On Mon, 11 Apr 2005 09:08:54 -0700, Richard Clark
wrote:

On Mon, 11 Apr 2005 09:48:17 -0500, Tom Ring
wrote:

HP416A.

Hi Tom,

By description and application, probably, but I need a picture or
manual to be able to confirm. I've calibrated and used so much
different gear that the numbers blur.


http://www.qsl.net/n7ws/HP416.pdf

The (inappropriately named) Pacific coast where Danny lives has
fair-sized waves almost constantly, particularly in the winter. When
they break along the shore, a very fine mist of salt water droplets is
created, and those drift for a long distance. In the winter, the
prevailing wind direction is from the west, so the salt water mist is
blown farther yet. The result is that the air itself contains a
suspension of salt water. Aluminum corrodes fairly quickly, and good
sized bare copper wire turns into a blue powder in a year or less. Where
I live, in the Willamette valley of Oregon which is about 70 miles
inland, it rains pretty constantly from about October through June --
not an extraordinary amount, but everything outside stays wet for the
whole winter because of the lack of direct sunshine and the frequent
rain. But aluminum lasts forever and so does copper, which only gets a
thin, dark oxide coating. It's the salt water suspension that's the
killer on the coast.

Roy Lewallen, W7EL

Dan Richardson wrote:
On Sun, 10 Apr 2005 23:58:12 -0400, Mike Coslo
wrote:



How close to the ocean are you? It sounds like you are right in the spray!



About a half mile. I live in the northern California "Mendocino"
coast. We have a lot of rain too and that combination is a killer for
aluminum exposed to the elements.

Danny

On Mon, 11 Apr 2005 10:48:54 -0700, Roy Lewallen
wrote:

It's the salt water suspension that's the
killer on the coast.

Yea, but those launch angles to the west. G

Danny, K6MHE

On Mon, 11 Apr 2005 10:40:56 -0700, Wes Stewart
wrote:

On Mon, 11 Apr 2005 09:08:54 -0700, Richard Clark
wrote:

On Mon, 11 Apr 2005 09:48:17 -0500, Tom Ring
wrote:

HP416A.

Hi Tom,

By description and application, probably, but I need a picture or
manual to be able to confirm. I've calibrated and used so much
different gear that the numbers blur.


http://www.qsl.net/n7ws/HP416.pdf


GAD!

I had forgotten that white elephant. Thanx Wes.

Tom,

It is pretty much in the same class of expanded range, 1KHz tuned AC
Voltmeters. As long as you reference and return to a Cardinal point
on the scale, accuracy you describe can be supported.

In fact, this class of instrumentation is probably the best leverage
to building a very good RF lab. You can spend more, you could even
find equipment that does most of the grunt work for you, but it is
still a long shot that you will obtain more accuracy.

Accuracy is steadfastly bound to method and this style of
instrumentation reveals an example of method thought out and polished
with the best of engineering thought.

73's
Richard Clark, KB7QHC

Richard Clark wrote:
....

I've calibrated these too (Boonton, I think, also built them, but as
Boonton was acquired by HP, it isn't a remarkable difference).


Errrk?? From Boonton's web site:

"In July 2000 we became a member of a larger family as we were acquired
by Wireless Telecom Group, Inc. (doing business as Noise Com). Being a
wholly owned subsidiary of Wireless Telecom Group, Inc. has enabled us
to further our product development and customer service initiatives."

See http://www.boonton.com/2002/about-history.html

Since you're wanting to make it black to match other accouterments on
your vehicle, consider that most, if not all, black-dyed anodization
will fade in the sunlight, and it doesn't take all that long. In
addition, depending on the aluminum alloy, the "black" may not be all
that black to begin with. Why not instead give the antenna a coat of
automotive enamel or lacquer? You can either mask off areas that need
to have electrical contact, or scrape them after painting. Perhaps you
can paint after the antenna is assembled. That way, you can get a
color that really matches other items.

Cheers,
Tom

On 11 Apr 2005 11:52:53 -0700, "K7ITM" wrote:


Richard Clark wrote:
...

I've calibrated these too (Boonton, I think, also built them, but as
Boonton was acquired by HP, it isn't a remarkable difference).


Errrk?? From Boonton's web site:

"In July 2000 we became a member of a larger family as we were acquired
by Wireless Telecom Group, Inc. (doing business as Noise Com). Being a
wholly owned subsidiary of Wireless Telecom Group, Inc. has enabled us
to further our product development and customer service initiatives."

See http://www.boonton.com/2002/about-history.html

They left out part of their history.

H-P *did* acquire Boonton at one time. I have both a black crackle
Boonton 250 RX meter and an H-P gray HP 250 RX meter out in my storage
building.

Once long ago I was driving down highway 101 in my VW squareback,
operating mobile CW late at night on 40 meters. Rig was homebrew, about
8-9 watts output (10 watts input). Antenna was a CB mobile whip on a
bumper mount, base loaded with a coil wound on a powdered iron toroid
core, Q about 200 - 250. Worked JA, solid copy. Yea, that salt water
does wonders for a vertical.

Roy Lewallen, W7EL

Dan Richardson wrote:
On Mon, 11 Apr 2005 10:48:54 -0700, Roy Lewallen
wrote:


It's the salt water suspension that's the
killer on the coast.


Yea, but those launch angles to the west. G

Danny, K6MHE

Thanks Tom (& everybody else). The problem is that I'm planing on
having an 8' two section whip on the top that will power extend &
retract through the loading coil into the bottom mast.

Why?

Call it a combination of lazyness & a prepondarence towards low
ceilings in parking garages. Also (bonus), with the coil retracted
I'll be able to vary the height of the whip for the upper bands.

So what I was really looking (hoping) for is a black coating that
maintains electrical contact between the inner & outer whip sections
as one slides in & out of the other.

Don't look like I'm gonna get it :(.

Maybe it would be easier just to build a test range insted :).

H.

On 11 Apr 2005 12:01:05 -0700, "K7ITM" wrote:

Since you're wanting to make it black to match other accouterments on
your vehicle, consider that most, if not all, black-dyed anodization
will fade in the sunlight, and it doesn't take all that long. In
addition, depending on the aluminum alloy, the "black" may not be all
that black to begin with. Why not instead give the antenna a coat of
automotive enamel or lacquer? You can either mask off areas that need
to have electrical contact, or scrape them after painting. Perhaps you
can paint after the antenna is assembled. That way, you can get a
color that really matches other items.

Cheers,
Tom

On Mon, 11 Apr 2005 06:47:14 -0700, Dan Richardson
wrote:
On Sun, 10 Apr 2005 23:58:12 -0400, Mike Coslo
wrote:

How close to the ocean are you? It sounds like you are right in the spray!

About a half mile. I live in the northern California "Mendocino"
coast. We have a lot of rain too and that combination is a killer for
aluminum exposed to the elements.

Has anyone done any testing (RF resistance) on squirting some NOALOX
compound (or other anti-corrosion sealants) between the aluminum
elements and scrubbing them clean to remove the oxide film before
bolting them together? Should help a lot, especially along the coast.

Works great on AL power wire at 60Hz...

-- Bruce --

(KBPY-8540 - wait, they discontinued those calls. Oh well...) ;-)
--
Bruce L. Bergman, Woodland Hills (Los Angeles) CA - Desktop
Electrician for Westend Electric - CA726700
5737 Kanan Rd. #359, Agoura CA 91301 (818) 889-9545
Spamtrapped address: Remove the python and the invalid, and use a net.