Coaxial cable is the most familiar form of RF transmission line
for most people these days. Up until 2009 when the U.S. switched
to digital television (DTV), there
were still a fairly large number of people who had the old 300 Ω
twin lead cable running from roof-top antennas to TV sets. Over-the-air
reception has petered off precipitously since then. Coaxial
cable is undoubtedly more convenient and forgiving regarding
routing since proximity to structures - particularly metallic
components - than twin lead. Good quality 300 Ω twin lead
cable (~30¢/foot today) used
to cost less than good quality 75 Ω RG59 cable
(~12¢/foot today), but just a
couple decades ago when twin lead dominated, the opposite was
true. What has not changed is the insertion loss of 300 Ω
twin lead cable is typically around 2 dB at VHF TV channel
frequencies (54-210 MHz),
and 450 Ω ladder line (twin lead
on steroids) is about 1/2 or less of that
Figures for 300 Ohm Twin Line"). Insertion loss on
RG-59 coaxial cable is around 4 dB/100' in the same band
(RG-6 is ~3 dB/100', and RG-11 is
~2 dB/100'). The lower you go in frequency, the
lower the loss in both cable types, but twin leads gets better
Federal Telephone and Radio Company Ad
North, East, South, West ...
Wherever there are TV customers ...
Federal has a lead-in for the finest VHD-UHF
Whatever the area or atmosphere ... city or fringe ... rain,
snow ice, heat, dust, salt spray, polluted air or radiation
... you'll find the answer in these quality-controlled cables
by Federal -
For Community TV it's Federal's "Big 5"
K-14 - 71-ohm shielded primary transmission line for community
distribution systems. Famous for lowest line loss, long cable
runs and fewer amplifiers required. Capacitance: 21.5 mmf/ft.
Attenuation DB 100/ft: .57-50 Mc; .90-100 Mc; 1.42-200 Mc; 2.3-400
RG-11/U - 7 5-ohm shielded low-loss coaxial. One of the best
small-diameter cables. Tops as a community TV secondary lead-in.
Seven strands #26 tinned copper. Capacitance: 20.5 mmf/ft. Attenuation
DB 100/ft: 1.5-50 Mc; 2.15-100 Mc; 3.2-200 Mc; 4.7-400 Mc.
RG-59/U - 73-ohm coaxial TV lead-in cable. Highly efficient
as a community system pole-to-house tap-off. Meets all needs
wherever a high-grade installation is a must. Capacitance: 21
mmf/ft. Attenuation DB 100/ft: 2.7-50 Mc; 4.0-100 Mc; 5.7-200
Mc; 8.5-400 Mc.
K-111 - 300-ohm shielded, balanced TV lead-in developed by
FTR. Minimizes noise, snow, ghosts due to transmission line
pick-ups. Ideal for many areas where good TV was impossible
before. Capacitance: 4.2 mmf/ft. Attenuation DB 100/ft: 3.4-100
Mc; 6.6-400 Mc.
TV-1184 - 300-ohm dumbbell-shaped TV lead-in. A standard
low-cost lead-in for areas without unusual conditions. Cinnamon-brown
color is highly resistant to ultra-violet. Two conductors: 7/#28.
Capacitance: 4 mmf/ft. Attenuation DB 100/ft: 1.28-100 Mc; 3.0-400
TV-1182 - 300-ohm deluxe type heavy-duty TV lead-in with
90 mil. web. Insulated with "silver" polyethylene, Federal development
that provides maximum weather protection and long life. Capacitance:
4 mmf/ft.Attenuation DB 100/ft: 1.22-100 Mc; 2.85-400 Mc.
Non-Radiating Lead-ins for Multiplex TV Systems
K-125 - 75-ohm coaxial TV lead-in cable. Double-shielded
and jacketed. Formerly listed as SP-75.
Use these 2 for Community TV radiation
K-126 - 73-ohm coaxial TV lead-in cable. Double-shielded
and jacketed. Formerly listed as SP-76.
K-125 alternates for·RG-11/U as secondary lead-in
K-126 alternates for RG-5S9/U as tap-off lead-in
... "Pipeline" of the Air!
300-Ohm All-Channel Twin-Lead that Laughs at Weather
For Fringe Areas
TV-1182 - Provides remarkably low line loss in fringe areas.
Outstanding for resistance to weather and sunlight. Silver-colored
insulation blends with any color scheme in home decoration.
K-200 (RG-86/U) - 200-ohm heavy-duty ultra low-loss lead-in.
Particularly adaptable to remote-area installations - especially
long runs and multi-stack antennas. Also used with rombics.
See your local Federal Distributor or write to Federal direct
TV-1185's "Silver" pigmentation lets you
Install it and Forget it!
Federal's TV-1185 is virtually a "pipeline" for better-than-ever
TV reception ... VHF or UHF. Insulated with the revolutionary
Federal-developed "silver" polyethylene, TV-1185 is amazingly
tough, flexible and efficient.
TV-1185 leads in Weatherometer tests ... fights heat, resists
moisture and other destructive deposits ... minimizes deterioration
due to sunlight.
TV-1185 keeps the energy field inside the weather-proof sheath
... providing exceptionally low loss ... more constant impedance
... a better TV picture regardless of area or length of lead.
It's easy to install and tight-seal against all atmospheric
There's no finer tubular lead-in of its type on the market
Capacitance: 4 mmf/ft. Attenuation DB 100/ft: 0.5-10 Mc;
0.95-50 Mc; 1.25-100 Mc; 1.7-200 Mc; 2.6-400 Mc; 3.0-500 Mc;
Product of America's leading producer of solid dielectric
Federal Telephone and Radio Company
100 Kingsland Road, Clifton, N.J.
In Canada: Federal Electric Manufacturing Company, Ltd.,
Montreal, P. Q.
Export Distributors: International Standard Electric Corp.,
67 Broad St., N. Y.
Posted June 16, 2015