confined space
before kicking it to see what crawls out or "rattles"!

73, Ed - KL7UW
------------------------------------------

3.  Reno/Sparks is a high desert [4,500'] directly adjacent to the
Carson Range and Sierra Nevada [really big mountains].  Winter temps go
down into single digits, it does snow/rain.  Should I do anything to
prevent condensation in the weatherproof box [light bulb, drain hole, ???].

73,

Fred K6DGW
- Northern California Contest Club
- CU in the Cal QSO Party 1-2 Oct 2016
- www.cqp.org


73, Ed - KL7UW
http://www.kl7uw.com
     "Kits made by KL7UW"
Dubus Mag business:
     [hidden email]

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

[gm3sek]

I agree with Ed's experience in a damp climate.

One solution to venting an enclosure without letting in water or
wildlife is a 'membrane vent' made from Gore-Tex material. These are
available ready mounted in screw-in plugs (for example eBay item
#252244715964).

73 from Ian GM3SEK

>-----Original Message-----
>From: Elecraft [mailto:[hidden email]] On Behalf Of
>Edward R Cole
>Sent: 20 January 2016 08:29
>To: [hidden email]
>Subject: Re: [Elecraft] Remoting KAT500 to base of antenna
>
>Fred,
>
>Your high desert climate will probably produce less condensation than
>my sub-arctic/maritime environ.  What I do for enclosures is to not
>seal them airtight but provide good drain openings which air can
>exchange.  Of course the shelter is made to repel direct rain/snow.
>
>I suspected that my TR relays were "freezing up" at lower temps
>making the action delayed so I used some big aluminum  Dale resistor
>strapped onto the relays to add direct heat by conduction.  I happen
>to have 28v equipment so used 28v thru the resistors to produce heat
>within their wattage rating (used 40w resistors at both relays).  Of
>course this also provided some heating of the ambient air of the
>enclosure which helped keep moisture from forming even in 90%
>humidity of the fall.  It rains 8-days with one day off from August
>to October when temps finally drop below freezing and rain becomes
>snow.  You don't have anything near that.
>
>One thing I have noticed about drain holes in some equipment is they
>are too small to allow water to drop free due to surface tension and
>in my environ that results in the weep holes freezing tight.  I drill
>them out to 1/4 inch.  Of course if you are prone to insect/archnid
>invasion that is problematic.
>
>PS: I lived five years in the high Mojave Desert so know all about
>"critters of the desert" (never stick your hand into a confined space
>before kicking it to see what crawls out or "rattles"!
>
>73, Ed - KL7UW
>------------------------------------------

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

[David Cutter]

From my work in the food industry (if memory serves), critter invasion is
prevented with 0.64mm square nylon netting.  This is common in the
dress-making industry.  (I think it can also be found as a stainless steel
gauze).  This can be glued over a breather (drip) hole in the base.

David
G3UNA


----- Original Message -----
From: "Edward R Cole" <[hidden email]>
To: <[hidden email]>
Sent: Wednesday, January 20, 2016 8:29 AM
Subject: Re: [Elecraft] Remoting KAT500 to base of antenna

> Fred,
>
> Your high desert climate will probably produce less condensation than my
> sub-arctic/maritime environ.  What I do for enclosures is to not seal them
> airtight but provide good drain openings which air can exchange.  Of
> course the shelter is made to repel direct rain/snow.
>
> I suspected that my TR relays were "freezing up" at lower temps making the
> action delayed so I used some big aluminum  Dale resistor strapped onto
> the relays to add direct heat by conduction.  I happen to have 28v
> equipment so used 28v thru the resistors to produce heat within their
> wattage rating (used 40w resistors at both relays).  Of course this also
> provided some heating of the ambient air of the enclosure which helped
> keep moisture from forming even in 90% humidity of the fall.  It rains
> 8-days with one day off from August to October when temps finally drop
> below freezing and rain becomes snow.  You don't have anything near that.
>
> One thing I have noticed about drain holes in some equipment is they are
> too small to allow water to drop free due to surface tension and in my
> environ that results in the weep holes freezing tight.  I drill them out
> to 1/4 inch.  Of course if you are prone to insect/archnid invasion that
> is problematic.
>
> PS: I lived five years in the high Mojave Desert so know all about
> "critters of the desert" (never stick your hand into a confined space
> before kicking it to see what crawls out or "rattles"!
>
> 73, Ed - KL7UW
> ------------------------------------------
>
> 3.  Reno/Sparks is a high desert [4,500'] directly adjacent to the
> Carson Range and Sierra Nevada [really big mountains].  Winter temps go
> down into single digits, it does snow/rain.  Should I do anything to
> prevent condensation in the weatherproof box [light bulb, drain hole,
> ???].
>
> 73,
>
> Fred K6DGW
> - Northern California Contest Club
> - CU in the Cal QSO Party 1-2 Oct 2016
> - www.cqp.org
>
>
> 73, Ed - KL7UW
> http://www.kl7uw.com
>     "Kits made by KL7UW"
> Dubus Mag business:
>     [hidden email]
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

[Lewis Phelps]

But might not this re-introduce the surface tension problem?

Lew N6LEW

> On Jan 20, 2016, at 10:18 AM, David Cutter <[hidden email]> wrote:
>
> From my work in the food industry (if memory serves), critter invasion is prevented with 0.64mm square nylon netting.  This is common in the dress-making industry.  (I think it can also be found as a stainless steel gauze). This can be glued over a breather (drip) hole in the base.
>
> David
> G3UNA
>
>
> ----- Original Message ----- From: "Edward R Cole" <[hidden email] <mailto:[hidden email]>>
> To: <[hidden email] <mailto:[hidden email]>>
> Sent: Wednesday, January 20, 2016 8:29 AM
> Subject: Re: [Elecraft] Remoting KAT500 to base of antenna
>
>
>> Fred,
>>
>> Your high desert climate will probably produce less condensation than my sub-arctic/maritime environ.  What I do for enclosures is to not seal them airtight but provide good drain openings which air can exchange.  Of course the shelter is made to repel direct rain/snow.
>>
>> I suspected that my TR relays were "freezing up" at lower temps making the action delayed so I used some big aluminum  Dale resistor strapped onto the relays to add direct heat by conduction.  I happen to have 28v equipment so used 28v thru the resistors to produce heat within their wattage rating (used 40w resistors at both relays).  Of course this also provided some heating of the ambient air of the enclosure which helped keep moisture from forming even in 90% humidity of the fall.  It rains 8-days with one day off from August to October when temps finally drop below freezing and rain becomes snow.  You don't have anything near that.
>>
>> One thing I have noticed about drain holes in some equipment is they are too small to allow water to drop free due to surface tension and in my environ that results in the weep holes freezing tight.  I drill them out to 1/4 inch.  Of course if you are prone to insect/archnid invasion that is problematic.
>>
>> PS: I lived five years in the high Mojave Desert so know all about "critters of the desert" (never stick your hand into a confined space before kicking it to see what crawls out or "rattles"!
>>
>> 73, Ed - KL7UW
>> ------------------------------------------
>>
>> 3.  Reno/Sparks is a high desert [4,500'] directly adjacent to the
>> Carson Range and Sierra Nevada [really big mountains].  Winter temps go
>> down into single digits, it does snow/rain.  Should I do anything to
>> prevent condensation in the weatherproof box [light bulb, drain hole, ???].
>>
>> 73,
>>
>> Fred K6DGW
>> - Northern California Contest Club
>> - CU in the Cal QSO Party 1-2 Oct 2016
>> - www.cqp.org
>>
>>
>> 73, Ed - KL7UW
>> http://www.kl7uw.com
>>    "Kits made by KL7UW"
>> Dubus Mag business:
>>    [hidden email]
>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to [hidden email] <mailto:[hidden email]>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft <http://mailman.qth.net/mailman/listinfo/elecraft>
> Help: http://mailman.qth.net/mmfaq.htm <http://mailman.qth.net/mmfaq.htm>
> Post: mailto:[hidden email] <mailto:[hidden email]>
>
> This list hosted by: http://www.qsl.net <http://www.qsl.net/>
> Please help support this email list: http://www.qsl.net/donate.html <http://www.qsl.net/donate.html>
> Message delivered to [hidden email] <mailto:[hidden email]>

Lew Phelps N6LEW
Pasadena, CA DM04wd
Elecraft K3-10 / KXV144 / XV432
Yaesu FT-7800
[hidden email]
www.n6lew.us

Generalized Law of Entropy: Sooner or later, everything that has been put together will fall apart.





______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

[David Cutter]

Yes, but the weight of water eventually pushes it through - it's cheap but
not perfect. If you use a 20mm fitting as I did back then, water accumulates
inside until a large droplet forms then exits. The Gortex is better but more
$ £.

David, G3UNA


----- Original Message -----
From: "Lewis Phelps" <[hidden email]>
To: <[hidden email]>
Sent: Wednesday, January 20, 2016 8:03 PM
Subject: Re: [Elecraft] Remoting KAT500 to base of antenna

> But might not this re-introduce the surface tension problem?
>
> Lew N6LEW
>
>
>> On Jan 20, 2016, at 10:18 AM, David Cutter <[hidden email]> wrote:
>>
>> From my work in the food industry (if memory serves), critter invasion is
>> prevented with 0.64mm square nylon netting.  This is common in the
>> dress-making industry.  (I think it can also be found as a stainless
>> steel gauze). This can be glued over a breather (drip) hole in the base.
>>
>> David
>> G3UNA
>>
>>
>> ----- Original Message ----- From: "Edward R Cole" <[hidden email]
>> <mailto:[hidden email]>>
>> To: <[hidden email] <mailto:[hidden email]>>
>> Sent: Wednesday, January 20, 2016 8:29 AM
>> Subject: Re: [Elecraft] Remoting KAT500 to base of antenna
>>
>>
>>> Fred,
>>>
>>> Your high desert climate will probably produce less condensation than my
>>> sub-arctic/maritime environ.  What I do for enclosures is to not seal
>>> them airtight but provide good drain openings which air can exchange.
>>> Of course the shelter is made to repel direct rain/snow.
>>>
>>> I suspected that my TR relays were "freezing up" at lower temps making
>>> the action delayed so I used some big aluminum  Dale resistor strapped
>>> onto the relays to add direct heat by conduction.  I happen to have 28v
>>> equipment so used 28v thru the resistors to produce heat within their
>>> wattage rating (used 40w resistors at both relays).  Of course this also
>>> provided some heating of the ambient air of the enclosure which helped
>>> keep moisture from forming even in 90% humidity of the fall.  It rains
>>> 8-days with one day off from August to October when temps finally drop
>>> below freezing and rain becomes snow.  You don't have anything near
>>> that.
>>>
>>> One thing I have noticed about drain holes in some equipment is they are
>>> too small to allow water to drop free due to surface tension and in my
>>> environ that results in the weep holes freezing tight.  I drill them out
>>> to 1/4 inch.  Of course if you are prone to insect/archnid invasion that
>>> is problematic.
>>>
>>> PS: I lived five years in the high Mojave Desert so know all about
>>> "critters of the desert" (never stick your hand into a confined space
>>> before kicking it to see what crawls out or "rattles"!
>>>
>>> 73, Ed - KL7UW
>>> ------------------------------------------
>>>
>>> 3.  Reno/Sparks is a high desert [4,500'] directly adjacent to the
>>> Carson Range and Sierra Nevada [really big mountains].  Winter temps go
>>> down into single digits, it does snow/rain.  Should I do anything to
>>> prevent condensation in the weatherproof box [light bulb, drain hole,
>>> ???].
>>>
>>> 73,
>>>
>>> Fred K6DGW
>>> - Northern California Contest Club
>>> - CU in the Cal QSO Party 1-2 Oct 2016
>>> - www.cqp.org
>>>
>>>
>>> 73, Ed - KL7UW
>>> http://www.kl7uw.com
>>>    "Kits made by KL7UW"
>>> Dubus Mag business:
>>>    [hidden email]
>>>
>>> ______________________________________________________________
>>> Elecraft mailing list
>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>> Help: http://mailman.qth.net/mmfaq.htm
>>> Post: mailto:[hidden email]
>>>
>>> This list hosted by: http://www.qsl.net
>>> Please help support this email list: http://www.qsl.net/donate.html
>>> Message delivered to [hidden email]
>>> <mailto:[hidden email]>
>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft 
>> <http://mailman.qth.net/mailman/listinfo/elecraft>
>> Help: http://mailman.qth.net/mmfaq.htm <http://mailman.qth.net/mmfaq.htm>
>> Post: mailto:[hidden email] <mailto:[hidden email]>
>>
>> This list hosted by: http://www.qsl.net <http://www.qsl.net/>
>> Please help support this email list: http://www.qsl.net/donate.html 
>> <http://www.qsl.net/donate.html>
>> Message delivered to [hidden email] <mailto:[hidden email]>
> Lew Phelps N6LEW
> Pasadena, CA DM04wd
> Elecraft K3-10 / KXV144 / XV432
> Yaesu FT-7800
> [hidden email]
> www.n6lew.us
>
> Generalized Law of Entropy: Sooner or later, everything that has been put
> together will fall apart.
>
>
>
>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

[gm3sek]

The key point about a semi-permeable vent is that it blocks liquid water
(and insects) from getting into the enclosure, but *always* allows water
vapor to escape.  As David points out, plain mesh won't do that under
all conditions.

In the UK, an equivalent to the Gore-Tex engineered vents is available
from Farnell for about £5 ($7.50). Part numbers 2308394 (black) or
2308395 (grey).

CPC normally has them a little cheaper (part numbers EN83188 or EN83189)
but they are currently out of stock.

Compared with the value of the KAT500 inside the enclosure, a properly
engineered semi-permeable vent is a very good investment.


73 from Ian GM3SEK


>-----Original Message-----
>From: Elecraft [mailto:[hidden email]] On Behalf Of
>David Cutter
>Sent: 21 January 2016 07:08
>To: Lewis Phelps; [hidden email]
>Subject: Re: [Elecraft] Remoting KAT500 to base of antenna
>
>Yes, but the weight of water eventually pushes it through - it's cheap
but
>not perfect. If you use a 20mm fitting as I did back then, water
accumulates
>inside until a large droplet forms then exits. The Gortex is better but
more

>$ £.
>
>David, G3UNA
>
>
>----- Original Message -----
>From: "Lewis Phelps" <[hidden email]>
>To: <[hidden email]>
>Sent: Wednesday, January 20, 2016 8:03 PM
>Subject: Re: [Elecraft] Remoting KAT500 to base of antenna
>
>
>> But might not this re-introduce the surface tension problem?
>>
>> Lew N6LEW
>>
>>
>>> On Jan 20, 2016, at 10:18 AM, David Cutter <[hidden email]>
>wrote:
>>>
>>> From my work in the food industry (if memory serves), critter

invasion is
>>> prevented with 0.64mm square nylon netting.  This is common in the
>>> dress-making industry.  (I think it can also be found as a stainless
>>> steel gauze). This can be glued over a breather (drip) hole in the
base.
>>>
>>> David
>>> G3UNA
>>>
>>>
>>> ----- Original Message ----- From: "Edward R Cole"
<[hidden email]
>>> <mailto:[hidden email]>>
>>> To: <[hidden email] <mailto:[hidden email]>>
>>> Sent: Wednesday, January 20, 2016 8:29 AM
>>> Subject: Re: [Elecraft] Remoting KAT500 to base of antenna
>>>
>>>
>>>> Fred,
>>>>
>>>> Your high desert climate will probably produce less condensation
than
>my
>>>> sub-arctic/maritime environ.  What I do for enclosures is to not
seal
>>>> them airtight but provide good drain openings which air can
exchange.
>>>> Of course the shelter is made to repel direct rain/snow.
>>>>
>>>> I suspected that my TR relays were "freezing up" at lower temps
making
>>>> the action delayed so I used some big aluminum  Dale resistor
strapped
>>>> onto the relays to add direct heat by conduction.  I happen to have
28v
>>>> equipment so used 28v thru the resistors to produce heat within
their
>>>> wattage rating (used 40w resistors at both relays).  Of course this
also
>>>> provided some heating of the ambient air of the enclosure which
helped
>>>> keep moisture from forming even in 90% humidity of the fall.  It
rains
>>>> 8-days with one day off from August to October when temps finally
>drop
>>>> below freezing and rain becomes snow.  You don't have anything near
>>>> that.
>>>>
>>>> One thing I have noticed about drain holes in some equipment is
they
>are
>>>> too small to allow water to drop free due to surface tension and in
my
>>>> environ that results in the weep holes freezing tight.  I drill
them out
>>>> to 1/4 inch.  Of course if you are prone to insect/archnid invasion
that
>>>> is problematic.
>>>>
>>>> PS: I lived five years in the high Mojave Desert so know all about
>>>> "critters of the desert" (never stick your hand into a confined
space
>>>> before kicking it to see what crawls out or "rattles"!
>>>>
>>>> 73, Ed - KL7UW
>>>> ------------------------------------------
>>>>
>>>> 3.  Reno/Sparks is a high desert [4,500'] directly adjacent to the
>>>> Carson Range and Sierra Nevada [really big mountains].  Winter
temps
>go
>>>> down into single digits, it does snow/rain.  Should I do anything
to
>>>> prevent condensation in the weatherproof box [light bulb, drain
hole,

>>>> ???].
>>>>
>>>> 73,
>>>>
>>>> Fred K6DGW
>>>> - Northern California Contest Club
>>>> - CU in the Cal QSO Party 1-2 Oct 2016
>>>> - www.cqp.org
>>>>
>>>>
>>>> 73, Ed - KL7UW
>>>> http://www.kl7uw.com
>>>>    "Kits made by KL7UW"
>>>> Dubus Mag business:
>>>>    [hidden email]
>>>>
>>>>
>______________________________________________________________
>>>> Elecraft mailing list
>>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>>> Help: http://mailman.qth.net/mmfaq.htm
>>>> Post: mailto:[hidden email]
>>>>
>>>> This list hosted by: http://www.qsl.net
>>>> Please help support this email list: http://www.qsl.net/donate.html
>>>> Message delivered to [hidden email]
>>>> <mailto:[hidden email]>
>>>
>>>
>______________________________________________________________
>>> Elecraft mailing list
>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>> <http://mailman.qth.net/mailman/listinfo/elecraft>
>>> Help: http://mailman.qth.net/mmfaq.htm
><http://mailman.qth.net/mmfaq.htm>
>>> Post: mailto:[hidden email]
><mailto:[hidden email]>
>>>
>>> This list hosted by: http://www.qsl.net <http://www.qsl.net/>
>>> Please help support this email list: http://www.qsl.net/donate.html
>>> <http://www.qsl.net/donate.html>
>>> Message delivered to [hidden email] <mailto:[hidden email]>
>> Lew Phelps N6LEW
>> Pasadena, CA DM04wd
>> Elecraft K3-10 / KXV144 / XV432
>> Yaesu FT-7800
>> [hidden email]
>> www.n6lew.us
>>
>> Generalized Law of Entropy: Sooner or later, everything that has been

put

>> together will fall apart.
>>
>>
>>
>>
>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to [hidden email]
>
>______________________________________________________________
>Elecraft mailing list
>Home: http://mailman.qth.net/mailman/listinfo/elecraft
>Help: http://mailman.qth.net/mmfaq.htm
>Post: mailto:[hidden email]
>
>This list hosted by: http://www.qsl.net
>Please help support this email list: http://www.qsl.net/donate.html
>Message delivered to [hidden email]

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

[Clay Autery]

Right...  THAT is how you have to look at it when you are
engineering/buying an enclosure.  NOT just at the acquisition costs, but
that you are preventing the loss of many hundreds or thousands of
dollars in equipment AND accomplishing the mission at the same time.

73,

______________________
Clay Autery

On 1/21/2016 1:39 AM, Ian White wrote:
> Compared with the value of the KAT500 inside the enclosure, a properly
> engineered semi-permeable vent is a very good investment.

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

[GM4JJJ]

Just a wee note about the fitting of those nice Gore vents. It is important to have a suitably sized vent or vents for the volume of box and the type of equipment inside it, and Gore can calculate that for you.

For a simple small box for a masthead preamp it is OK to just choose one of the eBay or Farnell/CPC ones that you can buy in one off quantities, but for a larger enclosure with a big investment you want to do it right and the manufacturers will be happy to oblige. I went through Gore in the UK to get my info, and they even sent me free samples as their minimum order was for 100 off.

Unlike drain holes which would be in the bottom of the box, Gore vents are mounted on the vertical wall of the box.



73 from David GM4JJJ

> On 21 Jan 2016, at 15:47, Clay Autery <[hidden email]> wrote:
>
> Right...  THAT is how you have to look at it when you are
> engineering/buying an enclosure.  NOT just at the acquisition costs, but
> that you are preventing the loss of many hundreds or thousands of
> dollars in equipment AND accomplishing the mission at the same time.
>
> 73,
>
> ______________________
> Clay Autery
>
>> On 1/21/2016 1:39 AM, Ian White wrote:
>> Compared with the value of the KAT500 inside the enclosure, a properly
>> engineered semi-permeable vent is a very good investment.
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

[GM4JJJ]

Dear Walter,

Please see Gore's website where this is all explained.

http://www.gore.com/en_xx/products/venting/protective/index.html

It is the way professionals do this, they don't use bits of gauze, wicks made from shoe laces or any of the other amateur solutions seen ;-)


73 from David GM4JJJ

> On 21 Jan 2016, at 15:48, Walter Underwood <[hidden email]> wrote:
>
> Gore-Tex might let moisture out, but it might let it in. Moisture migrates from the more humid side of the membrane to the less humid side. It is a pretty slow process.
>
> wunder
> K6WRU
> Walter Underwood
> CM87wj
> http://observer.wunderwood.org/ (my blog)
>
>> On Jan 20, 2016, at 11:39 PM, Ian White <[hidden email]> wrote:
>>
>> The key point about a semi-permeable vent is that it blocks liquid water
>> (and insects) from getting into the enclosure, but *always* allows water
>> vapor to escape.  As David points out, plain mesh won't do that under
>> all conditions.
>>
>> In the UK, an equivalent to the Gore-Tex engineered vents is available
>> from Farnell for about £5 ($7.50). Part numbers 2308394 (black) or
>> 2308395 (grey).
>>
>> CPC normally has them a little cheaper (part numbers EN83188 or EN83189)
>> but they are currently out of stock.
>>
>> Compared with the value of the KAT500 inside the enclosure, a properly
>> engineered semi-permeable vent is a very good investment.
>>
>>
>> 73 from Ian GM3SEK
>>
>>
>>> -----Original Message-----
>>> From: Elecraft [mailto:[hidden email]] On Behalf Of
>>> David Cutter
>>> Sent: 21 January 2016 07:08
>>> To: Lewis Phelps; [hidden email]
>>> Subject: Re: [Elecraft] Remoting KAT500 to base of antenna
>>>
>>> Yes, but the weight of water eventually pushes it through - it's cheap
>> but
>>> not perfect. If you use a 20mm fitting as I did back then, water
>> accumulates
>>> inside until a large droplet forms then exits. The Gortex is better but
>> more
>>> $ £.
>>>
>>> David, G3UNA
>>>
>>>
>>> ----- Original Message -----
>>> From: "Lewis Phelps" <[hidden email]>
>>> To: <[hidden email]>
>>> Sent: Wednesday, January 20, 2016 8:03 PM
>>> Subject: Re: [Elecraft] Remoting KAT500 to base of antenna
>>>
>>>
>>>> But might not this re-introduce the surface tension problem?
>>>>
>>>> Lew N6LEW
>>>>
>>>>
>>>>> On Jan 20, 2016, at 10:18 AM, David Cutter <[hidden email]>
>>> wrote:
>>>>>
>>>>> From my work in the food industry (if memory serves), critter
>> invasion is
>>>>> prevented with 0.64mm square nylon netting.  This is common in the
>>>>> dress-making industry.  (I think it can also be found as a stainless
>>>>> steel gauze). This can be glued over a breather (drip) hole in the
>> base.
>>>>>
>>>>> David
>>>>> G3UNA
>>>>>
>>>>>
>>>>> ----- Original Message ----- From: "Edward R Cole"
>> <[hidden email]
>>>>> <mailto:[hidden email]>>
>>>>> To: <[hidden email] <mailto:[hidden email]>>
>>>>> Sent: Wednesday, January 20, 2016 8:29 AM
>>>>> Subject: Re: [Elecraft] Remoting KAT500 to base of antenna
>>>>>
>>>>>
>>>>>> Fred,
>>>>>>
>>>>>> Your high desert climate will probably produce less condensation
>> than
>>> my
>>>>>> sub-arctic/maritime environ.  What I do for enclosures is to not
>> seal
>>>>>> them airtight but provide good drain openings which air can
>> exchange.
>>>>>> Of course the shelter is made to repel direct rain/snow.
>>>>>>
>>>>>> I suspected that my TR relays were "freezing up" at lower temps
>> making
>>>>>> the action delayed so I used some big aluminum  Dale resistor
>> strapped
>>>>>> onto the relays to add direct heat by conduction.  I happen to have
>> 28v
>>>>>> equipment so used 28v thru the resistors to produce heat within
>> their
>>>>>> wattage rating (used 40w resistors at both relays).  Of course this
>> also
>>>>>> provided some heating of the ambient air of the enclosure which
>> helped
>>>>>> keep moisture from forming even in 90% humidity of the fall.  It
>> rains
>>>>>> 8-days with one day off from August to October when temps finally
>>> drop
>>>>>> below freezing and rain becomes snow.  You don't have anything near
>>>>>> that.
>>>>>>
>>>>>> One thing I have noticed about drain holes in some equipment is
>> they
>>> are
>>>>>> too small to allow water to drop free due to surface tension and in
>> my
>>>>>> environ that results in the weep holes freezing tight.  I drill
>> them out
>>>>>> to 1/4 inch.  Of course if you are prone to insect/archnid invasion
>> that
>>>>>> is problematic.
>>>>>>
>>>>>> PS: I lived five years in the high Mojave Desert so know all about
>>>>>> "critters of the desert" (never stick your hand into a confined
>> space
>>>>>> before kicking it to see what crawls out or "rattles"!
>>>>>>
>>>>>> 73, Ed - KL7UW
>>>>>> ------------------------------------------
>>>>>>
>>>>>> 3.  Reno/Sparks is a high desert [4,500'] directly adjacent to the
>>>>>> Carson Range and Sierra Nevada [really big mountains].  Winter
>> temps
>>> go
>>>>>> down into single digits, it does snow/rain.  Should I do anything
>> to
>>>>>> prevent condensation in the weatherproof box [light bulb, drain
>> hole,
>>>>>> ???].
>>>>>>
>>>>>> 73,
>>>>>>
>>>>>> Fred K6DGW
>>>>>> - Northern California Contest Club
>>>>>> - CU in the Cal QSO Party 1-2 Oct 2016
>>>>>> - www.cqp.org
>>>>>>
>>>>>>
>>>>>> 73, Ed - KL7UW
>>>>>> http://www.kl7uw.com
>>>>>>  "Kits made by KL7UW"
>>>>>> Dubus Mag business:
>>>>>>  [hidden email]
>>> ______________________________________________________________
>>>>>> Elecraft mailing list
>>>>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>>>>> Help: http://mailman.qth.net/mmfaq.htm
>>>>>> Post: mailto:[hidden email]
>>>>>>
>>>>>> This list hosted by: http://www.qsl.net
>>>>>> Please help support this email list: http://www.qsl.net/donate.html
>>>>>> Message delivered to [hidden email]
>>>>>> <mailto:[hidden email]>
>>> ______________________________________________________________
>>>>> Elecraft mailing list
>>>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>>>> <http://mailman.qth.net/mailman/listinfo/elecraft>
>>>>> Help: http://mailman.qth.net/mmfaq.htm
>>> <http://mailman.qth.net/mmfaq.htm>
>>>>> Post: mailto:[hidden email]
>>> <mailto:[hidden email]>
>>>>>
>>>>> This list hosted by: http://www.qsl.net <http://www.qsl.net/>
>>>>> Please help support this email list: http://www.qsl.net/donate.html
>>>>> <http://www.qsl.net/donate.html>
>>>>> Message delivered to [hidden email] <mailto:[hidden email]>
>>>> Lew Phelps N6LEW
>>>> Pasadena, CA DM04wd
>>>> Elecraft K3-10 / KXV144 / XV432
>>>> Yaesu FT-7800
>>>> [hidden email]
>>>> www.n6lew.us
>>>>
>>>> Generalized Law of Entropy: Sooner or later, everything that has been
>> put
>>>> together will fall apart.
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> ______________________________________________________________
>>>> Elecraft mailing list
>>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>>> Help: http://mailman.qth.net/mmfaq.htm
>>>> Post: mailto:[hidden email]
>>>>
>>>> This list hosted by: http://www.qsl.net
>>>> Please help support this email list: http://www.qsl.net/donate.html
>>>> Message delivered to [hidden email]
>>>
>>> ______________________________________________________________
>>> Elecraft mailing list
>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>> Help: http://mailman.qth.net/mmfaq.htm
>>> Post: mailto:[hidden email]
>>>
>>> This list hosted by: http://www.qsl.net
>>> Please help support this email list: http://www.qsl.net/donate.html
>>> Message delivered to [hidden email]
>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to [hidden email]
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

[GM4JJJ]

Dear Walter,

It isn't -all- it does really - because without the vent the problem is that the water vapour that gets in due to diurnal temperature pressure differentials cannot get back out and then continues to build up inside and forms liquid water inside your lovely expensive box. Other solutions like drain holes have problems with blockage and insect ingress.

Further, it is normal to conformal coat the delicate the electronic PEC's to protect it from condensation you will still get, but equalising pressure with a breathable vent will stop that from becoming a pool of water. If you need more protection than this then you need to have a heater as well, possibly with a fan to assist with ventilation. It all depends on how much you have to protect from the damaging effects of water. The cost of these vents is tiny in comparison.

I only mentioned Gore because that is one of the best know manufacturers of such membrane vents, but there are many others of a similar type and appearance. We all know of Gore-Tex breathable fabrics used in outdoor wear and how well they work. They all work on the same principle.


73 from David GM4JJJ

> On 21 Jan 2016, at 17:07, Walter Underwood <[hidden email]> wrote:
>
> I have no doubt that the Gore solutions work well. But Gore does have an amazing hype machine, and has encouraged people to believe that putting a plastic membrane in clothing does something magic. The Gore vents will make sure that the inside of the box is about as humid as the air outside the box. That’s all.
>
> wunder
> K6WRU
> Walter Underwood
> CM87wj
> http://observer.wunderwood.org/ (my blog)
>
>> On Jan 21, 2016, at 8:04 AM, David Anderson <[hidden email]> wrote:
>>
>> Dear Walter,
>>
>> Please see Gore's website where this is all explained.
>>
>> http://www.gore.com/en_xx/products/venting/protective/index.html
>>
>> It is the way professionals do this, they don't use bits of gauze, wicks made from shoe laces or any of the other amateur solutions seen ;-)
>>
>>
>> 73 from David GM4JJJ
>>
>>> On 21 Jan 2016, at 15:48, Walter Underwood <[hidden email]> wrote:
>>>
>>> Gore-Tex might let moisture out, but it might let it in. Moisture migrates from the more humid side of the membrane to the less humid side. It is a pretty slow process.
>>>
>>> wunder
>>> K6WRU
>>> Walter Underwood
>>> CM87wj
>>> http://observer.wunderwood.org/ (my blog)
>>>
>>>> On Jan 20, 2016, at 11:39 PM, Ian White <[hidden email]> wrote:
>>>>
>>>> The key point about a semi-permeable vent is that it blocks liquid water
>>>> (and insects) from getting into the enclosure, but *always* allows water
>>>> vapor to escape.  As David points out, plain mesh won't do that under
>>>> all conditions.
>>>>
>>>> In the UK, an equivalent to the Gore-Tex engineered vents is available
>>>> from Farnell for about £5 ($7.50). Part numbers 2308394 (black) or
>>>> 2308395 (grey).
>>>>
>>>> CPC normally has them a little cheaper (part numbers EN83188 or EN83189)
>>>> but they are currently out of stock.
>>>>
>>>> Compared with the value of the KAT500 inside the enclosure, a properly
>>>> engineered semi-permeable vent is a very good investment.
>>>>
>>>>
>>>> 73 from Ian GM3SEK
>>>>
>>>>
>>>>> -----Original Message-----
>>>>> From: Elecraft [mailto:[hidden email]] On Behalf Of
>>>>> David Cutter
>>>>> Sent: 21 January 2016 07:08
>>>>> To: Lewis Phelps; [hidden email]
>>>>> Subject: Re: [Elecraft] Remoting KAT500 to base of antenna
>>>>>
>>>>> Yes, but the weight of water eventually pushes it through - it's cheap
>>>> but
>>>>> not perfect. If you use a 20mm fitting as I did back then, water
>>>> accumulates
>>>>> inside until a large droplet forms then exits. The Gortex is better but
>>>> more
>>>>> $ £.
>>>>>
>>>>> David, G3UNA
>>>>>
>>>>>
>>>>> ----- Original Message -----
>>>>> From: "Lewis Phelps" <[hidden email]>
>>>>> To: <[hidden email]>
>>>>> Sent: Wednesday, January 20, 2016 8:03 PM
>>>>> Subject: Re: [Elecraft] Remoting KAT500 to base of antenna
>>>>>
>>>>>
>>>>>> But might not this re-introduce the surface tension problem?
>>>>>>
>>>>>> Lew N6LEW
>>>>>>
>>>>>>
>>>>>>> On Jan 20, 2016, at 10:18 AM, David Cutter <[hidden email]>
>>>>> wrote:
>>>>>>>
>>>>>>> From my work in the food industry (if memory serves), critter
>>>> invasion is
>>>>>>> prevented with 0.64mm square nylon netting.  This is common in the
>>>>>>> dress-making industry.  (I think it can also be found as a stainless
>>>>>>> steel gauze). This can be glued over a breather (drip) hole in the
>>>> base.
>>>>>>>
>>>>>>> David
>>>>>>> G3UNA
>>>>>>>
>>>>>>>
>>>>>>> ----- Original Message ----- From: "Edward R Cole"
>>>> <[hidden email]
>>>>>>> <mailto:[hidden email]>>
>>>>>>> To: <[hidden email] <mailto:[hidden email]>>
>>>>>>> Sent: Wednesday, January 20, 2016 8:29 AM
>>>>>>> Subject: Re: [Elecraft] Remoting KAT500 to base of antenna
>>>>>>>
>>>>>>>
>>>>>>>> Fred,
>>>>>>>>
>>>>>>>> Your high desert climate will probably produce less condensation
>>>> than
>>>>> my
>>>>>>>> sub-arctic/maritime environ.  What I do for enclosures is to not
>>>> seal
>>>>>>>> them airtight but provide good drain openings which air can
>>>> exchange.
>>>>>>>> Of course the shelter is made to repel direct rain/snow.
>>>>>>>>
>>>>>>>> I suspected that my TR relays were "freezing up" at lower temps
>>>> making
>>>>>>>> the action delayed so I used some big aluminum  Dale resistor
>>>> strapped
>>>>>>>> onto the relays to add direct heat by conduction.  I happen to have
>>>> 28v
>>>>>>>> equipment so used 28v thru the resistors to produce heat within
>>>> their
>>>>>>>> wattage rating (used 40w resistors at both relays).  Of course this
>>>> also
>>>>>>>> provided some heating of the ambient air of the enclosure which
>>>> helped
>>>>>>>> keep moisture from forming even in 90% humidity of the fall.  It
>>>> rains
>>>>>>>> 8-days with one day off from August to October when temps finally
>>>>> drop
>>>>>>>> below freezing and rain becomes snow.  You don't have anything near
>>>>>>>> that.
>>>>>>>>
>>>>>>>> One thing I have noticed about drain holes in some equipment is
>>>> they
>>>>> are
>>>>>>>> too small to allow water to drop free due to surface tension and in
>>>> my
>>>>>>>> environ that results in the weep holes freezing tight.  I drill
>>>> them out
>>>>>>>> to 1/4 inch.  Of course if you are prone to insect/archnid invasion
>>>> that
>>>>>>>> is problematic.
>>>>>>>>
>>>>>>>> PS: I lived five years in the high Mojave Desert so know all about
>>>>>>>> "critters of the desert" (never stick your hand into a confined
>>>> space
>>>>>>>> before kicking it to see what crawls out or "rattles"!
>>>>>>>>
>>>>>>>> 73, Ed - KL7UW
>>>>>>>> ------------------------------------------
>>>>>>>>
>>>>>>>> 3.  Reno/Sparks is a high desert [4,500'] directly adjacent to the
>>>>>>>> Carson Range and Sierra Nevada [really big mountains].  Winter
>>>> temps
>>>>> go
>>>>>>>> down into single digits, it does snow/rain.  Should I do anything
>>>> to
>>>>>>>> prevent condensation in the weatherproof box [light bulb, drain
>>>> hole,
>>>>>>>> ???].
>>>>>>>>
>>>>>>>> 73,
>>>>>>>>
>>>>>>>> Fred K6DGW
>>>>>>>> - Northern California Contest Club
>>>>>>>> - CU in the Cal QSO Party 1-2 Oct 2016
>>>>>>>> - www.cqp.org
>>>>>>>>
>>>>>>>>
>>>>>>>> 73, Ed - KL7UW
>>>>>>>> http://www.kl7uw.com
>>>>>>>> "Kits made by KL7UW"
>>>>>>>> Dubus Mag business:
>>>>>>>> [hidden email]
>>>>> ______________________________________________________________
>>>>>>>> Elecraft mailing list
>>>>>>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>>>>>>> Help: http://mailman.qth.net/mmfaq.htm
>>>>>>>> Post: mailto:[hidden email]
>>>>>>>>
>>>>>>>> This list hosted by: http://www.qsl.net
>>>>>>>> Please help support this email list: http://www.qsl.net/donate.html
>>>>>>>> Message delivered to [hidden email]
>>>>>>>> <mailto:[hidden email]>
>>>>> ______________________________________________________________
>>>>>>> Elecraft mailing list
>>>>>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>>>>>> <http://mailman.qth.net/mailman/listinfo/elecraft>
>>>>>>> Help: http://mailman.qth.net/mmfaq.htm
>>>>> <http://mailman.qth.net/mmfaq.htm>
>>>>>>> Post: mailto:[hidden email]
>>>>> <mailto:[hidden email]>
>>>>>>>
>>>>>>> This list hosted by: http://www.qsl.net <http://www.qsl.net/>
>>>>>>> Please help support this email list: http://www.qsl.net/donate.html
>>>>>>> <http://www.qsl.net/donate.html>
>>>>>>> Message delivered to [hidden email] <mailto:[hidden email]>
>>>>>> Lew Phelps N6LEW
>>>>>> Pasadena, CA DM04wd
>>>>>> Elecraft K3-10 / KXV144 / XV432
>>>>>> Yaesu FT-7800
>>>>>> [hidden email]
>>>>>> www.n6lew.us
>>>>>>
>>>>>> Generalized Law of Entropy: Sooner or later, everything that has been
>>>> put
>>>>>> together will fall apart.
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> ______________________________________________________________
>>>>>> Elecraft mailing list
>>>>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>>>>> Help: http://mailman.qth.net/mmfaq.htm
>>>>>> Post: mailto:[hidden email]
>>>>>>
>>>>>> This list hosted by: http://www.qsl.net
>>>>>> Please help support this email list: http://www.qsl.net/donate.html
>>>>>> Message delivered to [hidden email]
>>>>>
>>>>> ______________________________________________________________
>>>>> Elecraft mailing list
>>>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>>>> Help: http://mailman.qth.net/mmfaq.htm
>>>>> Post: mailto:[hidden email]
>>>>>
>>>>> This list hosted by: http://www.qsl.net
>>>>> Please help support this email list: http://www.qsl.net/donate.html
>>>>> Message delivered to [hidden email]
>>>>
>>>> ______________________________________________________________
>>>> Elecraft mailing list
>>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>>> Help: http://mailman.qth.net/mmfaq.htm
>>>> Post: mailto:[hidden email]
>>>>
>>>> This list hosted by: http://www.qsl.net
>>>> Please help support this email list: http://www.qsl.net/donate.html
>>>> Message delivered to [hidden email]
>>>
>>> ______________________________________________________________
>>> Elecraft mailing list
>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>> Help: http://mailman.qth.net/mmfaq.htm
>>> Post: mailto:[hidden email]
>>>
>>> This list hosted by: http://www.qsl.net
>>> Please help support this email list: http://www.qsl.net/donate.html
>>> Message delivered to [hidden email]
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

[Edward R Cole]

At the risk of repeating myself, I do not use any mesh covering vent
holes on enclosures that are above ground level (at least a few
feet).  I've not had any intrusion of "critters" and we have wasp
nests which seem to prefer underside of roof eves. I'm guessing the
wildlife have plenty of alternative "homes" here at the edge of
wilderness to bother with RF exposure! ;-)

I used ordinary window screen material in the bottom 4-inch diameter
vent holes of my PS enclosure at my dish as the fans draw air into
the box from a plenum area below and that is definitely spider and
bug haven.  Exhaust vent is similarly screened.
http://www.kl7uw.com/DishPS_11.jpg
http://www.kl7uw.com/DishPS_09.jpg
http://www.kl7uw.com/DishPS_02.jpg
http://www.kl7uw.com/DishPS_03.jpg

In my amplifier boxes fans move air thru vents and heated air from
high power equipment keeps condensation free in the interior if I run
equipment often enough.  I do use stainless steel hardware which
inhibits corrosion.

I have two Hoffman style boxes at the dish and three on the 2m-eme
tower Hazer.  Except for the 2m-eme preamp/relay box all have
amplifiers providing air heating.
http://www.kl7uw.com/1296PA_enclosure_1.jpg
http://www.kl7uw.com/2m-eme%20lowered.jpg

73, Ed - KL7UW
http://www.kl7uw.com
     "Kits made by KL7UW"
Dubus Mag business:
     [hidden email]

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]