Ok, assuming yer look'n down on the PC board, with the power connector located at the top (upper left), then U should find D808 right next to Q801 (towards the direction of the power connector). It's closest to the "G" or the Gate side of Q801. It is very small, but U should be able to find it, unless U have a different version of this board. Hope this helps.

Bob

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...can't seem to find D808 diode on the board...(power pc 2700)can you give me and idea in relation to another part please..Q801 is clearly visable.

 

I changed the q801 and changed d808(is it the one from r815 and r813)and still the fuse blows.Is it possible the t801 filter cause the short..Thanks

 

Thanks Bob for reply...I don't find anything writen d808,found clearly all the other ones.I did find a diode across R815 and R813(hopefuly that one is it) and changed that one,along with q801.All that aside the board still doesnt power up and the fuse blows...I heard the t801 could cause that also/the line filter(183y0r5)..is there a way that can be tested??/I cant fin the part anywhere to purchase (Canada)Thanks guys

 

I've got a manual for the UK SD110, which sounds fairly similar - does your PSU have an 8 pin IC, Q802 a TA1319AP, and two opto-isolators?. On my circuit D808 is in parallel with D809, they go from the gate of Q801 to PSU primary ground.

 

Hi Nigel,the board is pc power 2700 and is from a Sd 1750 dvd player.I do have the 8 pin ic you mention,but again there isn't anything on gate of Q801..no d808 or d809??the ony diode without a # is across r815 and r813...and I changed that one...along with q801.....The t801 was smoking
at one time upon replacing fuse(before parts q801)so I was wondering if the t801 is testable(line filter)..thx

 

Easy to test - disconnect the bridge rectifier, put a new fuse in, plug it in. If the mains filter is S/C it will still blow the fuse.

Was Q801 faulty?, or did you change it as a matter of course?.

I can email you the PDF manual for the SD110, but it's 20MB!.

 

I changed the q801 as the suggestions of the forum,but did wind up testing it and it does fail,also wound up changing 4 diodes from d801 to d804(in4007)as 2 of them were infact short also...but still doesn't power up....although THE FUSE DOES NOT BLOW ANYMORE>>>HURRAH....so now where do I go from here....please

 

Well, as a professional service engineer, I wouldn't ever change the chopper transistor without changing the control IC as well, particularly when the transistor is an FET. The transistor going S/C commonly damages the chip.

There's probably a low value resistor in the source of the FET to ground, if the FET has failed that's likely blown as well.

As with anything else, the key to fault finding is understanding how the circuit works.

 

Well Nigel I would like to thank you for your help.You seem to be very helpful on this forum as I see all your posts..I will change the ic as it doesn't cost much and check resistor around FET.I did leave it for a professional to look at and he quoted me at $165.Canadian to repair.Its a shame that $20 of parts comes to $165....So that is why I am triing.if the Ic doesn't work....I will scrap it....Thanks again...

 

Hello,
In continuation of the earlier discussion sometime last year, I too am having the same problem with my Toshiba DVD player. I tried replacing the F801 fuse couple of times and it blew both the times. I am using a 1.6A 250V fuse and the recommended voltage is 125V. I understand it shud not make a difference, but what else can a electronics novice do to fix this problem. I have a rental dvd inside the player. Is there anyway I can remove the disc without powering it ON..? Any help is highly appreciated!
Thanks

 

Fuses don't 'really' have voltage ratings (not as far as the blowing value is concerned). It's just a guaranteed voltage it will disrupt, so a 250V rated fuse makes no difference, if anything it could be very slightly safer?.

You should be able to manually turn a gear in the DVD mech and wind the disk out - some DVD players have a hle underneath where you can insert a small lever nad open the mech (but not all).

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