NATIONAL |
NVAM1 |
Switchmode Supply Starts Then Stops After 2 Seconds. |
D4 Leaky |
NATIONAL |
NVAM1 |
Switchmode Supply Won't Start. |
R13 O/c Or Hr |
NATIONAL |
NVAM3 |
Switchmode Supply Starts Then Stops After 2 Seconds. |
D4 Leaky |
NATIONAL |
NVAM3 |
Switchmode Supply Won't Start. |
R13 O/c Or Hr |
NATIONAL |
NVG10 |
Colour Drop-outs And Lines. |
C1002 100uf/35v |
NATIONAL |
NVG10 |
No Channel Select, Number Indicator, Or Preset |
Check For 30v At Pin 8 Of Plug Ja. If Missing,check R7572, 47k Ohms, In The Tuner And Demodulator Section Of The Main Pcb. |
NATIONAL |
NVG10 |
See Nvg7 |
|
NATIONAL |
NVG10 |
Vtr On/off Faulty. Red Vtr Indicator Flashes When Vtr Off. |
Check For Open Circuit D1006, Ma165,near Ic 1 In Power Section Of Main Pcb. |
NATIONAL |
NVG11 |
Breaking Tapes. |
Faulty Hall Effect I.C. On Stator. |
NATIONAL |
NVG11 |
Tuning Problems With E7 Serial No Prefix. |
Change Ic7551 O7555 Q7551 Q7552 Because I.C. Legs Bend Over And S/c's Are Produced. |
NATIONAL |
NVG12 |
Damaging Edge Of Tape In Play Or Rec Modes. |
Adjust P5 Post. |
NATIONAL |
NVG12 |
Mistraking. Noise Bars In Picture. |
Replace Pinch Roller With New Part Number Vxl17433. |
NATIONAL |
NVG12 |
See Nvg7 |
|
NATIONAL |
NVG16 |
No Display, No Functions,operate Light On |
Dry Joints To Q15 Drum Heater. (series Pass For + 6v Reg.) |
NATIONAL |
NVG18 |
See Nvg7 |
|
NATIONAL |
NVG21 |
No Or Intermittent Power |
C25 & C18 (47uf 50v) O/cct In Power Supply. Low +23 To Regulator Ic. |
NATIONAL |
NVG21 |
Red Vtr Indicator On,wont Turn Off,no Clock. |
Check Volts On Pin 10 Of Ic 7551, An5034,in Ch. Select Section Of Main Pcb At Rear Of Board. Section Ref.No. 7500 Series. Pin 10, Pclr Line Goes To Pin 11 Of Ic 7502, Mn1220 On Display Pcb. |
NATIONAL |
NVG21A |
No Power.Chopper Faulty And Clicking Noise. |
Insulation Between Chopper And Power Box In Wrong Position. |
NATIONAL |
NVG22 |
Vtr Operate Light On. Vcr Function May Still Work. Clock Shuts Down. Noise On Pins 2,3,4, Of P1001(socket On Switch Mode Pwr Supply). |
Change C1023 10v 1000uf Capacitor. |
NATIONAL |
NVG25B |
Interm. Sound And Pic. Dropouts,creasing Bottom Of Tape |
Pinch Roller Barrel Shaped.See Page 61 Of V.C.R. Technical Service Information For Diagram. |
NATIONAL |
NVG25B |
Interm. Sound And Pic. Dropouts,creasing Bottom Of Tape. |
Pinch Roller Barrel Shaped. Check If The Creasing Occurrs When The Tape Moves In The Fully Laced Position. |
NATIONAL |
NVG25B |
No Video On Monitor In E-e Or Play. |
Check If Q3501 (2sc2206) O/c (2sd636 Can Be Subs.) D3502 (ma27w) O/c. |
NATIONAL |
NVG30 |
Poor Colour Or Flashing In Play. |
C2 In Power Supply Near Regulator. |
NATIONAL |
NVG40 |
No Power Dead. |
Replaced Fuse F1001. |
NATIONAL |
NVG40 |
Poor Capstan Torque, Causing Motor To Stall During Changes Of Cassette Functions And Vtr To Turn Off Intermittently |
Suspect Faulty Ic2501, Ba6432s On Sub Main Cba |
NATIONAL |
NVG40 |
When Tape Inserted At Very Beginning. Machine Ejects Tape. |
Replaced Both End Sensors. |
NATIONAL |
NVG500 |
Power Supply Fails To Start Or Restart After Power Interruption. |
C1003 1uf/350v Cap O/c. |
NATIONAL |
NVG7 |
Int Failure To Retract Tape When Unloading. |
Faulty Mode Select Switch Pt. No. Vss0110. |
NATIONAL |
NVG7 |
Int Stop In Play Mode Or Rec. Or No Take Up. |
Faulty Mode Select Switch Pt. No. Vss0110. |
NATIONAL |
NVG7 |
No Power Up At All.Reset Being Held High. |
Vr7502 Out Of Tolerance. Ajust Until Power Up. |
NATIONAL |
NVG7 |
Unit Accepts Tape Then Rejects It. |
Check End Sensors Aren't Leaky R6009 For Shorts To Surrounding Circuit. |
NATIONAL |
NVG9 |
Drum And Capstan Motors Not Locking. |
Main Regulator Ic Stk5331..12v Line Faulty. |
NATIONAL |
NVG9 |
Wont Memorize Tv Stations. |
Repalce Ic 7502 And Check Cap 7510 10µ50v |
NATIONAL |
NVH65 |
Plays Black And White. Capstan Speed Varies In Play. |
C1023 (1000uf 25v) Low Or O/cct. Excessive Ripple |
NATIONAL |
NVH70 |
Memory Of Preset Tv Stations Faulty. |
Suspect Faulty Ic 7502, Mn1220. |
NATIONAL |
NVH70 |
Memory Of Tv Stations Faulty. |
Suspect Faulty Ic7502, Mn 1220. |
NATIONAL |
NVH75 |
Drum Servo Pulses In Speed. |
C10028 (330uf/35v) Faulty. Noisy +5 And +6v Power Rails. |
NATIONAL |
NVH75 |
No Drum Or Capstan Lock, Interferance On Ee Picture |
Repalce C1028 330µ25v (use 105 Deg Cap) In Psu, It May Read Ok |
NATIONAL |
NVH75 |
No Power |
Check Q1006, 2sc1384 (r,s) In Power Cba Unit. Check Diode D1008, Ma185. |
NATIONAL |
NVM1 |
Picture Goes Green Then No Colour. |
Check Pin 12 Of Ic401 Should Be 2.5v If Higher Replace Ic401. |
NATIONAL |
NVM5 |
Noisy Audio On Playback Of Own Recordings. |
Check Isloate Dc Lead Rubbing Against Drum Motor. (picking Up Noise.) |
NATIONAL |
NVM5 |
Screen Is Brilliantly Lit Up. |
Check -5 Line Drive From Transformer Power Pack (diode Goes O/c) |
NATIONAL |
NVM5 |
Unit Turns On By It Self After A While. Also Wont Turn Off Sometimes.. |
Operate Switch Faulty.. |
NATIONAL |
NVM5 |
Unloading Is Complete. |
Because Pinch Roller Returns In Front Of Drum Exit Loading Guide, Remove Excess Grease On Cam Gear, Clean Hardened Grease Out Of Teeth Of Loading Gear. |
NATIONAL |
NVM7 |
Clock And Calender Not Functioning. |
Check For D/j's On Pin 31 Of Ic1. |
NATIONAL |
NVV10 |
Display Flickers. |
Caps C111 & C108 330 µ & 100 µ Repalce. |
NATIONAL |
NVV10 |
No Go |
Caps In Power Supply, C106 2200 µ 16 V Cap Leakie |
NATIONAL |
NVV10 |
See Nv100 |
|
NATIONAL |
VWA18 |
No Operation Or Power. |
Internal Fuse In Primary Of Mains Transformer May Go Open Circuit. Take Leads 2 From Fo1 To Bluem Wire, Pin 8 Of Voltage Select Switch, Sw02. |
NATIONAL |
VWA18 |
No Operation Or Power. |
Check For Short Circuit Diode. Diode Has No Reference Or Location Number And Is Not Shown In Service Manual Diagram. Located Next To C13 Near Large D11. |
NATIONAL |
VWA18 |
Unit Stays In Tv Mode Wont Switch To Vtr Mode. |
Check For Open Circuit R11, 39 Ohms, On Front Operation Pcb. |
NATIONAL |
VWCG1 |
See Nv-m7 |
|
NATIONAL |
VWET180 |
No Clock Display. Poss. Tuner & Vtr/tv Indicators On. |
Suspect Ic6723, Mn1512vtp, On Main Timer Pcb. |
NATIONAL |
VWET180 |
Switch Mode Noise Audible |
C105 1000uf 16v O/c Or Low Capacitance. |
NATIONAL |
WAM7A |
Not Charging Batteries |
Q101 (2sb952) Dry Joints On Base And Collector Also Broken Base Track.Ilastic Transistor Caseto Dampen Movement. |