Toshiba VCR / DVD blown diode?

[mikay786]

I've got a shorted SB390 diode which was in parallel with UF5408 diode.

d1031 = uf5408
d1035 = sb390

service manual pages 1-14-25 & 1-14-26

Ive found a equivalent for the SB390 in the SB3H90

what i wanted to know is it likely that the UF5408 has already been replaced?

As in originally both diodes would have been SB390s

So if i were to replace the pair could i replace both with SB3H90?

[petehall347]

Re: Toshiba VCR / DVD blown diode?

what does H mean ?

[petehall347]

Re: Toshiba VCR / DVD blown diode?

they should be matched for vf and track each other at same temperatures . failing that use just one sub of double power rating .

[mikay786]

Re: Toshiba VCR / DVD blown diode?

what does H mean ?

Not sure, seen this thread for a suitable replacement

https://www.badcaps.net/forum/showthread.php?p=533665

[mikay786]

Re: Toshiba VCR / DVD blown diode?

they should be matched for vf and track each other at same temperatures . failing that use just one sub of double power rating .

Cheers so originally both would have been SB390?

[petehall347]

Re: Toshiba VCR / DVD blown diode?

Cheers so originally both would have been SB390?

i would think so yes

[Rajnhl]

Re: Toshiba VCR / DVD blown diode?

I've got a shorted SB390 diode which was in parallel with UF5408 diode.

d1031 = uf5408
d1035 = sb390

service manual pages 1-14-25 & 1-14-26

Ive found a equivalent for the SB390 in the SB3H90

what i wanted to know is it likely that the UF5408 has already been replaced?

As in originally both diodes would have been SB390s

So if i were to replace the pair could i replace both with SB3H90?

SB3H90 diode can be used.previous . technician was unexperienced i think.
always change both diodes in parallel , if any one is short and use same type for both.

H stands for high voltage