Eico HFT 90 Owners Manual

Page 2

MOBIL H" 90 HIGH FIDELITY FM TUNIR

general description
GENERAL

Among the most advanced of the FM tuner designs both
electrically and mechanically, the EiCO HIFT90 FM Tuner
kit is equal to or surpasses wired tuners up to three times
the price. it is the first kit to include an entirely pre-
wired and pro-aligned " front end" (housed and completely
shielded in a solid aluminum-zinc casting). Tl1ls"front
end" not only provides extremelyhigh sensitivity and low
noise, but is also entirelystabieand guaranteed drift-free.
Through the use of the most advanced circuitry and temp-
erature _compensated components, the need for AFC is
completely eliminated and drift is less than 2 parts in i0,000
from cold start. This "front end" makes completely prac-
tical, even for a novice, the building of on FM tuner kit
equal to really good factory-wired units.

Furthermore, the kit is supplied with the IF and Ratio
Detector transformers pre-aligned in manufacture, Thus
every tuned circuit in the tuner is pre-alignedand a com-
pleted tuner kit will give satisfactory reception without
alignment providing that the indicated layout of compo-
nents and wiring is followed.

SPECIFICATIONS

Sagitiviy: i.5uv for 20db quieting; 2.5uv for 30db
quieting; full limiting from 25w.

lngu : 300 ohms balanced.
Frguencx Response: Uniform from 20 to 20, OOOcps ii db
iF Bandwidth: 260kc at 6db points.

Detector Charactgristic: Peak separation of 600 kc. Lin-
ear bandwidth of400 kc. Broadband ratio detector pre-

ceded by stabilized limiter stage.

Stability: Maximum drift of 20kc from cold start. Stable
after approximately one minute.

Radiation: Complete shielding of oscillator circuit and
tube in preassembled "front end" minimizes radiation.

The HFT'90 is the firstkit, also to include the DM'70 trav-
eling tuning eye which travels along the side-rule dial as
a luminous "exclamation point indicator, figfllfllflgfii :
thmgaactcentgrgfheach broadcast change] . Having a sen-
sitivity over six magazine. other kit tuners and
equaling the most expensivewired tuners, the HFT'90 pro-
vides excellent reception even in fringe areas. Other per-
formance features include fly-wheel tuning, automatic gain
control, stabilized low limiting threshold for excellent per-
formance from weaker signals, broad-band ratio detector
for improved capture ratio and easier tuning, ful l-wave
rectifier and heavy-filtering, and very low distortion plus
flat frequency response for superb audio quality.

The HFT'9O utilizes a low-silhouette construction, utiliz-
ing a horizontai chassis to permit properlayout and com-
ponent separation necessary for long component lite and
stability. The important construction aids include simpli-
fied dial cord arrangement pre-wired tuning eye assembly.
Extremelyflexible design permits easy consoleinstallation
with adaptabilityto panel thicknesses up to3/8inch. Op-
tional cabinet may also be used in console installation to
provide additional shielding.

Outgu : Two provided; cathode follower and multiplex.
Cathode follower permits use of up to 200 ft. of con-
necting cable. For lOuv input with 75kc deviation,
an audio output 1.0 volt is obtained.

Hum: 60db below i volt.

Controls: Tuning, Volume/Off.

Tubes; 1" ECC85/6AQB grounded grid r'f amplifier and
reflex converter; 2 6AU6 1F amplifiers; i" 6AU6 IF
amplifier/limiter; i6AL5dual diode detector; 1 DM70
tuning indicator; 1" 6C4 cathode follower output; 1-
6X4 full wave rectifier.

Powgr: iiO'iZ5vac, 60cps; 40 wattsdrain.

Size: HWD: 35/ ", 12", 81/"

Shipping Weight: i0 lbs.

COPYRIGHT© i958 ELECTRONIC INSTRUMENT COMPANY, Ins.