Akai 1700

Pe et
Xl
TROUBLE
SHOOTING
CHART
FOR
MODEL
1700
SECTION
“A”
TROUBLES
WITH
AMPLIFIER
1.
Playback
problems.
(Unit
set
in
play
position.)
Fuse blown
No sound from
loud speaker.
Vacuum tube(s)
\does not light.
Defective power transformer.
“; {Check and replace. i
Defective switch. |} {Check and replace.
Vacuum tube(s)
seems okay.
[Hum from loud speaker.
volume.
Sound from speaker but insufficient
Sound from speaker but with
loud hum.
No speaker hum.
Defective Via, V1b, or V2a.
[No change after tubes replaced.
Head coil burned out.
Defective top or 2nd stage tube (V1, V2)
Replace.
Defective S84, J1,P1, Rl, R16, R4, RS
heck if voltages correct, and replace resistor]
Output transformer burned out.
Speaker voice coil burned out.
Defective power output tube.
Defective R%
Replace tube.
Deposit of dust on head
Recording tape being reversed.
Check and replace.
Replace speake
Replace.
Check voltage, and replace.
Clean heads gently with cotton swab
soaked in rubbing alcohol.
:
|
B (+) voltage low.
Check and correct tape.
Check 8M150a, C20a, b, O21, 022.
Defective resistor(s) and /or capacitor(s) in circuit.
Check voltages, and replace defective one (s)
[Hum controllable with volume control.
Intermittent noise.
Defective V1 or V2.
Replace V1 or V2.
Vi, V2 input(grid) lead wires improperly positioned.
Dress reposition input lead wires.
Head, V1, V2, ground wire improperly positioned
[Dress ground wire.
|fitum not controllable with volume control
Defective vz, -}——_————_Repacee V;
Defective C26, L1 or C8, C17.
Hum reduced when playback head shorted.
H—-|
Shielding on playback head not perfect.
Replace head.
fLeakage flux from motor or from power transformer.
Check motor and power transformer,
replace if necessary.
Hum bucking coil out of adjustment,
Read just hum bucking coil.
Unit picks up external magnetic flux.
(Ground recorder at capstan storage post]
[Hum only when playing tape, no hum without tape.
Hum recorded on tape.
Noise level controllable with volume control
‘Constant background noise
from speaker.
Noise level not controllable with volume control. |
Defective V1, C5, IN, NF Circuit,
Defective
R4,
R5.
Check
Rl,
R6,R8
or
R11
and
replace.
Reposition recorder.
Shield recorder.
Defective V2,+
Defective R7
Replace V2.
Check R7.
Output transformer being burned out.
(Check and replace output transformer.
Lack of bass.
L_fNoise with or without tape on recorder.
Noise only while tape is being played.
| Taneven coating on recording tape.
Tape heads being magnetized.
Defective 05, 07, C10, R2, VR1.
eee vi, V2.
Defective Rl, R3 or R8
Check C5, G7, 010, R2, VR1.
Defective recording tape.
Replace recording tape.
Lack of treble.
Ltworn-out tape heads.
Recording tape in close contact with tape heads.
Record/play head mis-aligned. (Azimuth
alignment of gap in recording haad.)
pest on tape heads.
Weak back tension. Check supply reel shaft assembly and
Re-align head using standard alignment tape.
Sound distorted.
Defective Vi or V2.
Replace head assembly.
Ly Defective loud speaker.
Incorrect circuit rating.
Replace V1 or V2
Check component parts in circuit by mea-
|_________
suring
voltage.
See
wiring
diagram
for
re~
gular volatge.
[Replace loud speaker. |
Replace recording tape with new one.
Denagnetize heads using head demagnetizer.
Replace V1, V2.
Check R1,R3 or R6,
Clean tape heads.
readjust spring tension.