| Author |
Message |
    
Jd1020
New member
Username: Jd1020
Post Number: 2
Registered: 10-2006
| | Posted on Tuesday, December 05, 2006 - 6:25 pm: | 
|
If I put up an Antron 99 antenna, friends tell me I need 50 ft. of coax cable. My question is: To locate the radio where I want to in the house, I need at least 75 ft and possibly 100 ft. Would this change the SWR setting or decrease the antenna reception and output? Can you screw 2 different lengths of coax cable together without any problems? |
Streaky
Member
Username: Streaky
Post Number: 70
Registered: 3-2006
| | Posted on Tuesday, December 05, 2006 - 10:31 pm: |
|
Jd1020
If you use high quality coax (eg. LMR 400)or equivalant then 100 foot runs are no problem.It will not change the swr and from what I have read on this forum if you use abarrel connector you can attach another peice ofcoax with hardly any loss at all
Streaky
CEF #805
CVC #98 |
Tech808
Moderator
Username: Tech808
Post Number: 12451
Registered: 8-2002
| | Posted on Tuesday, December 05, 2006 - 11:37 pm: |
|
Jd1020,
I would suggest RG-213 or the 
Altelicon CA-400 400 Series Cable which is far more reasonable in price than the LMR and has the EXACT same Specs.
CLICK on the BLUE LINK BELOW!
Altelicon CA-400
CA-400 Series Coax Cable
The CA-400 low loss cable is a high performance alternative to RG8/U, CommScope® WBC-400, Times Microwave Systems® LMR-400, Belden® 9914 / 9913 / 7810 and Andrew® CNT-400 coax cable.
Altelicon CA-400 is a UV resistant polyethylene lacketed high performance flexible Low Loss coaxial cable. This coaxial cable has become a "standard" of the outdoor wireless LAN and WLL industries. This lightweight cable has excellent low loss characteristics and a durable UV protected black polyethylene jacket. The Altelicon CA-400 features equal performance and mechanical characteristics to cables from CommScope®, Times Microwave Systems®, Belden and Andrew®.
Construction Specification (Layer - Material - Diameter)
Inner Conductor - Copper/Aluminum - 2.74mm / 0.108in
Dielectric - Physical Foam Polyethylene - 7.24mm / 0.285in
Outer Conductor - Bonded Aluminum Foil + Tinned Copper Braid - 8.13mm / 0.320in
Jacket - Black Polyethylene - 10.29mm / 0.405in
Electrical Characteristics
Capacitance : 77.1pF/m
Impedance : 50ohm
Velocity : 85%
Inner Conductor DC Resistance : 2.92(Ω/km)
Outer Conductor DC Resistance : 5.41(Ω/km)
Shielding Effectiveness : > 90dB
Cutoff Frequency : 16.2 GHz
Peak Power : 16KW
Mechanical and Environmental Characteristics
Min. Bend Radius : 51mm / 2.0in
Operating Temp. : -40°C to +80°C
Tensile Strength : 72.6kg / 160lb
Cable Weight : 0.099kg/m 0.068lb/ft
RoHS Compliant : Yes
Attenuation and Avg. Power (20°C)
(Frequency - Attenuation dB - Avg. Power)
30MHz - (2.2@100m / 0.7@100ft) - 3.30KW
50MHz - (2.9@100m / 0.9@100ft) - 2.60KW
150MHz - (5.0@100m / 1.5@100ft) - 1.50KW
220MHz - (6.10@100m / 1.86@100ft) - 1.20KW
450MHz - (8.9@100m / 2.7@100ft) - 0.83KW
900MHz - (12.8@100m / 3.9@100ft) - 0.58KW
1500MHz - (16.8@100m / 5.13@100ft) - 0.44KW
1800MHz - (18.6@100m / 5.67@100ft) - 0.40KW
2000MHz - (19.6@100m / 6.0@100ft) - 0.37KW
2500MHz - (22.2@100m / 6.8@100ft) - 0.33KW
5800MHz - (35.5@100m / 10.8@100ft) - 0.21KW
Hope this help's,
Lon
Tech808
CEF808
N9CEF
CVC#2 |
Wildrat
Senior Member
Username: Wildrat
Post Number: 1159
Registered: 12-2003
| | Posted on Wednesday, December 06, 2006 - 12:02 am: |
|
JD1020,
I use the RG-213 that Copper sells and my run is around 120'. My SWR are nearly flat with my Imax 2K, and with the box on they are around 1.3. Don't worry to much about your coax length, just make sure all your connectors are soldered good.Well it's just past midnight and I am falling asleep, if you have more qurstions just ask.
WR |
Wildrat
Senior Member
Username: Wildrat
Post Number: 1160
Registered: 12-2003
| | Posted on Wednesday, December 06, 2006 - 12:09 am: |
|
Missed your other question about connecting two cables. Yes you can, again make sure you have good connections and water tight. You may want to consider putting a PolyPhaser in the circuit.
WR |
Uillean
New member
Username: Uillean
Post Number: 3
Registered: 12-2006
| | Posted on Wednesday, December 06, 2006 - 8:17 am: |
|
JD,
Barrel connectors are not a problem, just make sure the PL259s are put together well (no solderless connectors!)and be sure to wrap the whole assembly with a good quality vinyl tape to keep water out. I have 2 barrels inline on the way to my quad (one at the 1/4 wave matching section and one 20 feet farther down--long story on that one) and in my case used this dielectric goop sold by Radioworks just because I happened to have some on hand (Copper may sell something similar), and wrapped the connectors with black water seal tape you can get at Home Depot.
It's been up over a year with no problems, VSWR is still below 1.2:1 over the 40 channels and doesn't rise above 1.5:1 anywhere I use it. Never has changed a bit during this time. |
Tech237
Moderator
Username: Tech237
Post Number: 648
Registered: 4-2004
| | Posted on Wednesday, December 06, 2006 - 12:49 pm: |
|
JD,
Take look at the article (under Subscriptions/Articles) about coax length as this may give you a better understanding of the effects coax length can have on your system.
The loss on a 100ft of GOOD quality coax, such as the one suggested by Tech808, is minimal at 27MHz BUT the length can affect the apparent SWR of your antenna system.
Now as to barrel joiners although they cause little loss - if all solder joins are high quality and the connections are clean, moisture and dust can creep in not matter what you do. In all most all professional and commercial installations joins are avoided, and in order to prevent yourself from having future trouble I strongly suggest running you coax as a single piece.
This advise (if you are wondering) is backed by over 30 years of professional experience, which includes designing and implementing statewide radio systems for several Australia Emergency organizations. |
Sonny
Intermediate Member
Username: Sonny
Post Number: 128
Registered: 5-2004
| | Posted on Wednesday, December 06, 2006 - 8:08 pm: |
|
JD get as close as you can to a full wave length like 108ft. 36ft being a full wave length  |
Jd1020
New member
Username: Jd1020
Post Number: 3
Registered: 10-2006
| | Posted on Wednesday, December 06, 2006 - 8:53 pm: |
|
Thanks to everyone for your replies and helpful information. I picked up my antenna and coax today from Coppers. Hopefully the weather will be where I can get it up this week-end. Thanks. Dale |
Uillean
New member
Username: Uillean
Post Number: 4
Registered: 12-2006
| | Posted on Wednesday, December 06, 2006 - 11:45 pm: |
|
Good Luck Jd.
(And a full wave length of coax at 27.2 MHz is either 31.8' or 23.8', depending on whether the dielectric is foam or poly. If that matters to you).
Uillean |
Tech808
Moderator
Username: Tech808
Post Number: 12463
Registered: 8-2002
| | Posted on Thursday, December 07, 2006 - 5:47 pm: |
|
COPPER ELECTRONICS
Coax Line Loss Calculator
CLICK BELOW!
Coax Line Loss Calculator
Lon
Tech808
CEF808
N9CEF
CVC#2 |
