(I realize that a through-the-glass antenna is less than ideal.
Nevertheless, that's what I have to use in my situation.) The one I
have is for 2 meters (NOT dual band), and the label says up to 50
watts. I have an Icom IC-2200H, which has a maximum of 65 watts
output.

What bad things may/could/will happen if I put 65 watts through the
antenna?

Thanks!

Tom Mitchell -- KG7U
Port Angeles, Washington. USA
--------------------------------------------------------------------------
Tom Mitchell, Port Angeles, Washington, USA
http://www.olympus.net/personal/kg7u
--------------------------------------------------------------------------

"Thomas & Karen Mitchell" kg7uATolympus.net wrote in message
...
(I realize that a through-the-glass antenna is less than ideal.
Nevertheless, that's what I have to use in my situation.) The one I
have is for 2 meters (NOT dual band), and the label says up to 50
watts. I have an Icom IC-2200H, which has a maximum of 65 watts
output.

What bad things may/could/will happen if I put 65 watts through the
antenna?

Thanks!

Tom Mitchell -- KG7U
Port Angeles, Washington. USA
--------------------------------------------------------------------------
Tom Mitchell, Port Angeles, Washington, USA
http://www.olympus.net/personal/kg7u
--------------------------------------------------------------------------

Tom

Through glass antennas work using capacitance. The two plates either side of
the glass form the capacitance with the glass acting as the insulator.
Attempting to put too much power through a capacitor usually results in
overheating or a breakdown of the insulator. This could potentially result
in a broken screen.

Another thing to consider is the mismatch that the through glass capacitor
makes with your transmitter. Some of the power will inevitably be reflected
back to the output stages causing possible overheating at full power.

I would guess that 65 watts would be safe enough for brief transmissions but
for longer chats keep the power down below 50 watts. For mobile use, the
difference in signal strength, a fraction of an S-point, is unlikely to be
noticed by anyone receiving your signal.

Mike G0ULI

"Mike Kaliski" wrote in message
...

"Thomas & Karen Mitchell" kg7uATolympus.net wrote in message
...
(I realize that a through-the-glass antenna is less than ideal.
Nevertheless, that's what I have to use in my situation.) The one I
have is for 2 meters (NOT dual band), and the label says up to 50
watts. I have an Icom IC-2200H, which has a maximum of 65 watts
output.

What bad things may/could/will happen if I put 65 watts through the
antenna?

Thanks!

Tom Mitchell -- KG7U
Port Angeles, Washington. USA
--------------------------------------------------------------------------
Tom Mitchell, Port Angeles, Washington, USA
http://www.olympus.net/personal/kg7u
--------------------------------------------------------------------------

Tom

Through glass antennas work using capacitance. The two plates either side
of
the glass form the capacitance with the glass acting as the insulator.
Attempting to put too much power through a capacitor usually results in
overheating or a breakdown of the insulator. This could potentially result
in a broken screen.

Another thing to consider is the mismatch that the through glass capacitor
makes with your transmitter. Some of the power will inevitably be
reflected
back to the output stages causing possible overheating at full power.

I would guess that 65 watts would be safe enough for brief transmissions
but
for longer chats keep the power down below 50 watts. For mobile use, the
difference in signal strength, a fraction of an S-point, is unlikely to be
noticed by anyone receiving your signal.

Mike G0ULI



My friend has a 71 Dodge Charger, He used one because he didnt want to drill
any holes in this classic muscle car. He made the mistake of running about
200 wats to the antenna and it caused the plastic sheet in the saftey glas
to delaminate.. He has a big white spot on the edge of his rear window now.
I have run one without any damage to the window but I got a lot of picket
fencing with it. Didnt keep it for long.

Unless you are talking about a classic car drilling a hole in the roof
doesnt effect resell valure

Jimmie

Used a 110 watt MASTR 2 mobile through one in 1980s.

What happens after about 2 minutes of talk time -- box heats up and SWR
rises substantially.
When I removed the tuning box a couple years later -- components toasted.

SO, when it says 50 watts maximum -- they mean it.

gb


"Thomas & Karen Mitchell" kg7uATolympus.net wrote in message
...
(I realize that a through-the-glass antenna is less than ideal.
Nevertheless, that's what I have to use in my situation.) The one I
have is for 2 meters (NOT dual band), and the label says up to 50
watts. I have an Icom IC-2200H, which has a maximum of 65 watts
output.

What bad things may/could/will happen if I put 65 watts through the
antenna?

Thanks!

Tom Mitchell -- KG7U
Port Angeles, Washington. USA
--------------------------------------------------------------------------
Tom Mitchell, Port Angeles, Washington, USA
http://www.olympus.net/personal/kg7u
--------------------------------------------------------------------------

Thomas & Karen Mitchell wrote:
(I realize that a through-the-glass antenna is less than ideal.
Nevertheless, that's what I have to use in my situation.) The one I
have is for 2 meters (NOT dual band), and the label says up to 50
watts. I have an Icom IC-2200H, which has a maximum of 65 watts
output.

What bad things may/could/will happen if I put 65 watts through the
antenna?

Thanks!

Tom Mitchell -- KG7U
Port Angeles, Washington. USA
--------------------------------------------------------------------------
Tom Mitchell, Port Angeles, Washington, USA
http://www.olympus.net/personal/kg7u
--------------------------------------------------------------------------


Tom;

The only thing you want to watch out for is to not place the antenna
pads on one of the defrost wires.
I have used one in the past with good success.
Dave WD9BDZ

These are not the most effecient, and depending on
the
glass, you may find that there is some metalic
content in the glass, makeing a perfect match
impossible. Think was a pic, in QST couple months
ago of one (struck by lightning), showed the
fractured glass. But, the difference between
50 and 65 watts is very little in the scheme of
things, Maybe 1 Db. Most likely would make little
difference- the METAL CONTENT of the glass, would
make more difference , as the loss would be heat!
Jim NN7K

Thomas & Karen Mitchell wrote:
(I realize that a through-the-glass antenna is less than ideal.
Nevertheless, that's what I have to use in my situation.) The one I
have is for 2 meters (NOT dual band), and the label says up to 50
watts. I have an Icom IC-2200H, which has a maximum of 65 watts
output.

What bad things may/could/will happen if I put 65 watts through the
antenna?

Thanks!

Tom Mitchell -- KG7U
Port Angeles, Washington. USA
--------------------------------------------------------------------------
Tom Mitchell, Port Angeles, Washington, USA
http://www.olympus.net/personal/kg7u
--------------------------------------------------------------------------

Thanks to one and all. The Icom IC-2200H doesn't have a choice of 50
watts output; it goes from 25 to 65.

So: I'll stay at 25 when in the car.

-- KG7U
--------------------------------------------------------------------------
Tom Mitchell, Port Angeles, Washington, USA
http://www.olympus.net/personal/kg7u
--------------------------------------------------------------------------

Thomas & Karen Mitchell wrote:

...
So: I'll stay at 25 when in the car.

-- KG7U
--------------------------------------------------------------------------
Tom Mitchell, Port Angeles, Washington, USA
http://www.olympus.net/personal/kg7u
--------------------------------------------------------------------------

Every engineer, worth his pay, which I know, allow at least a 20% excess
on ratings.

50 X 20% = 10 watts

50 + 10 = 60 watts

I'd run the 65 and examine the glass mount now and then. You'll see if
damage begins and switch lower power.

Warm regards,
JS

John Smith I wrote:
Thomas & Karen Mitchell wrote:

...

So: I'll stay at 25 when in the car.

-- KG7U
--------------------------------------------------------------------------

Tom Mitchell, Port Angeles, Washington, USA
http://www.olympus.net/personal/kg7u
--------------------------------------------------------------------------



Every engineer, worth his pay, which I know, allow at least a 20% excess
on ratings.

50 X 20% = 10 watts

50 + 10 = 60 watts

I'd run the 65 and examine the glass mount now and then. You'll see if
damage begins and switch lower power.

Warm regards,
JS

Obviously the engineers who established the maximum power
specification would not advocate using greater than 50 watts.

ac6xg

Jim Kelley wrote:

...
Obviously the engineers who established the maximum power specification
would not advocate using greater than 50 watts.

ac6xg

1) No engineer would advocate over-clocking computers the way I do.
2) No engineer would advocate pushing rigs and liners (power amps) to
the limits I do.
3) No engineer would advocate doing the mods to equipment I do.
4) No engineer would advocate the antenna experiments I carry out.
6) No engineer would advocate the engine mods to my vette which I have done.
7) No engineer would advocate the levels of exposure to RF I expose
myself too.
8) ...

That's what makes it fun, now doesn't it?

JS