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Last Edited:
12-Sep-2004

TYPE (Click to see Full-size) CONFIGURATION YEARS (approx) COST NEW ($) COMMENTS, 
(tech notes)
TUBES
310(A) Scott_310.jpg (13941 bytes) FM-Mono
Broadcast Monitor
 Tuner
1954-1957 $170
1st Scott FM Tuner;

Used Unusual (bottom-edge) Slide Rule Tuning
, with illuminated indicator and coarse tuning slider.

tubes mounted on inverted sub-chassis;

Front panel controls:
level, squelch ("Dynaural Inter-station Noise Suppressor), and vernier tuning knobs.

All Scott 310-series tuners feature a unique 5-tube/4-can IF/limiter section.

The 310A was the only 310 model to use a 6X5GT rectifier and dual 12AU7 final DINS/amp section.

Used narrow "D" Case.
10 Tubes:

Front End:
(1) 6BK7A or 6BS8/6BQ7A
(1) 6U8;

IF:
(4) 6AU6
(1) 6BN6

AF AMP:
(1) 12AU7

Squelch (DINS):
(1) 12AU7

Rectifier:
(1) 6X5GT

310-B Scott_310B.jpg (22158 bytes) FM-Mono
Broadcast Monitor
Tuner
1957-1958 $155
Simplified repackaging of the "inverted" 310A; using design concepts introduced on the 311-A

 First 310 to use famous Scott round tuning dial  with planetary, co-axial (vernier) tuning knobs and simplified, non-inverted chassis.

The 310-B introduced both tape and multiplex output jacks for use with the 335/LM-35 outboard adaptor.

Introduced the 12AX7/12AU7 DINS/final output amp

"Silver-Plated" (Modular) Front-End introduced,

Used narrow "D" case/chassis.

10 Tubes:

Front End:

(1) 6BS8/6BQ7A
(1) 6U8;

IF:
(4) 6AU6
(1) 6BN6

AF AMP:
(1) 12AX7

Squelch (DINS):
(1) 12AU7

Rectifier:
(1) 6X4

310-C Scott_310C.jpg (11114 bytes) FM-Mono
Broadcast Monitor
Tuner
1958-1960 $170 Essentially identical to 310-B (above)

with minor cosmetic updates

"Conical Peg-style"  replaces co-axial (vernier) tuning knob.

Used narrow "D" case/chassis

10 Tubes:

Front End:

(1) 6BS8/6BQ7A
(1) 6U8;

IF:
(4) 6AU6
(1) 6BN6

AF AMP:
(1) 12AX7

Squelch:
(1) 12AU7

Rectifier:
(1) 6X4

310-CR 310_C_R.jpg (60542 bytes) FM-Mono
Broadcast Monitor Tuner

 Rack Mount
1959-1961 $220 Same as 310-C (above) but the "CR" was sold by H.H. Scott, Instrument Division, for professional applications.

Featured RETMA, 5.25-inch x 19-inch rack-mount faceplate.

For $35.00,  an optional 600/150-ohm balanced output transformer was available.

10 tubes:

Front End:

(1) 6BS8/6BQ7A
(1) 6U8;

IF:
(4) 6AU6
(1) 6BN6

AF AMP:
(1) 12AX7

Squelch (DINS):
(1) 12AU7

Rectifier:
(1) 6X4

310-D Scott_310D.jpg (11740 bytes) FM-Mono
Broadcast Monitor
Tuner
1960-1962 $190
Last "Mono" 310 variant

Wide Chassis Introduced, "C" Case (anticipating space for multiplex decoder?)

Used 12AU7 AF amp, instead of 12AX7

Improved squelch ("Dynaural Interstation Noise Supressor or DINS")

Introduced high-speed muting (relay-driven) circuits,  & diversity reception opt., both later seen on the 4310

 (Note: Front-panel layout easily confused with the early 350 FM-MPX stereo types.)


10 Tubes:

Front End:

(1) 6BS8/6BQ7A
(1) 6U8;

IF:
(4) 6AU6
(1) 6BN6

AF AMP:
(1) 12AU7

Squelch (DINS) Relay Driver:

(1) 7247/12DW7

Rectifier:
(1) 6X4

310E Scott_310E_Front.jpg (10113 bytes)



Scott_310E_Rear.jpg (16905 bytes)
FM-MPX Stereo
Broadcast Monitor
Tuner
1963-1964 $300
Final evolution of the 310 series (and only to feature MPX). Considered by many to be Scott's finest performing tuner design.

Built on std. "C" Case, wide chassis,

(unlike the bigger 4310, which used the taller "G" chassis.)

Included dual relays for Squelch (DINS) circuit and Auto-Sensor Stereo MPX detection both with new green jewel indicators;

Featured unique Selector switch which permitted user to exclude all mono broadcasts;

Featured unique front-panel Stereo Threshold Control permitting user to set minimum acceptable multiplex signal levels. 

Used 6V4 rectifier

Dropped diversity option of 310-D,

added Extruded Front Panel Styling (Capped ("Pegless") Tuning Knob), Dark Brown Tuning Dial background.

15 tubes:


Front End:

(1) 6BS8/6BQ7A
(1) 6U8;

IF:
(4) 6AU6
(1) 6BN6

MPX:
(1) 6U8
(2) 12AU7
(1) 12AX7

AF AMP:
(1) 12AT7

RELAY DRIVERS:

(2) 7247/12DW7

Rectifier:
(1) 6V4

311(A) Scott_311.jpg (12372 bytes) FM-Mono
Tuner
1955-1956 $100
Significant Scott tuner design; but often over-looked.

Lower-cost version of 310 (two-thirds the cost of a 310);

First use of famous Scott round tuning dial, using co-axial (vernier/reduction) tuning knobs.

The 311 also introduced the 3-tube IF/Limiter section which was used on ALL Scott tube tuner designs (except the 310-series) and the final "Compactron" 370/LT-111 design.

Economies were achieved by using the 3-tube /3-can IF section (eliminating the 310's 6BN6 gated-beam limiter) and eliminating the 310's "Squelch" and replacing the 310's dual 12AU7 audio output drivers with a single 12AX7.

Introduced the MPX output jack for use with the 335/LM-35 multiplex adaptors.


Red plastic dial pointers, on early models
Used narrow "D" case/chassis.
7 Tubes:

Front End:

(1) 6BS8/6BQ7A
(1) 6U8;

IF:
(3) 6AU6

AF AMP:
(1) 12AX7

Rectifier:
(1) 6X4

311-B Scott_311B.jpg (17526 bytes) FM-Mono
Tuner
1956-1958 $120
See 311(A) details above,

Early versions had red plastic dial pointers (see above),

"Silver-Plated" (Modular) Front-End introduced,

used narrow "D" case/ chassis


7 tubes:

Front End:

(1) 6BS8/6BQ7A
(1) 6U8;

IF:
(3) 6AU6

AF AMP:
(1) 12AX7

Rectifier:
(1) 6X4

311-C Scott_311C.JPG (15160 bytes) FM-Mono
Tuner
1959-1960 $120 Essentially identical to 311-B (above)

minor cosmetic changes


 used narrow "D" case/ chassis


7 tubes:

Front End:

(1) 6BS8/6BQ7A
(1) 6U8;

IF:
(3) 6AU6

AF AMP:
(1) 12AX7

Rectifier:
(1) 6X4

311-D FM-Mono
Tuner
1960-1961 $120 See 311(A)/B/C
details above,

Final variant of 311 series,

"Conical Peg-style"  replaces co-axial (vernier) tuning knob.

used narrow "D" case/chassis

7 tubes:

Front End:

(1) 6BS8/6BQ7A
(1) 6U8;

IF:
(3) 6AU6

AF AMP:
(1) 12AX7

Rectifier:
(1) 6X4

314 Scott_314.jpg (16768 bytes) FM-Mono
Tuner
1961-1963 $115 Low cost, Wide-Chassis refinement of 311 design

Used 6FG6/EM84 tuning-eye tube instead of meter,

Eliminated 12AX7 audio amp and 6AU6 limiter tubes,
replaced with single 6AU8 tube.

 Wide "C" Case/chassis,

also see Kit version, LT-10

7 tubes:

Front End:

(1) 6BS8/6BQ7A
(1) 6U8;

IF:
(2) 6AU6
(1) 6U8

AF AMP:
(none) shares 6U8

Rectifier:
(1) 6X4

Tuning Eye:
6FG6/EM84

335 Scott_335.jpg (20953 bytes) MPX Stereo
 Adaptor
1961-1963 $110
Outboard (self-powered) MPX stereo adapter for adding stereo decoding to Wide-band FM-mono Tuners.

The basic 335 design was also shared in the 333, 350 and LT-110 MPX tuners.

The multiplex decoder used a 6BL8 as a composite buffer and 19 kHz amplifier.

 A 12AU7 was used for the 38 kHz oscillator. Another 12AU7 was used as an audio stereo matrix circuit.

 A 12AT7 was used as the audio output amplifier and a 6X4 rectifier provided power.

The 335 used narrow "H" case/chassis

also later offered
as the
LM-35 Kit version

5 tubes:

MPX:

(1) 6BL8
(2) 12AU7

AF AMP:
(1) 12AT7

Rectifier:

(1) 6X4
350(A) Scott_350.jpg (15137 bytes) FM-MPX-Stereo
Tuner
1961-1962 $195
The Type 350 introduced true MPX-Stereo. The 335 MPX decoder design was married to the 311/314 tuner on a wide "C" chassis.

Front panel level control was provided.

An optional
Type C-55
 "Stereo Guide" indicator tube (6AV6) was located at
the 6 o'clock position of the tuning dial,

The original 350's had no Tape Output jack on the front panel.

350(A) front panel layout very similar to 310-D.

 used wide "C" Case/chassis


10 tubes:

Front End:

(1) 6BS8/6BQ7A
(1) 6U8;

IF:
(2) 6AU6
(1) 6BN6

MPX:
(1) 6BL8
(2) 12AU7

C-55
"Stereo Guide":

(1) 6AV6

AF AMP:
(1) 12AT7

Rectifier:
(1) 6X4
350B Scott_350B.jpg (12188 bytes) FM-MPX-Stereo
Tuner
1962-1963 $200
See "Editor's Picks"

The 350B
added front panel Tape Output jack, 

The "Sonic Monitor" switch replaced level control and "Stereo Guide," was absent.

Selenium rectifier for B+,

also see Kit version, LT-110,

used wide "C" Case/chassis


9 tubes:

Front End:
(1) 6BS8/6BQ7A
(1) 6U8;

IF:
(3) 6AU6

MPX:
(1) 6BL8
(2) 12AU7

AF AMP:
(1) 12AT7

(1) Selenium Bridge

350C Scott_350C_Front.jpg (18222 bytes) FM-MPX-Stereo
Tuner
1963-1964 $220 The 350C added the new "Extruded" Front Panel Styling

(Capped ("Pegless") Tuning Knobx),

Dark Brown Tuning Dial background,

also see Kit version, LT-110B,

 used wide "C" Case/chassis

9 tubes:

Front End:

(1) 6BS8/6BQ7A
(1) 6U8;

IF:
(1) 6EJ7/EF-184
(1) 6AU6
(1) 6U8

MPX:
(1) 6BL8
(2) 12AU7

AF AMP:
(1) 12AT7


(1) Selenium Bridge

350D Scott_350D.JPG (10216 bytes) FM-MPX-Stereo
Tuner
1964-1967 $225 Final evolution of the 350-series.

Only Scott FM Tuner to use sidewinder mounted tuning gang.

The 350D added Auto-Sensor Mono/MPX switching
using the revised Z-MX-8 section, derived from 340B receiver

The 350D also featured a selectable
Multipath or
Signal Strength
"Magic-eye"  6HU6/EM87
indicator

Slide Rule Tuning Dial
(as introduced on 340B and shared with later solid-state models)

Extruded Front Panel styling


 used wide "C" Case/chassis


9 tubes:

Front End:

6BS8 - V201
6U8 - V202

3-tube, IF:
6EJ7 - V1
6HS6 - V2
6U8 - V3

3-tube MPX section, Z-MX-8:
12AT7 - V501
6KE8 - V502
12AX7 - V503

Tuning-Multipath Indicator:
6HU6/EM87 - V4

(1) Selenium Bridge

370 Scott_370.JPG (12495 bytes) FM-MPX-Stereo
Tuner
1962-1963 $150
The 370 was Scott's low-cost Stereo-MPX tube tuner design, marketed along side the more expensive 350B/C, 310E, and 4310

The 370 featured low-cost, Compactron Tubes (6M11 & 6AG11), also use in the 345 receiver.

370's were unique in their use of vacuum tube diodes in the multiplex decoder switching matrix.

A 6HU6/EM87 tuning-eye tube was used for the tuning meter

Visually the front panel is very similar to FM-mono 314, the 370 uses a "tighter" (one-piece) tuning-eye aperture

also see
Kit version, LT-111
,

used wide "C" Case/chassis

7 tubes:

Front End:

(1) 6M11

IF:
(2) 6AU6
(1) 6HS6

MPX:
(1) 6HU6/EM87
(1/2) 6AG11

AF AMP:
(1/2) 6AG11


(1) 6X4

370B FM-MPX-Stereo
Tuner
1963-1965 $150 As 370(A) above, with identical circuitry;

but with updated Extruded Front Panel Styling
 
7 tubes:

Front End:

(1) 6M11

IF:
(2) 6AU6
(1) 6HS6

MPX:
(1) 6HU6/EM87
(1/2) 6AG11

AF AMP:
(1/2) 6AG11


(1) 6X4

4310  Broadcast Monitor Series
FM-MPX Stereo Tuner
1963-1965 $475.00
Flagship Scott Tube FM-MPX Tuner

Separate Left/Right VU Meters

Separate Left/Right and Master Level Controls

Diversity Reception Switch

Stereo Threshold and DINS (squelch), Relay-switched mono/stereo operation

used large format "G" case, as did 272, 296, 340, 355 types

22 lbs.

 


20 tubes:

(4) 6AU6
(2) 12AU7
(4) 7247/12DW7
(1) 6BS8
(2) 6JU8
(1) 6BL8
(2) 6T8
(1) 12BH7
(1) 6BN6
(1) 6AL5
(1) 6U8

(2) Selenium Rectifiers

 

For a detailed technical description see: John Byrns's History of H.H. Scott Tuners.

To view: Vintage H.H. Scott FM Tuner Kits.

 

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