MECHANICAL ASSEMBLY ADJUSTMENTS
These adjustments are listed in the order in which they would be performed on a machine which is completely out of adjustment. Changing one adjustment will often affect succeeding adjustments end units should be carefully checked for proper adjustment after repairs have been made. If caution is used in dismantling units for repair, it is possible to avoid a great deal of labor.

A: Motor mounting. To replace drive roller (A - 181) re novo four screws (8-115) from rubber mounting points, lift out motor without disconnecting lends from switch terminals. Remove screw (S - 216), immerse drive roller in Acetone solvent until adhesive bond softens. Remove drive roller from shaft.

B: Control knob should be set on transfer shaft with get screw against the flat and to detect lever (A - 109) setscrews should be tightened so that knob is vertical when the lever is in trough of detent slide (M - 107), 1.9, in " stop " setting.

C: Tighten setscrews of motor transfer lover (A - 110) when drive lover (A - 181) is midway between rewind drive pulley (R - 348) and flywheel (A - 101) when control is in " stop " position, (1.0, the travel anould be ogurl in other direction). To check, Operate brake laever (M - 110). Clearance of brake shoe should be the same on either Forward or Rewind.

D: The motor power switch (P - 119) 1s set in " Stop " position 90 that contacts are opened by biasing action of switch blade again at bakelite pin in motor swing plate. The Erase " Safety " Switch is mounted in the " stop " position so that contacts are open and a gap of approx. 1/16 " appears between motor mounting assembly (A - 112) and insulating bushing on switch, Switch is adjusted to wake firm contact when control lavor 1 In " Forward " position.

E: Forward atop lug (M - 109) should be set so motor mounting 898 bly. (A - 112) como s to rest against it as soon as drive roller (A - 181) kos firm contact with flywheel (A - 181). Excessive pressure against flywheel prevents motor from starting when control lavor 1. " snapped " into " Forward " position. Insufficient pressure results in slippage and " Wow ". Best is to adjust forward stop lug (M - 109) 1/16" from edge of swing plate at point were drive roller begins to touch flywheel.

F: There is no rewind-stop adjustment, howoves, rewind drive pulley is located in a hanger adjustable by bending stop lug (M - 111) Against the swing plate bushing, allowing a clearance between drito roller and rewind pulley in " Stop " position which allows drive roller to engage drive pulley in " Rewind " position. In this position, the rewind drive pulley hanger (A - 111) is away from the atop, prosaing drive roller by means of the torsion spring which needs no adjustment. G: Set the pressure lever (A - 113) so that it is vertical when the control knob Is in the PLAY - RECORD position. Set the arn ad Just 192, plate (M - 105) in that it closes the pressure arm (M - 104) by 1/64 when in this position. Normally adjusted, the tape guide (A - 105) will move slightly or not at all, when control is turned from Off to Rewind.

H: The brake spring (P - 116) should be adjusted so that brake (A - 114) clears take-up pulley (R - 348) and allows it to turn rooly in forward or rewind positions. The in Off or Stop

positions should be sufficient to prevent " coasting " of the reel. If brake clearance is unequal in forward or rewind, adjustment " C " is incorrect.

I: The tape guide block (A - 105) is self locating. Tape pressure pads (A - 103) located in this block are pressed forward by phosphor bronze pressure springs. These springs exert 15 grams pressure when not against the tape, and a maximum of 30 grams when in operating position with tape against the springe in guide block

J: Adjust head pressure with two screw in slotted holes in head bracked (M - 116). Both record head (A - 106) and erase head (A - 107) are adjusted into the tape guide block until the pressure pads on the reverse side show a movement slightly less than 1/32 ". This will give the 30 grams head pressure against the shoe for each head. " Wow " will result if too much pressure is used at this point.

K: Lateral movement of the heads is affected by moving them in desired direction by moans of the screws in slotted holes that hold heads to head bracket. They should be positioned so there is no hanging up of the tape pressure guide when control lever is turned to stop position, Final adjustment on record head is made by turning head so that air gap in lamination is at right angle: to direction of tape travel. This is best accomplished with the aid of a pre-recorded, constant 3000 cycle note, Adjustment is made by rotating head for maximum response on an output motor.

L: Open record or erase heads must be replaced completely. Worn out or damaged head lamination can be replaced as follows: Remove head and (M - 116) bracket assembly without disturbing the individual heads. On record head (A - 106) remove lamination (P - 127) by prying with screwdriver. Press in new lamination with fingers until it bottoms on yoke. Erase head (A - 107) lamination (P - 128) is replaced in same way. It is important to replace laminations with steel section uppermost in tape guide.

SERVICE TIPS

1. RECORDER " WOWS "
a. Felt pressure pad (A - 103) worn.
b. Dirt on drive roller (A - 181; or pressure roller (A - 183)
c. Head pressure too great. Loosen screws holding head mounting bracket (M - 116) and lower head slightly. Adjustment " L ". Do not disturb head alignment adjustment " M. "
d. Insufficient pressure on pressure roller (A - 183). Tighten spring (P - 114) or replace roller.
e. Drive or pressure roller eccentric.
f. Motor Shaft binding. Shaft should turn freely when rotated by hand with control at morr ". If necessary realign bearings by tapping motor 11ghtly with wooden tallet.

2. MOTOR RUNS BUT MECHANISM WILL NOT OPERATE
a. Motor stop improperly adjusted. See adjustment " G ".
b. Drive roller worn or defective. Replace

3. MECHANISM RUNS FORWARD BUT WILL NOT REWIND OR VICE - VERSA
a. Rewind belt (P - 112) or take-up bolt (R1) broken or off pulleys. Replace.
b. Motor stop improperly adjusted. See adjustment " G ".
c. Pressure roller interferes with panel, at Rewind. Remove roller and chamfer its bottom edge 1/16 " x 450.

4. TAKE - UP REEL DOES NOT TURN OR DRAGS
a. Brake dragging: See adjustment "H"
b. Take-up bolt (P - 113) broken, or off pulley Replace belt.

5. MECHANISM DOESN'T OPERATE WHEN CONTROL IS SNAPPING INTO PLAY / RECORD OR REWIND
a. Motor stop improperly adjusted. See adjustment "
b. Housing screw hangs up lever ar mon Rewind. Check screw length. Should be 15/16 "

6. CONTROL KNOB TURNS BUT MOTOR ASSEMBLY DOES NOT SWING
a. Motor transfer lever (A-110) set screws loose, Tighten Screws. See adjustment " C ".
b. Lever loose at hub. Replace.

7. MOTOR ASSEMBLY SWINGS, MECHANISM OPERATES, BUT NO DETENT OPERATIONS

8. SLOW SPEED
a. Pressure arm springs (P - 114) weak. Replace.
b. Head pressure too great. Raise head slightly. See adjustment " J ".
c. Flywheel shaft binding. Check tightness of screws holding front and rear plates. Check plates for warpage.
d. Motor shaft binding. Realign bearings,

2. HIGH BACKGROUND NOISE (HISS)
a. Check tape
b. Defective Record - Playback head. Replace.
c. Record head magnetized. Demagnetize with 60 cycle A.C. Air core coil.

10. INCOMPLETE ERASE
a. Erase voltage too low.
b. Erase head open.
c. Poor contact on Play - Record switch.

11. POOR HIGH FREQUENCY RESPONSE
a. Head gap not at right angles to tape. See adjustment " K ".
b. Defective head or worn lamination. See adjustment " L ".
c. Poor head contact due to worn felt pressure pad. See adjustment " J ".

AMPLIFIER SERVICE NOTES

MICROPHONIC OR NOISY ON PLAYBACK: Check 6J7 tube for noise by tapping. Replace. Microphonic checks should be made with the instrument fully warmed up.

DISTORTION ON PLAYBACK
a. Check all tubes.
b. Be sure when recording that recording light is barely flashing. An overloaded signal will cause distortion on playback.
c. Tone control should be at full treble when recording. Adjust only on playback.
d. Check all record and erase voltages as indicated on circuit diagram.
e. Be sure to check microphone plug for shorts, breakage or grounding,

MECHANICAL ASSEMBLY PARTS LIST

HEAD AND TAPE GUIDE DETAIL
M-101 FRONT PLATE

M - 101 FRONT PLATE (Rear View)

A-112 MOTOR MOUNTING