Hitachi AX-M82D CD/DAB/FM/Cassette.
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From: ian field on 2 Mar 2010 12:06 It was dead when I got up this morning, only the standby LED was lit, pressing the power button produces a brief illumination of the backlight and a faint thump in both speakers, on initial inspection I spotted a bulged electrolytic through the vent grille on the R/H side. When I contacted Hitachi UK, they replied that this is regarded as a throwaway item and no service data is available. Does anyone know of a schematic anywhere or any info on known stock faults? TIA.
From: Adrian C on 2 Mar 2010 12:33 On 02/03/2010 17:06, ian field wrote: > It was dead when I got up this morning, only the standby LED was lit, > pressing the power button produces a brief illumination of the backlight and > a faint thump in both speakers, on initial inspection I spotted a bulged > electrolytic through the vent grille on the R/H side. > > When I contacted Hitachi UK, they replied that this is regarded as a > throwaway item and no service data is available. Chances are they didn't make it. You'll either have to identify the OEM, or replace the electrolytic and trouble shoot with what information you can find for identifiable sections. -- Adrian C
From: ian field on 2 Mar 2010 13:47 "Adrian C" <email(a)here.invalid> wrote in message news:7v50g9Fr1oU1(a)mid.individual.net... > On 02/03/2010 17:06, ian field wrote: >> It was dead when I got up this morning, only the standby LED was lit, >> pressing the power button produces a brief illumination of the backlight >> and >> a faint thump in both speakers, on initial inspection I spotted a bulged >> electrolytic through the vent grille on the R/H side. >> >> When I contacted Hitachi UK, they replied that this is regarded as a >> throwaway item and no service data is available. > > Chances are they didn't make it. You'll either have to identify the OEM, > or replace the electrolytic and trouble shoot with what information you > can find for identifiable sections. The LCD was intermittent from new and the backlight was so dim it was often hard to tell. At least now I have an excuse to open it up and have a look.
From: Jerry G. on 2 Mar 2010 22:22 Most likely the unit was made by a subcontract assembler. They build these very cheaply, and thus it does not pay for them to support this type of product. Most consumer products are made this way. You can take the unit apart and identify the capacitor that is bulged. Then you can order a generic replacement from an electronics parts supplier. You will probably find that there is a lot more at fault than just the capacitor. Something in the circuits may be at fault that caused the capacitor to overheat. You will need the instrumentation, tools, and engineering information to be able to troubleshoot the unit. Then you will have the issue to find replacements for any specialized parts that were custom made for the manufacture. These are referred to as proprietary parts. This is very common practice with today's appliances and devices. I have seen everything from TV's through to appliances that are considered non serviceable throw-away products. Jerry G. _______________ On Mar 2, 12:06 pm, "ian field" <gangprobing.al...(a)ntlworld.com> wrote: > It was dead when I got up this morning, only the standby LED was lit, > pressing the power button produces a brief illumination of the backlight and > a faint thump in both speakers, on initial inspection I spotted a bulged > electrolytic through the vent grille on the R/H side. > > When I contacted Hitachi UK, they replied that this is regarded as a > throwaway item and no service data is available. > > Does anyone know of a schematic anywhere or any info on known stock faults? > > TIA.
From: ian field on 3 Mar 2010 09:48
"Jerry G." <jerryg50(a)hotmail.com> wrote in message news:a6be7d46-3863-476c-84a4-b3da6b58351a(a)f35g2000yqd.googlegroups.com... Most likely the unit was made by a subcontract assembler. They build these very cheaply, and thus it does not pay for them to support this type of product. Most consumer products are made this way. You can take the unit apart and identify the capacitor that is bulged. Then you can order a generic replacement from an electronics parts supplier. You will probably find that there is a lot more at fault than just the capacitor. Something in the circuits may be at fault that caused the capacitor to overheat. You will need the instrumentation, tools, and engineering information to be able to troubleshoot the unit. Then you will have the issue to find replacements for any specialized parts that were custom made for the manufacture. These are referred to as proprietary parts. This is very common practice with today's appliances and devices. I have seen everything from TV's through to appliances that are considered non serviceable throw-away products. Jerry G. The bulged capacitor was guilty as charged (excuse the pun) the ESR was over 5 Ohms - I don't have a meter to measure capacitance as big as 2200uF. However that wasn't the whole story, when I cleaned off the solder one of the capacitor's solder pads dissapeared up the solder sucker - it was as if the pad had been die-cut around the edge of the solder mask, so I had to scrape the solder mask along the track and solder a link across the hole in the copper so I had something to solder the replacement capacitor to. The only 2200uF/16V I could find was fatter than the original and as it stands between the fins of a nearby transistor's heatsink, the fatter capacitor pushed the heatsink over a bit so it fouled a nearby 100nF disc-ceramic cap. The 100nF is in parallel with the electrolytic, so I removed it and put a couple of 150nF ceramic chip capacitors I nicked from a scrap HDD logic board onto the print side. Looks like I caught the fan just in time! It was a bit stiff, so I peeled the label and squirted some GT85 PTFE freeing oil in the bearing to get it spinning again, then hooked it up to a spare 12V connector on the PC to work a few drops of Slick50 into the bearing while I was working on the rest of the unit. One thing is a little strange - after the repair I had to turn the volume down 3 presses on the down button, so obviously some part of the audio path is supplied by that PSU section which I thought only did the front panel logic board. I'm surprised that there were no disturbances or hum on the audio as the capacitor went into it's death throes. |