Ir a la página of
manuales de instrucciones parecidos
-
Projector
Benq MP720p
64 páginas 3.32 mb -
Projector
BenQ MW851UST
67 páginas 6.05 mb -
Projector
BenQ SP840
71 páginas 4.79 mb -
Projector
BenQ SH910
89 páginas 8.28 mb -
Projector
BenQ MX812ST
79 páginas 6.92 mb -
Projector
BenQ PE5120
26 páginas 2.98 mb -
Projector
BenQ MX761
77 páginas 6.92 mb -
Projector
BenQ model gp1
56 páginas 5.04 mb
Buen manual de instrucciones
Las leyes obligan al vendedor a entregarle al comprador, junto con el producto, el manual de instrucciones BenQ MX815ST. La falta del manual o facilitar información incorrecta al consumidor constituyen una base de reclamación por no estar de acuerdo el producto con el contrato. Según la ley, está permitido adjuntar un manual de otra forma que no sea en papel, lo cual últimamente es bastante común y los fabricantes nos facilitan un manual gráfico, su versión electrónica BenQ MX815ST o vídeos de instrucciones para usuarios. La condición es que tenga una forma legible y entendible.
¿Qué es un manual de instrucciones?
El nombre proviene de la palabra latina “instructio”, es decir, ordenar. Por lo tanto, en un manual BenQ MX815ST se puede encontrar la descripción de las etapas de actuación. El propósito de un manual es enseñar, facilitar el encendido o el uso de un dispositivo o la realización de acciones concretas. Un manual de instrucciones también es una fuente de información acerca de un objeto o un servicio, es una pista.
Desafortunadamente pocos usuarios destinan su tiempo a leer manuales BenQ MX815ST, sin embargo, un buen manual nos permite, no solo conocer una cantidad de funcionalidades adicionales del dispositivo comprado, sino también evitar la mayoría de fallos.
Entonces, ¿qué debe contener el manual de instrucciones perfecto?
Sobre todo, un manual de instrucciones BenQ MX815ST debe contener:
- información acerca de las especificaciones técnicas del dispositivo BenQ MX815ST
- nombre de fabricante y año de fabricación del dispositivo BenQ MX815ST
- condiciones de uso, configuración y mantenimiento del dispositivo BenQ MX815ST
- marcas de seguridad y certificados que confirmen su concordancia con determinadas normativas
¿Por qué no leemos los manuales de instrucciones?
Normalmente es por la falta de tiempo y seguridad acerca de las funcionalidades determinadas de los dispositivos comprados. Desafortunadamente la conexión y el encendido de BenQ MX815ST no es suficiente. El manual de instrucciones siempre contiene una serie de indicaciones acerca de determinadas funcionalidades, normas de seguridad, consejos de mantenimiento (incluso qué productos usar), fallos eventuales de BenQ MX815ST y maneras de solucionar los problemas que puedan ocurrir durante su uso. Al final, en un manual se pueden encontrar los detalles de servicio técnico BenQ en caso de que las soluciones propuestas no hayan funcionado. Actualmente gozan de éxito manuales de instrucciones en forma de animaciones interesantes o vídeo manuales que llegan al usuario mucho mejor que en forma de un folleto. Este tipo de manual ayuda a que el usuario vea el vídeo entero sin saltarse las especificaciones y las descripciones técnicas complicadas de BenQ MX815ST, como se suele hacer teniendo una versión en papel.
¿Por qué vale la pena leer los manuales de instrucciones?
Sobre todo es en ellos donde encontraremos las respuestas acerca de la construcción, las posibilidades del dispositivo BenQ MX815ST, el uso de determinados accesorios y una serie de informaciones que permiten aprovechar completamente sus funciones y comodidades.
Tras una compra exitosa de un equipo o un dispositivo, vale la pena dedicar un momento para familiarizarse con cada parte del manual BenQ MX815ST. Actualmente se preparan y traducen con dedicación, para que no solo sean comprensibles para los usuarios, sino que también cumplan su función básica de información y ayuda.
Índice de manuales de instrucciones
-
Página 1
MX815ST/MX815ST+/MX816ST/ MW817ST Digital Pr ojector User Manual[...]
-
Página 2
Table of contents 2 Ta b l e o f c o n t e n t s Important safety instructions ........................... 3 Introduction .......................... 7 Projector featu res .......... ........... ............ .... 7 Shipping content s ................. ............... ...... 8 Projector exte rior view ............. ............ .. 9 Controls and func[...]
-
Página 3
Important safety inst ructions 3 Impor tant safety instructions Y our projector is designed and tested to meet the latest st andards for safety of information technology equipment. Howev er , to ensur e safe use of this product, it is important that you follow the instructions mentioned in th is manual and mark ed on the pr o duct. Safety Instructi[...]
-
Página 4
Important safety inst ructions 4 Safety Instructions (Continued) 7. The lamp becomes extr emely hot during operation. Allow the pr ojector to cool for appro xima tely 45 minutes prior to removing t he lamp assembly for r eplacement. 8. Do not operate lamps beyo nd the rated lamp life. Excessive operation of lamps bey o nd the rated life could cause[...]
-
Página 5
Important safety inst ructions 5 Safety Instructi ons (Continued) 13. Do not place this projector in an y of the following envir onments. - Space that is poorly ventilated or confined. Allow at least 50 cm clearance fr om walls and free flo w of air aroun d the projector . - Locations where te mperatur es may become excessively high, such as the in[...]
-
Página 6
Important safety inst ructions 6 Safety Instructi ons (Continued) 17. Do not step on the projector or place any objects upon it. Besides pr obable ph ysical damage to the projector , doing so ma y result in accident s and possible injur y . 18. Do not place liquids near or on the projector . Liquids spill ed into the projector ma y cause it to fail[...]
-
Página 7
Introduc tion 7 Intr oduction Pr ojector featur es The projector integrates high-perf ormance op tical engine pr ojection and a user -friendly design to deliver high r eliability and ease of use . The pr ojector offers the fol lowing f eatures. • Network Settings allowing management of pr ojector status from a computer using a web br owser • EC[...]
-
Página 8
Introduction 8 Shipping contents Carefull y unpack and verify that y ou hav e all of the items shown belo w . If any of these items are missing, please contact y our place of purchase. Standard accessories The supp lied accesso ries will be suitable fo r your region, and ma y differ from those illustrated. *The warranty card is only supplied in som[...]
-
Página 9
Introduc tion 9 Pr ojector exterior view 1. Lamp cover 2. External contro l panel (See "Contr ols and funct ions" on page 10 for details.) 3. V ent (heated air exhaust) 4. Quick-release button 5. Focus ring 6. V ent (cool air intak e) 7. Speaker grill 8. Front IR r emote sensor 9. Pr ojection lens 10. Lens cap 11. A C power jack 12. Rear [...]
-
Página 10
Introduction 10 Contr ols and functions Pr o jector 6. TEMP eratur e warning light Lights up red if the projector's temperatur e becomes too high. 7. PO WER indicator light Lights up or flashes when the projector is under operation. 8. Keys t on e / Ar row key s ( / U p, / Do wn) Manually corrects distorted images resulting fr om an angled pro[...]
-
Página 11
Introduc tion 11 Remote contr ol 1. POWER T oggles the pr ojector between standby mode and on. 2. Fr ee ze Freezes the pr ojected image . 3. Left 4. SMART ECO Displa ys the lamp mo de selection bar . 5. ECO BLANK Used to hide the screen pictur e . 6. Digital Zoom (+, -) Magnifies or r educes the projected pictur e size. 7. Volume +/- Adjusts the so[...]
-
Página 12
Introduction 12 Remote contr ol effective range Infra-Red (IR) r emote control sensors ar e located on the fron t and back of the pr ojector . The remote control must be held at an angl e within 30 degr ees perpendicular to the projector's IR r emote control sensors to function correctl y . The distance between the remote contr ol and the sens[...]
-
Página 13
Positioning your project or 13 P ositioning y our projector Choosing a location Y our projector is designed to be installed in one of four possible in stallation loca tions: Y our room la yout or personal prefer ence will dictate which installation locatio n you select. T ake into consideration the size and position of y our screen, the lo cation o[...]
-
Página 14
Positioning your project or 14 Obtaining a pr eferr ed pr ojected image size The distance from the pr ojector lens to the screen, the zoom setting, and the video format each factors in the p rojected image size. Pr ojection dimensions Refer t o "Dimensions" on page 54 for the center of lens dimensions of this projector befor e calculating[...]
-
Página 15
Positioning your project or 15 MW817ST The screen aspect ratio is 16:10 and the pr ojected picture is 16:10 For example, if you are using an 120-inch scr een, the recommended pr ojection distance is 1263 mm and the vertical offset is 81 mm. If your measur ed projection distance is 2.5 m (2500 mm), the closest match in the "(b) Distance fr om s[...]
-
Página 16
Connection 16 Connection When connecting a sig nal sour ce to the projector , be sure to: 1. T urn all equipment off befor e making any connections. 2. Use the corr ect signal cables for each sour ce . 3. Ensure the cables are firml y inserted. • In the connections shown below , some cables ma y not be included with the projector (see "Shipp[...]
-
Página 17
Connection 17 • Many notebooks do not turn on their external vide o ports when connected to a projector . Usually a ke y combo like FN + F3 or CR T/LCD key turns the extern al display on/off. Locate a function k ey labeled CR T/ LCD or a function key with a monitor symbol on th e notebook. Press FN and the labeled function ke y simultaneously . R[...]
-
Página 18
Operat ion 18 Operation Star ting up the pr ojector 1. Plug the power cor d into the projector and into a powe r outlet. T urn on the power outlet switch (where fitted). Check that the PO WER in dicator light on t he projector lights orange after power has been applied. Please use the original accessories (e.g. pow er cord) only with the device to [...]
-
Página 19
Operation 19 Adjusting the pr ojected image Adjusting the pr ojection angle The projector is equipp ed with 1 quick-release ad juster foot and 1 r e ar adjuster foot. These adjusters change the ima ge height and projection angle. T o adjust the projector: 1. Press the quick-releas e button and lift the front of the pr ojecto r . Once the image is p[...]
-
Página 20
Operat ion 20 Corr ecting k eystone K eystoning ref ers to the situation w here t he pr ojected image is noticeabl y wider at either the top or bottom. It occurs when the pr o j ector is not perpendicular to the screen. T o corr ect this, you will need to manually corr ect it following ONE of these steps. • Using the r emote control Press / on th[...]
-
Página 21
Operation 21 Using the menus The projector is equipp ed with On-Scr een Displa y (OSD) menus for making various adjustment s and settings. Below is the ov erview of the OSD menu. The following example describes ho w to set the OSD language. 1. Press ME NU/EX IT on the pr ojector or remote contr ol to turn the OSD menu on. 3. Press to highlight Lang[...]
-
Página 22
Operat ion 22 Securing the pr ojector Using a security cable lock The projector has to be installed in a safe pl ace to prev ent theft. Otherwise , purchase a lock, such as the K e nsington lock, to secur e the pr ojector . Y ou can locate a K ensington lock slot on the rear side of the pr ojector . See item 25 on page 9 for details. A K ensington [...]
-
Página 23
Operation 23 If you f orget the passw ord If the passw ord function is activated, y ou will be ask ed to enter the six-digit password e ver y time you turn on the projector . If you enter the wrong passw ord, the passw ord error message as pictur ed to the right displa ys lasting for 3 seconds, and the INPUT PA S S W O R D message follows. Y ou can[...]
-
Página 24
Operat ion 24 Changing the passw o rd 1. Open the OSD menu and go to the SYSTEM SETUP: Advanced > Security Settings > Change Passwor d men u. 2. Press MODE/ ENTER . The message “INPUT CURRENT P ASSW ORD” appears. 3. Enter the old passw ord. i. If t he password is cor rect, another message “INPUT NEW P ASSW ORD” displa ys. ii. If the p[...]
-
Página 25
Operation 25 Switching input signal The projector can be connected to multiple de vices at the same time. Howev e r , it can only displa y one full screen at a time. When star ting up, the pr ojector a utomatically searches for the a vailable signals. Be sure the Quick Auto Search function in the SOURCE menu is On if you want the projector to autom[...]
-
Página 26
Operat ion 26 Magnifying and sear ching for details If you need to find th e details on the proje cted picture, magnify the picture. Use the direction ar ro w ke ys for navigatin g the picture. • Using the remote control 1. Press Digital Zoom+/- to display the Zoom bar . Press Digital Zoom+ to magnif y the center of the picture. Pres s the ke y r[...]
-
Página 27
Operation 27 About the aspect ratio • In the pictures b elow , the black portions are inac tiv e areas and the white portions are active ar eas. • OSD menus can be displayed on those unused black areas. 1. Auto : Scales an image proportionally to fit the pr ojector's native resolution in its horizontal or vertical width. This is suitable f[...]
-
Página 28
Operat ion 28 Optimizing the image Using W all Color In the situation wher e you ar e pr ojecting on to a colored surface such as a painted wall which ma y not be white, the W all Color featur e can help correct the pr ojected picture’ s colors to pre vent possible color difference betw een the sour ce and projected pictur es. T o use this functi[...]
-
Página 29
Operation 29 6. Press to select a men u item to be ch anged and adjust the value with / . See "Fine-tuning the image quality in user modes" below for details. 7. When all settings ha ve been done, highlight Save Settings and press MODE/ ENTER to store the sett ings. 8. The confirmation message “ Setting Sav ed ” displa ys. Fine-tuning[...]
-
Página 30
Operat ion 30 There ar e many differ ent shades that ar e cons idered to be "white" for various purposes. One of the common methods of r epresenting white color is known as the “co lor temperature”. A white color with a low color temperature appears to be reddish white. A white color with a high color temperature appe ars to ha ve mor[...]
-
Página 31
Operation 31 Saturatio n is the amount of that color in a video picture. Lower settings pr oduce less saturated colors; a setting of “0” remo ves that color fr om the image entire ly . If the saturation is too high, that color will be overpow ering an d unrealistic. 6. Press to highlight Gain and adjust its values to your pref erence b y pres s[...]
-
Página 32
Operat ion 32 T o cancel the timer , perform the followin g steps: 1. Go to the SYSTEM SETUP: Basic > Presentation Timer men u and highlight Off . Press MODE/ ENTER . A confirmation message displa ys. 2. Highlight Ye s and pr ess MODE/ENTER to confirm. Y ou will see the message “ Timer is Off ” displaying on the screen. Remote paging operati[...]
-
Página 33
Operation 33 2. Highlight Ye s and pr ess MODE/ENTER to confirm. T o release panel k ey lock, use the remote control to enter the SYSTEM SETUP: Basic > Panel Key Lock menu and press / to select Off . • K eys on the remote contr ol are still ac tiv e when panel k ey lock is enabled. • If you press POWER to turn off the projector without disab[...]
-
Página 34
Operat ion 34 T urning off the Power On/Off Ring Tone T o turn off the ring tone: 1. Repeat steps 1-2 abo ve. 2. Press to highlight Power On/Off Ring To ne and pr ess / to select Off . The only wa y to change Power On/Off Ring Tone is setting On or Off here. Setting the sound mute or changing the sound level will not affec t the Power On/Off Ring T[...]
-
Página 35
Operation 35 Menu operation Menu system Please note that the on-screen displa y (OSD) menus var y according to the signal type selected and the projector model y ou are usin g. Main menu Sub-menu Options 1. DISPLAY Wall Color Off / Light Yel low / Pink / Light Green / Blue / Blackboard Aspect Ratio Auto / Real / 4:3 / 16:9 / 16:10 Keystone Position[...]
-
Página 36
Operat ion 36 Main menu Sub-menu Options 4. SYSTEM SETUP: Basic Presentation Timer Timer Period 1~240 minute s Timer Display Alwa ys/1 min/2 min/3 min/Nev er Timer Position T op- Left/Bottom-Left/T op-Right/ Bottom-Righ t Timer Counting Direction Count Down /Count Up Sound Reminder On / Off On / Off Language Projector Position Front Table / Rear Ta[...]
-
Página 37
Operation 37 Note that the menu items ar e available when th e projector detects at least one valid signal. If there is no equipment connected to the pr ojector or no signal detected, limited menu items are accessible. Main menu Sub-menu Options 5. SYSTEM SETUP: Advanced High Altitude Mode On / Off Audio Settings Mute On / Off Volume Power On/Off R[...]
-
Página 38
Operat ion 38 Description of each menu Function Description Wall Color Corre cts the pr ojected picture’ s color when the pr ojection surface is not white. See "Using W all Color" on page 28 for details. Aspect Ratio There are sev eral options to set the image's aspect ratio depending on your input signal source. See "Selectin[...]
-
Página 39
Operation 39 Function Description Teaching Template Pro vides sev eral preset patterns for various teaching purposes. Choose Blackboard or Whiteboard first by pres sing / and press / to choose the pattern y ou need. Press MO DE/ENTER to activate the pattern. Picture Mode Pre-defined pictur e modes are pr ovided so you can optimize y our projector i[...]
-
Página 40
Operat ion 40 Function Description Quick Auto Search See "Switching input signal" on page 25 for details. Color Space Conversion See "Changing Color Space " on page 25 for details. Presentation Timer Reminds the presenter to finis h the pr esentation within a certain time frame. See "Setting the presentation timer" on [...]
-
Página 41
Operation 41 Function Description Operation Settings Direct Power On Allows the projector to turn on au tomatically once the power is f ed through the pow er cord. Signal Power On Sets whether to turn the projector directly on without pr essing the PO WER k ey on the projector when the projector is in standby mode and the signal is feed thr ough th[...]
-
Página 42
Operat ion 42 Function Description High Altitude Mode A mode for operation in high altitude areas. See "Operating in a high altitude envir onment" on page 33 for det ail s. Audio Settings Mute Volume Power On/Off Ri ng Tone See "Adjusting the sound" on page 33 for details. Lamp Settings Lamp Mode See "Setti ng Lamp Mode as [...]
-
Página 43
Operation 43 Function Description Standby Settings Network Selecting On enables the function. The projector is able to pr ovide the network function when it is in standby mode. Monitor Out Selecting On enables the function. The pr ojector can output a V GA signal when it is in s tandby mode and the COMPUTER 1 jack is corr ectly connected to devices[...]
-
Página 44
Operat ion 44 Function Description Current System Status Source Shows the current signal source. Picture Mode Shows the s elected mode in the PICTURE menu. Resolution Shows the nativ e resolution of the input signal. Color System Shows input system format: NTSC, P AL, SEC AM, YUV , or RGB. Equivalent La mp Hour Displa ys the number of hours th e la[...]
-
Página 45
Maintenance 45 Maintenance Car e of the projector Y our projector needs little maintenance. The on ly thing y ou need to do on a regular basis is to keep th e lens and case clean. Nev er remove an y parts of the projector except the lamp . Contact your dealer if other parts need replacing. Cleaning the lens Clean the lens whenev er you notice dirt [...]
-
Página 46
Maintenance 46 Lamp information Getting to know the lamp hour When the projector is in operation, the durati on (in hours) of lamp usage is automatically calculated by the built-in timer . See "Setting Lamp Mode as Economic" below for more inf ormation on Economic mode. T o obtain the lamp hour information: 1. Press MENU/EXIT a nd then pr[...]
-
Página 47
Maintenance 47 Timing of r eplacing the lamp When the Lamp indicat or lights up r ed or a message appears suggesting i t is time to replace the lamp , please install a new lamp or consult your dealer . An old lamp may cause a malfunction in the pr ojector and in some instances the lamp ma y explode. Go to http://lamp .benq.com for a r eplacement la[...]
-
Página 48
Maintenance 48 Replacing the lamp • T o reduce the ri sk of electrical shock, alwa ys turn the projector off and disconnect the power cor d before changing the l amp. • T o reduce the risk of sev e re burns, allow the pr ojector to cool for at least 45 minutes before r eplacing the lamp. • T o reduce the risk of injuries to fingers and damage[...]
-
Página 49
Maintenance 49 15. Connect the pow e r and r estart the projector . Do not turn the power on with the lamp cover r emoved. 8. Use the handle to slow ly pull the lamp out of the projector . • Pulling it too quickly ma y cause the lamp to break and scatter brok en glass in the projector . • Do not place the lamp in locations where water might spl[...]
-
Página 50
Maintenance 50 Resetting the lamp timer 16. After the startup logo , open the On-Sc reen Displa y (OSD) menu. Go to the SYSTEM SETUP: Advanced > Lamp Settin gs menu. Pr ess MODE/ENTER . The Lamp Settin gs page displa ys. Highlig ht Reset Lamp Timer . A wa rning message is displa yed asking if you want to r eset the lamp timer . Highlight Reset a[...]
-
Página 51
Maintenance 51 Indicators Light Status & Description Po w e r e v e n t s Off Off Orange Stand-by mode. Off Off Green Flashing Power in g u p. Off Off Green Normal operation. Off Off Orange Flashing • The pr ojecto r needs 90 seconds to cool down as it was abnormally shut down without the normal cooling down pr ocess. • The pr ojecto r need[...]
-
Página 52
Troubleshooting 52 T r oubleshooting The projector does not turn on. No picture Blurr ed image Remote contr ol does not work The passw ord is incorrect Cause Remedy There is n o pow er fr om the pow er cord . Plug the po wer cor d into the A C power jack on the pro jector , and plug the po wer cord into th e power outlet. If the power outlet has a [...]
-
Página 53
Specificatio ns 53 Specifications Pr ojector specifications All specifications ar e subject to change without notice . Optical Resolution (MX815ST/MX815ST+/MX816ST) 1024 x 768 XGA (MW817ST) 1280 x 800 WXGA Display system 1-CHIP DMD Lens F/Number F = 2.6 Lamp 210 W lamp Electrical Power supply AC100–240V , 3.2 A, 50-60 Hz (Automatic) Power consump[...]
-
Página 54
Specifications 54 Dimensions 287.3 mm (W) x 114.4 mm (H) x 232.6 mm (D) Ceiling mount installation 287.3 232.6 114.4 62 62 445.95 397.90 364.40 83.38 141.88 232.6 123.0 78 287.3 207.6 77 76.5 34.5 199.6 Ceiling Mount screw: M4 x 8 (Max L = 8 mm) Unit: mm[...]
-
Página 55
Specificatio ns 55 W a ll mount installation Minimum installation r equirements Computer Resolution : XGA Image Resolution : XGA Diagram Reference SMAR T Board 660 Smart Board 680 Promethean ActivBoard 164 Promethe an ActivBoard 178 RM ClassBoard2 77.5 Hitachi StarBoard FX-63 StarBo ard FX-77 Image Diagonal (inches) D6 4 7 7 6 4 7 8 7 8 6 3 7 7 Ima[...]
-
Página 56
Specifications 56 Computer Resolution: WXGA Imag e Resolution: WXGA Diagr am Refer ence SMAR T Board 685 Promethean ActivBoard 387 Hitachi FX-TRIO- 88W Hitachi FX-DUO- 88W Imag e Diagonal (inches) D8 7 8 7 8 8 8 8 Imag e Height (mm) H 1171 1171 1181 1181 Imag e Width (mm) W 1874 1874 1887 1887 Distance from floor to bottom of image (mm) f 900 900 9[...]
-
Página 57
Specificatio ns 57 Minimum Ceiling Height (mm) = f + H + b + 60 + 274+ c • The dimensions are ba sed on the BenQ wall mo unt (P/N: 5J.J4R10.001). • All measurements are a ppro ximate and may vary from the actual sizes. BenQ recomme n ds that if you intend to permanen tly install the projector , you shou ld physically test the pr ojection size a[...]
-
Página 58
Specifications 58 Timing char t Suppor ted timing for PC input • *Supported timing for non-3D and 3D signal with Frame Sequential and T op-Bottom for mat. ** Suppor ted timing for non-3D and 3D signal with Frame Sequential forma t. *** Suppor ted timing for non-3D and 3D signal with Top-Bottom forma t. Resolution Mode Ve r t i c a l Fr equency (H[...]
-
Página 59
Specificatio ns 59 • The timings showing above ma y not be suppor ted due to EDID file and V GA graphic card limitations. It is possible that some timings cannot be chosen. Suppor ted timing for HDMI (HDCP) input • * Supported timing for non-3D and 3D signal with Frame Sequential and Top-Bottom format . ** Suppor ted timing for non-3D and 3D si[...]
-
Página 60
Specifications 60 • The timings showing above ma y not be su pported due to EDID file and V GA graphic card limitations. It is possible that some timings cannot be chosen. Displaying a 1080i(1125i)@60Hz or 1080i(1125i)@50Hz si gnal ma y result in slight image vibration. ** Supported timing for non-3D and 3D signal with Frame Sequential forma t. S[...]
-
Página 61
Warranty and Copyright informatio n 61 W arranty and Cop yright information Limited warranty BenQ warrants this pr oduct against any de fects in material an d workman s hip , under normal usage and storag e. Proof of pur chase date will be required with an y warranty claim. In the ev ent this product is found to be defective within the war r an ty [...]