Fur Shur!

"Bruce in Alaska" wrote in message
...
In article ,
"Doug Dotson" wrote:

I prefer a reflected power meter. Much more inruitive than
an SWR meter. Converting from RP to SWR is a simple formula
as well.

Doug, k3qt
s/v Callista

Nothing like a good Bird Wattmeter, fresh out of the Cal Shop,
to see what's going on in an Antenna System.

Bruce in alaska
--
add a 2 before @

Marcus AAkesson wrote:

On Wed, 12 Nov 2003 15:41:08 -0500, "Jim Woodward" jameslwoodward at
attbi dot com wrote:

4) What do you like other than the cheap white crap for antenna cable? I
used Belden 9913 (solid center conductor) on Swee****er. Is that still a
good choice?

RG214 or similar which is silver plated Cu in both conductor and
shield. Raw copper will in time oxidize and deteriorate in the salty
environment. I have seen some really ugly cables after only 5-6 years.


Check out http://www.therfc.com/attenrat.htm

Common RG-58A (the white crap) looses 7.4dB/100 ft at 200MHz. That's
over half your signal used to heat the coax! RG-8X (mini-RG8 - the other
white crap) is almost as bad at 5.4 dB/100'. Belden 9913 is excellent at
only 1.8dB/100. RG-214 has 3.3dB loss/100' but as Marcus suggests may
have better corrosion resistance. Of course if money, size and weight
are unimportant there's LDF5 (c:

Thanks to Marcus for suggesting RG214 and Vito for the numbers. On
Swee****er it was about 110 feet from radio to antenna (82' in the mast,
plus radio to mast), so I worried about losses. The bare copper solid #10
AWG center conductor of 9913 won't corrode much, and the shield is tinned,
so it won't corrode much either.

On Fintry, it's only about 25' from radios to antennas, and the antenna end
is much closer to the sea, so I'll probably use RG214 unless someone has a
better idea. Besides, putting 259s on that #10 wire is a pain.


--
Jim Woodward
www.mvFintry.com


..
"Vito" wrote in message
...
Marcus AAkesson wrote:

On Wed, 12 Nov 2003 15:41:08 -0500, "Jim Woodward" jameslwoodward at
attbi dot com wrote:

4) What do you like other than the cheap white crap for antenna cable?
I
used Belden 9913 (solid center conductor) on Swee****er. Is that still
a
good choice?

RG214 or similar which is silver plated Cu in both conductor and
shield. Raw copper will in time oxidize and deteriorate in the salty
environment. I have seen some really ugly cables after only 5-6 years.


Check out http://www.therfc.com/attenrat.htm

Common RG-58A (the white crap) looses 7.4dB/100 ft at 200MHz. That's
over half your signal used to heat the coax! RG-8X (mini-RG8 - the other
white crap) is almost as bad at 5.4 dB/100'. Belden 9913 is excellent at
only 1.8dB/100. RG-214 has 3.3dB loss/100' but as Marcus suggests may
have better corrosion resistance. Of course if money, size and weight
are unimportant there's LDF5 (c:

In article ,
"Jim Woodward" jameslwoodward at attbi dot com wrote:

Good explanation, thanks. Questions:

1) You suggest the possibility of leaving the meter in the line permanently.
Doesn't the impedance bump of a PL-259 speak against that?

2) Since the meter is not type accepted, is leaving it in permanently
technically an FCC violation?

3) I went to
http://www.wzpxtv.com/wzpxtransmitter.htm
and saw a bunch of readouts. The readout labeled "VSWR" (which I think is
the same thing) was reading 0.80 or 0.70.

4) What do you like other than the cheap white crap for antenna cable? I
used Belden 9913 (solid center conductor) on Swee****er. Is that still a
good choice?



--
Jim Woodward
www.mvFintry.com

1. PL-259's do leave an impedance bump in the line, that's true, but the
significance of that is questionable, as to the effect on Radio
Operation.

2. Only Active Transmitters and Receivers are Type Accepted by the FCC.
Passive components like coax, antennas, power supplys, ect are up to
the licensee to deal with and not subject to FCC as they aren't addressed
in Part 80.

3. Been using 9913 since I did some of the original enviormental
testing for Beldon. I use it darn near everywhere. Just remeber that it
has a Bend Radius of about 8" and if you kink it, you just trashed it.
Connectors for 9913 are a bit different to install, and AMP had to
come out with a new shinch design for their N Type Connectors for 9913.
also if you get a split in the jacket, water can be a real problem
in 9913.

Bruce in alaska
--
add a 2 before @

Larry

That's the best description I've seen, brilliant.
Regards,
Brian

"Larry W4CSC" wrote in message
...
I've seen many posters talk about antennas and know lots of boaters
with antenna troubles and no clue how to see how it's doing, way up
there, so thought I'd stick my neck into the guillotine and give some
basic instructions on what an SWR meter is, what it does, and what it
means after you learn how to use it. This will be all about VHF
marine band, but is the same for any frequency the meter is made for.

FIRST, let me say not all SWR meters are suitable for VHF marine band
use. The reason for this has to do with the directional coupler, the
part that senses power going this way and power going that way built
into your meter. A CB SWR meter is NOT suitable for VHF work. VHF is
out of its design range and its directional coupler is too long. Put
using a CB SWR meter out of your mind. It's not a good reading. A
ham radio VHF SWR meter IS acceptable as its range is usually from 140
to 170 Mhz, which includes our VHF marine band. Most boaters will get
the little white Shakespeare VHF power and SWR meter from Waste Marine
or some other overpricing boat shop so that's what I'll use for my
example.

These little passive SWR meters use the RF power of your radio to
power the meter and require no batteries or power source. One guy I
know got no reading and through the meter had dead batteries in it.
There aren't any. His transmitter power amp was kaput....no output.

THE CONTROLS.

The controls on it are quite simple. There's a switch that switches
from POWER OUTPUT to REFERENCE (SETUP) to SWR, a 3-position slide
switch. The POWER OUTPUT meter is useless unless you have the ANTENNA
jack plugged into a 50 ohm dummy load like the guys at the factory did
to calibrate it. Depending on the position of the meter in the line
of a defective antenna system, it might read way low or it might peg
on 1 watt. Consider it fairly accurate if the SWR of the antenna is
quite low (below 1.5 to 1)

So, What's SWR??.....

SWR (pronounced as three letters, unless you're on CB where it's
called "swur" for some reason noone knows) means Standing Wave Ratio.
The keyword there is RATIO, a measurement of the peak voltage found on
the transmission line in one place, compared to the minimum (trough?)
voltage found 1/4 wavelength from that peak in either direction.
These peaks and valleys are caused by reflections of an imperfect or
off-tuned antenna, bad connectors, kinked transmission lines bent too
sharply and a lot of just poor luck. You can watch these waves out by
the seawall. If you toss a rock into the water (transmitter) it
creates waves that expand out in all directions. When the wave
bounces off the seawall, watch what happens. The wave coming in from
the stone bounce off the REFLECTIVE seawall and go BACK towards the
transmitter, a "reflected power" that wasn't absorbed by the wall. As
the reflected waves pass through the incoming waves that haven't
reflected, yet, notice how there is a wave that doesn't move.....a
Standing Wave that has PEAK positions that stand still a set distance
from TROUGH positions, that also stand still.

The same exact thing is going on in your antenna system, every time
you press that button. In electronics, there are two simple devices
that STORE electrons....capacitors that charge (electrostatically) and
inductors that store energy (magnetically). If you doubt this, go out
and pull the spark plug wire off a running Seagull outboard to test
this theory....we'll wait. Ah, I see you're back? Why do you look so
"shocked"? Did it work?

A perfect RF transmission system perfectly transfers the power from
the transmitter to the perfect antenna, which radiates all the power
the transmitter put out into the air, blasting all the recievers with
your fantastic signal so they can hear your pleas for help. These
systems do not exist. The antenna is never tuned to your channel,
only close to your channel (we hope) and the transmission line is that
cheap white crap from Wasted Marine or RatShack, not rigid coaxial
line used by broadcast stations, made to exacting standards. To keep
it short, the line and antenna have "reactance", like that wall. And
it's that reactance (inductance and capacitance) that cause anomolies
that make reflections, like that wall.

What can we do? How can we measure how bad it is?...............

Most marine antennas are sealed up and "pretuned" for open areas. Not
much we can do to "tune" them to the middle of the band. I like old
Metz antennas, made by an old ham company, just because I can trim
that element for best results. It's tunable. That fishing pole of a
fiberglass antenna is actually a little, specially bent wire embedded
inside fiberglass to keep it straight (and disintegrate reliably in
sunshine so you can replace it, often). "Pruning" the tunable antenna
requires us to measure SWR at different frequencies so we can center
its curve up on the band we want for best results.

What "curve"??

An antenna "resonates", where the inductance balances out the
capacitance and acts like a radiating resistive load, over a fairly
large range of frequencies, not just one. Lucky for us.....it can be
made to pass channel 1 and channel 72, fairly reliably, without
retuning like you have to do to change channels on the HF SSB antenna.
The curve looks kinda like this:
| * *
SWR| * *
| * *
| *
Frequency

If we center the best (lowest) SWR up in the middle of the band, it
will have an acceptable SWR (low) on channels on the bottom and top we
want, and are allowed to use. Part of the testing, we will test
different channels across the marine band to get an idea of what YOUR
plot would look like.

So, how do we measure SWR??.............

For the little meter to measure the antenna, it has to be located
INLINE with the RF power, between the transmitter and antenna.
IDEALLY, we'd like to adjust the antenna with the SWR meter located
between the transmission line, antenna end, and the antenna's coax
connector. Obviously, sometimes, this is not practical for a simple
test. However, the further you are from the antenna, back down the
transmission line, the less the reading is about the antenna SWR and
the more the reading is about the cable losing the signal (attenuation
and leakage) and the reactivity of the cable, itself. If we measure
the SWR at the antenna end, the SWR we measure is only about the
antenna. If we measure it where it's easy, at the radio, the reading
is about the antenna AND the cable, so you can't tell which is at
fault if it sucks.

OK, let's assume you're like me, hate heights, weigh too much to haul
up on a winch with less than 6 strong arms on a winch handle and the
bos'n's chair might not like the load, anyways. So, we'll measure the
antenna at the radio end, at least until we find it's all screwed up.
Disconnect the antenna from the radio, with the radio off so you don't
inadvertently transmit into an open which might do harm to the
transmitter.

Now you need a "coax jumper" that didn't come with the meter. Radio
Shack has them, so get one that's just long enough to hook the meter's
RADIO port to the radio so we can still read it and switch the
controls. If you'd like to MOUNT the meter on your panel, buy two
right-angle UHF 90 degree adapters so we can mount the meter on the
front of the panel and the L-shaped connectors will go back through
the panel to connect the cables to. That would let you see power
output every time you keyed the VHF so you'd be SURE it was
transmitting, instead of calling out for a radio check so often. I
leave them in SWR to watch the antenna, here.

Hook the antenna to the antenna jack and the jumper between the Radio
jack and the radio. Turn on the radio and tune it to a commercial
channel not monitored by the DEA or USCG around 40-something. Put the
meter's little switch in the REFERENCE or SET position and turn the
set control all the way to the left, to keep from pegging the meter.
Test at FULL POWER so you can see if something up there is arcing at
FULL POWER (the meter jumps up in SWR if it is).

Key the transmitter and don't talk into the mic. Turn up the SET level
"volume" control until the meter reads FULL SCALE, all the way to the
SET mark. This sets the reference level of the meter to the power
coming out of the radio "under these conditions". Once set to full
scale, flip the switch to SWR and pray it drops all the way to 1 on
the SWR scale (no reflected power) indicating I was a liar and there
IS a perfect antenna system.....Read the pseudo-accurate meter SWR
scale. 1 is the left edge (1:1 standing waves - there aren't any
standing waves because the antenna is perfect). The next mark up is
probably 1.5 with hashmarkes for 1.4, 1.3, 1.2, 1.1, which is silly.
Then it's 2:1 then the middle of the meter is 3:1 SWR and there's no
marks higher because 3:1 is BAD, BAD, BAD....way too high. Unkey the
mic before the cops start looking for you.

What does this mean??

Here's the relative power levels of the major points.

1.0 SWR....no reflected power....all 25W is going out on the air
1.5 SWR.....4% reflected power....1 watt is reflected back, 24W goes
out and noone notices anything because you couldn't measure 4% out of
the lab.
2.0 SWR......10% reflected power...2.5W is reflected back and 22.5 W
goes out on the air and STILL noone notices anything unless they are
magicians.
3.0 SWR......25% reflected power....6.25W is reflected back and 18.75W
goes out on the air. Someone comparing this antenna with your perfect
antenna just notices a little movement in his S-meter on the other end
if you're weak. 3.0 and above is considered "bad SWR" and something
needs to be fixed.



CB myths........
1.01 SWR is good. 1.1 SWR is a disaster. What nonsense. Where do
they get this from? ANTENNA MANUFACTURERS selling new antennas,
that's where. They made millions from this myth. Wanna see a real
broadcast TV station's huge UHF antenna SWR LIVE on the net? Look at:
http://www.wzpxtv.com/wzpxtransmitter.htm
This a real readout of a powerful +megawatt TV transmitter from WZPX
on Channel 44 (with a nice new digital TV transmitter, too!) The
software company puts it on the net. SWR tonight on the
beast-on-the-mountain is 1.3:1 but I've seen it read 1.8:1 which is
really high at these power levels. On your boat, it's not. You don't
have thousands of watts coming back down the pipes at you!

Ok, now always turn the SET control back to the left before unhooking
the meter or changing channels. Do it now.....

Ok, make the same measurements on a few channels (not 16, 22A please)
across the marine band. Record your SWR results and make a crude
chart of them plotting SWR measured against channel (frequency) number
like I did above.

Is the lowest SWR near the middle of the channel numbers? No? Does
the curve at least have a low point (dip) inside the marine band?
Yes, but the dip is around Channel 3 and SWR is much higher at Channel
72 (why they could hear you on 16 but not 72 way off). The antenna is
tuned too LOW. If it's tunable, we need to shorten the element to
raise the resonant frequency. If 1 is high SWR and 72 is low, we need
to lengthen the antenna element. Ideal is a curve with its low point
somewhere in the middle of the band with less than 2:1 SWR on any
channel. The curve shows you where the antenna tuning is and how
broadbanded (how many channels will it radiate well).

If you measure this curve up at the antenna before all that cable
attenuates the SWR reading, it will simply be much more pronounced
because the cable attenuates power up as well as it does power down
the mast....making our reading weaker by a bit. AS you can see,
tuning an antenna ISN'T rocket science. If the channels you use are
all less than 2:1, it's fine. If they're less than 1.5:1, it's great.
If they're all really low....SOMETHING IS WRONG WITH THE ANTENNA, THE
CABLE OR THE MEASUREMENT, because every antenna has a curve.

Ok, we'll now haul a victim....er, ah, volunteer....up the mast to
trim the antenna the way it shows in the instructions......

You all should be able to measure SWR just fine with the little
meters, now, and have a vague idea of what it means.

Please leave the classroom quietly so's not to wake the four students
in the back row we lost. (Class quietly leaves, instructor slips out
and puts lights out with them still asleep. One once slept right
through lunch....(c



Larry W4CSC

"Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!"

One thing to consider and weigh in is the actual difference to the
receiver you're talking to...on-the-air...where it matters. Look at
any receiver or transceiver with a pseudo-calibrated S-meter. Notice
the DB scale above S-9. See how the marks are 10 dB apart? This is
also true down the scale.

So, before you all go hauling 7/8" hardline up the mast and boring
huge holes in the fiberglass to route it, the difference on-the-air,
where it counts is that instead of your signal being S-9 on somebody's
meter with 7/8" hardline and $200 connectors, you're RG-58 signal will
only be S-8.5 and noone will notice any difference....(c;

More CB myths. Most boats only have a 25-50' coax run. What I DO
recommend is a good Belden foil shielded cable, which will require
proper crimp connectors to make it work, not PL-259's from WalMart.
The 100% foil shield will keep locally generated noise OUT of the
cable on receive on its way from the antenna to your sensitive
receiver. You won't have to listen to the cheap straight plugs marine
engine manufacturers love to put in outboard and inboard motors,
instead of the resistor plugs they should be using. The foil coax
will also get a little more signal to the antenna on transmit, but
"big deal"....(c;

On Thu, 13 Nov 2003 09:33:27 -0500, Vito wrote:

Marcus AAkesson wrote:

On Wed, 12 Nov 2003 15:41:08 -0500, "Jim Woodward" jameslwoodward at
attbi dot com wrote:

4) What do you like other than the cheap white crap for antenna cable? I
used Belden 9913 (solid center conductor) on Swee****er. Is that still a
good choice?

RG214 or similar which is silver plated Cu in both conductor and
shield. Raw copper will in time oxidize and deteriorate in the salty
environment. I have seen some really ugly cables after only 5-6 years.


Check out http://www.therfc.com/attenrat.htm

Common RG-58A (the white crap) looses 7.4dB/100 ft at 200MHz. That's
over half your signal used to heat the coax! RG-8X (mini-RG8 - the other
white crap) is almost as bad at 5.4 dB/100'. Belden 9913 is excellent at
only 1.8dB/100. RG-214 has 3.3dB loss/100' but as Marcus suggests may
have better corrosion resistance. Of course if money, size and weight
are unimportant there's LDF5 (c:


Larry W4CSC

"Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!"

On Fri, 14 Nov 2003 11:47:11 -0000, "Brian Runyard"
wrote:

Larry

That's the best description I've seen, brilliant.
Regards,
Brian

Oh, p'shaw.....T'weren't nuthin....(c;....(blush)

I used to teach electronics 8 hours a day for 10 years.... After
you've gone over a subject 20 times, you get so you know it fairly
well! If you want to learn anything about any subject, get a job
teaching it to a bunch of teenagers trying to nail you to the
blackboard with real smart questions and you'll learn it QUICK!

"......but you said last week, and I quote....." You can hear that
nail gun compressor warmin' up in the back of the classroom...(c;

I'd much rather have the nail gun guys keeping me hopping than those
ones sleeping in the back of the side rows. We used to all sneak out
really quiet on them, shutting off the lights as quietly as
possible....leaving them sleeping in an empty, dark classroom with no
windows and no idea what time it is. Very effective in keeping them
awake..hee hee.

Thanks for your comment. Tomorrow, someone can come explain how the
hand-pumped, marine toilet functions and what it means when it refuses
to flush and makes that gurgling sound, instead. We'd ALL like to get
a little instruction on that piece of engineering!



Larry W4CSC

"Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!"

All true, in most cases. Maybe even here. My thinking, however, was that
Swee****er's tall stick (82 feet) did two things -- it made the lead
longer, so lossiness was more important -- and it put the antenna higher, so
we actually might be at the point where line of sight was less important
than signal strength, both going and coming.

We regularly talked to boats that were thirty to fifty miles away. Maybe
this is routine -- I don't know -- but I'd like to think that attention to
detail and the 9913 helped.


--
Jim Woodward
www.mvFintry.com


..

"Larry W4CSC" wrote in message
...
One thing to consider and weigh in is the actual difference to the
receiver you're talking to...on-the-air...where it matters. Look at
any receiver or transceiver with a pseudo-calibrated S-meter. Notice
the DB scale above S-9. See how the marks are 10 dB apart? This is
also true down the scale.

So, before you all go hauling 7/8" hardline up the mast and boring
huge holes in the fiberglass to route it, the difference on-the-air,
where it counts is that instead of your signal being S-9 on somebody's
meter with 7/8" hardline and $200 connectors, you're RG-58 signal will
only be S-8.5 and noone will notice any difference....(c;

More CB myths. Most boats only have a 25-50' coax run. What I DO
recommend is a good Belden foil shielded cable, which will require
proper crimp connectors to make it work, not PL-259's from WalMart.
The 100% foil shield will keep locally generated noise OUT of the
cable on receive on its way from the antenna to your sensitive
receiver. You won't have to listen to the cheap straight plugs marine
engine manufacturers love to put in outboard and inboard motors,
instead of the resistor plugs they should be using. The foil coax
will also get a little more signal to the antenna on transmit, but
"big deal"....(c;

On Thu, 13 Nov 2003 09:33:27 -0500, Vito wrote:

Marcus AAkesson wrote:

On Wed, 12 Nov 2003 15:41:08 -0500, "Jim Woodward" jameslwoodward at
attbi dot com wrote:

4) What do you like other than the cheap white crap for antenna cable?
I
used Belden 9913 (solid center conductor) on Swee****er. Is that
still a
good choice?

RG214 or similar which is silver plated Cu in both conductor and
shield. Raw copper will in time oxidize and deteriorate in the salty
environment. I have seen some really ugly cables after only 5-6 years.


Check out http://www.therfc.com/attenrat.htm

Common RG-58A (the white crap) looses 7.4dB/100 ft at 200MHz. That's
over half your signal used to heat the coax! RG-8X (mini-RG8 - the other
white crap) is almost as bad at 5.4 dB/100'. Belden 9913 is excellent at
only 1.8dB/100. RG-214 has 3.3dB loss/100' but as Marcus suggests may
have better corrosion resistance. Of course if money, size and weight
are unimportant there's LDF5 (c:


Larry W4CSC

"Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!"

"Larry W4CSC" wrote in message
...

SNIP

Thanks for your comment. Tomorrow, someone can come explain how the
hand-pumped, marine toilet functions and what it means when it refuses
to flush and makes that gurgling sound, instead. We'd ALL like to get
a little instruction on that piece of engineering!



Aw, sheeeet....


--
Jim Woodward
www.mvFintry.com


..

Any loss in cable is FAR amplified by ALTITUDE on VHF. It's why WCSC
has a 2000' tower. From 2000', a rubber duck antenna on a 1 watt
walkie talkie has a range of over 100 miles. Line of sight is what's
important. The only reason you need the power is to overcome noise
and the damned marinas docking boats from a 70' tower with a 9 dB
antenna running 25 watts to get to the end of the dock. Why the FCC
doesn't restrict marinas to 1W and 10' AGL has always been a mystery
to me. They're NOT part of any rescue party, manned by teenage girls.



On Fri, 14 Nov 2003 10:27:00 -0500, "Jim Woodward" jameslwoodward at
attbi dot com wrote:

All true, in most cases. Maybe even here. My thinking, however, was that
Swee****er's tall stick (82 feet) did two things -- it made the lead
longer, so lossiness was more important -- and it put the antenna higher, so
we actually might be at the point where line of sight was less important
than signal strength, both going and coming.

We regularly talked to boats that were thirty to fifty miles away. Maybe
this is routine -- I don't know -- but I'd like to think that attention to
detail and the 9913 helped.


--
Jim Woodward
www.mvFintry.com


.

"Larry W4CSC" wrote in message
...
One thing to consider and weigh in is the actual difference to the
receiver you're talking to...on-the-air...where it matters. Look at
any receiver or transceiver with a pseudo-calibrated S-meter. Notice
the DB scale above S-9. See how the marks are 10 dB apart? This is
also true down the scale.

So, before you all go hauling 7/8" hardline up the mast and boring
huge holes in the fiberglass to route it, the difference on-the-air,
where it counts is that instead of your signal being S-9 on somebody's
meter with 7/8" hardline and $200 connectors, you're RG-58 signal will
only be S-8.5 and noone will notice any difference....(c;

More CB myths. Most boats only have a 25-50' coax run. What I DO
recommend is a good Belden foil shielded cable, which will require
proper crimp connectors to make it work, not PL-259's from WalMart.
The 100% foil shield will keep locally generated noise OUT of the
cable on receive on its way from the antenna to your sensitive
receiver. You won't have to listen to the cheap straight plugs marine
engine manufacturers love to put in outboard and inboard motors,
instead of the resistor plugs they should be using. The foil coax
will also get a little more signal to the antenna on transmit, but
"big deal"....(c;

On Thu, 13 Nov 2003 09:33:27 -0500, Vito wrote:

Marcus AAkesson wrote:

On Wed, 12 Nov 2003 15:41:08 -0500, "Jim Woodward" jameslwoodward at
attbi dot com wrote:

4) What do you like other than the cheap white crap for antenna cable?
I
used Belden 9913 (solid center conductor) on Swee****er. Is that
still a
good choice?

RG214 or similar which is silver plated Cu in both conductor and
shield. Raw copper will in time oxidize and deteriorate in the salty
environment. I have seen some really ugly cables after only 5-6 years.


Check out http://www.therfc.com/attenrat.htm

Common RG-58A (the white crap) looses 7.4dB/100 ft at 200MHz. That's
over half your signal used to heat the coax! RG-8X (mini-RG8 - the other
white crap) is almost as bad at 5.4 dB/100'. Belden 9913 is excellent at
only 1.8dB/100. RG-214 has 3.3dB loss/100' but as Marcus suggests may
have better corrosion resistance. Of course if money, size and weight
are unimportant there's LDF5 (c:


Larry W4CSC

"Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!"





Larry W4CSC

"Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!"