Transcript Washington County ARES

https://www.youtube.com/watch?v=SbHWhvNmbL8
Washington County ARES
February 2015
Visitors
Please leave an email address on the sign up sheet
Upgrades & Certificates
Stations – Served Agencies
New computers for EOCs –
_---still waiting…
New Templates for Winlink –
RMS Express classes Lisa
Clark & John Core
Oregon ARES web site
oregonaresraces.org – register
and log in
ARES HF Net 3.964mhz – 1st & 3rd
Tuesdays have a message to give
Register with “mail chimp”
Who’s Who
OEM ARU : Oregon Emergency Management Amateur
Radio Unit
OEM : W7OEM
SEC : K7VV Vince Vanderhyde
DEC : District Emergency Coordinator
DEC : KD7WZI James Bryant
EC : KE7WKM Emergency Coordinator
County EOC : WC7EOC
WashcoARES.Org
Coaxial Cable
and
Connectors
10
Feedlines - overview
Connects the rig to the antenna
Most important characteristics are usually:
loss (varies with frequency)
characteristic impedance
power handling (varies with frequency)
balanced / unbalanced
physical characteristics
price
There are many types that can be used: selection is a
based on a series of trade-offs among these
characteristics.
11
Common Feedline Types
Coaxial cable:
RG-213 / RG-8*
0.4” diameter 50 ohms
RG-8X* / RG-8 MINI* 0.24” diameter 50 ohms
RG-58
0.2” diameter 50 ohms
RG-174
0.1” diameter 50 ohms
RG-6 (TV coax)
0.24” diameter 75 ohms
and many, many more…
* not a MIL STD cable designator
12
Dale’s general guidelines
Up to 1dB loss - don’t worry about it.
2dB loss - not optimum, but probably usable
3dB loss - find a better alternative if you can
Note: feedline loss is much more critical for VHF weak signal work,
or trying to be heard through a pile-up.
On VHF/UHF no feedline is too long if it runs vertically.
The loss due to length is more than overcome by the increase in
signal strength due to height.
13
Coax Loss (dB / 100’) vs. frequency and coax
type.
Coax recommendations
RG-58
Good for lower HF bands, marginal at 100’ on 15m and 10m
Light and flexible for portable antennas
Up to ~25’ on 2m
RG-8X / RG-8 MINI
Good for most HF use at reasonable SWR
Up to ~50’ on 2m
RG-213 (and relatives)
Best for most uses where weight isn’t important
Low loss types such as LMR-400 have slightly lower losses.
RG-6 TV cable (75 ohms)
Lower loss than RG-8X
Sometimes available surplus at very good prices
Aluminum shield - use crimp-on connectors
75 ohm impedance needn’t be a major problem
RG-174
Very small cable with higher losses - keep it short
Useful for backpacking where weight is critical
16
Coax Recommendations
RG-58:
Solid polyethylene inner insulation
Relatively cheap and commonly available
OK up to 200’ on 40m, 80m and 160m.
Marginal at 100’ on 15m and 10m
Up to about 25’ on 2m
Often used for mag mount leads because it can be
slammed in a car door.
17
Coax Recommendations (continued)
RG-8X / RG-8 MINI
No standard specification
Foam inner insulation
can be damaged by crushing or sharp bends
Smaller and more flexible than RG-213
Lower loss than RG-58
Good for most HF applications
Good up to 50’ on 2m
18
Coax Recommendations (continued)
RG-213 / RG-8 types
Suitable for most uses where weight isn’t important
Low loss types such as LMR-400 have slightly lower losses.
RG-6 TV cable (75 ohms)
Aluminum shield - use crimp-on connectors
75 ohm impedance needn’t be a major problem
RG-174
Very small cable with higher losses
Useful for backpacking where weight is critical
Small size can fit through small holes
19
Coax calculation tool: TLDetails
Coax calculation program from AC6LA
Free download for Windows machines
Calculates losses and impedance transformation based
on coax type, frequency and cable length.
http://www.ac6la.com/tldetails1.html
20
TLDetail
s
Losses and SWR
Feedline losses increase with SWR. (Well, mostly…)
This tends to be come more significant when the SWR is
over about 5 : 1 or so.
Just because you can match it with a tuner doesn’t
mean it is very efficient.
With high losses, the SWR at the rig will be less than it is
at the antenna.
The higher the cable loss to start with, the greater the
increase in loss due to SWR.
22
Increase in loss due to SWR
Coax cable tips
KEEP WATER OUT OF YOUR CABLE
reduces contact between wires in shield
increases losses, which improves SWR
Seal connectors, splices, holes
Prevent physical damage, especially with foam insulation
crushes easily (step on it, bend too tight, tie wraps)
foam acts like a sponge if water gets in
Run in conduit if underground, or to protect from animals
27
Connector types
PL-259 / SO-238 “UHF”
most common type on base and mobile rigs
usable up to 450 MHz
designed for RG-213 size cable, use sleeve for smaller types
Type N
Higher quality connector
Supposed to be waterproof
Better at UHF
BNC
quick connect/disconnect (push and twist 1/4 turn)
used on many older HTs
SMA
used to save space on small HTs
Not as strong
Solder vs. crimp-on connectors
28
Connector tips
USE THE RIGHT TYPE OF CONNECTOR FOR YOUR COAX
You can use the same PL-259 for RG-8X and RG-59, but you can’t
use the same BNC connectors.
Crimp connectors must fit just right, and be crimped with the proper
tool
End of connector shell is the point of maximum flexing / stress
Provide strain relief so connectors aren’t under tension
Losses in properly assembled connectors and adaptors are quite low.
29
Common causes of problems
Water in the coax
broken braid (or center) from flexing at connector
braid improperly soldered on PL-259
worn or recessed center pin (especially BNC)
female socket splayed out from PL-259 with extra solder
stray strand of shield shorting out to center conductor
connector insulation damaged by heat of soldering
31
DSTAR Net
N7QQU B @ Synopsis
Sundays at 6PM Voice 440.550
8PM Digital 440.550
http://www.dstargateway.org/
https://n7qqu.dstargateway.org/
DSTAR Class
Ronler Fire Station
st
Feb 21
9:00AM to 12PM
 Cue Chris KU7PDX
Winlink Class –
I Want It All!!
 Location Ronler Fire Station
March 14th
9AM to 12PM
 TNC’s
 Radios
 Packet
 Pactor
 Cables
 Dummy Loads
 Get your hands on everything
Task List 1
 John Core KX7YT
 Sam Corbin KF7BUC
 John Bucsek KE7WNB
 Kent Powloski N7KPN
 Pat Flanagan KE7NVB
 Richard Stack K7TKK
 Frank Wenzel AE7IS
 Bob Yolton W7ZXX
State and Federal CSZ Plans
Cascade
Rising
Quake Ex I
April 25th
 A Joint FEMA-OEM Exercise, June 2016
 FEMA Region 10 has recently released the Cascadia Rising Exercise
Scenario Document which has just been posted at:
 http://www.oregonaresraces.org/?page_id=559
 This is a large file about 7 Mb in size with many maps of expected damage
from a CSZ quake based on the most recent research. Our Spring and Fall
SETS this year will be based on this document. You will find it very interesting
reading.
 John Core, KX7YT
 ASEC SET Coordinator
Run with Paula
5/3/15
Kiezer Volcanoes
Morning ham radio
440.350mhz
Tone 127.3
+5Mhz Offset
Anything Else