Philips DCC 900 Compact Cassette Recorder

[dalpaul]

Hi WornEars,

If you need of the service manual, as I can't send it by mail because of its size ( it's a pdf file of about 20 MB ) I can upload it and give you the link.

I just repaired one that had a problem, as many of the DCC900 have : no more output neither with analog, nor with digital cassets. The problem comes from the surface mount capacitors of the PW03 read write board that lose their electrolit on the printed board and sometimes burn the board copper.

Thats a very nice machine, build like a tank.

i am having the same problem of this board.

i measured the RDMUX and ANA L/R. none has any meaningful output. i checked all the voltage at each pins. they are not exactly the same as service manual but close. it is hard to believe the IC is dead.

i heard the story of dried e-cap but i have not try yet.

 

[spirou38]

i am having the same problem of this board.

i measured the RDMUX and ANA L/R. none has any meaningful output. i checked all the voltage at each pins. they are not exactly the same as service manual but close. it is hard to believe the IC is dead.

i heard the story of dried e-cap but i have not try yet.

Hi from France,

First check Vsense1 and Vsense2 voltage on the R / W board when the problem occur. I know that it is not very easy to check that !
If you have 0 Volt on those check points it’s because the SMD caps are dry and caps acid has probably burned some copper tracks.

If you have the correct Voltage on Vsense1 and Vsense2, there are a lot of possibilities, but it’s difficult to make a diagnostic without the deck. Some possibilities are : one of the flat cables is not correctly inserted ( or bad contacts, so try to clean the flat cables contacts ), or trouble on the digital card.

Have fun with your dcc.

 

[dalpaul]

hi, Spirou38

thanks for the lead.

however, i can not figured out which pin is refer to Vsense1/2.

i only have philips TDA1317 datasheet and Technics RS-DC10 service manual.

would you please elaborate little on those too pins? for example, which # they are refer to?

what i guess is pin 10/9 of ref1/2 as ref2 served as switch between dcc and acc amplifier.

i fully agree the e-cap at pin 10/22/35 are served as AC feedback decoupling capacitor. if they dried out, the gain of each amplifier would be degraded.

however, if this is true. then the whole unit might facing the same problem as it is hard to believe only the e-cap on this head amplifier board dried out.

thanks

 

[dalpaul]

a good new i like to share with you.

the DCC 900 has been fix.

the reason is one trace from pin 14 of J103, which is 8V to Q102/3/4 was broken.

these 3 transistors are supplying bias to the head.

it is thus simply.

although electrolytic capacitors still function but i had ordered some tantalum SMD capacitors to replace them.

a fact that i need to mention is there is some strange smell from the machine when i open the cover. it is very hard to forget.

i would assume this is the smell from the leaking electrolytic capacitors.

 

[plugandpray]

:thmbsp:

 

[booted]

Just got one of these decks today. Worked for a while. And the drive gear ears broke. And the just play back side gears are weak also. Such brittle plastic.

 

[booted]

update. Got new gears for philips fc 930 cassette deck. back working again.

 

[Bone Yard]

Thanks for pulling this thread back up, those links are priceless!

I think there's some videos on YouTube, maybe Techmoan or VWestlife, with similar issues and having to get a few units to fix one. Luckily in the Walkman World a few crafty individuals have remade the center plastic gear that also cracks over time on the priceless DD Models.

Plastics were really expanding like crazy in the early 80's on, while they were a perfect fit initially, the additives ended up not working long term and they self-destructed, but now that we have much more experience, they seem to be forever.

Good luck with your DCC, I still haven't found one yet but I did pick up a killer professional Tascam DAT a few weeks back.