please help to identify replacement diode

[debugtimog]

Hi All,
Please help me identify what is this unmarked crystal diode and how can I find its replacement partnumber.



Thank,

[stj]

Re: please help to identify replacement diode

only way to know is a schematic.
so what is the board from?

[budm]

Re: please help to identify replacement diode

Please provide the pictures of the whole board also.

[debugtimog]

Re: please help to identify replacement diode

Hi,
I have put an arrow to where the diode is, it is connected to the coil of the relay where i draw a box. At the bottom of the box is the normally open contact for the relay. The IC is lm393. This a power supply but i noticed when I plug in, the relay is not being powered on, thats why i am now focusing around this area.

[budm]

Re: please help to identify replacement diode

1) The relay coil is driven by Q22 so is Q22 good and is it being driven to turn on to supply the current to the relay coil?
2) What Voltage testing have to done so far?
What Voltage do you have on each leg of the relay coil with ref to GND?
3) Where are the pictures of the whole top and bottom side of the board?

[debugtimog]

Re: please help to identify replacement diode

Thanks budm, I traced the voltage from q22 and it leads to a voltage regulator that is undervoltage, suppose to be 14vdc(relay coil voltage rating is 15v) and i measure 4volts.replaced the regulator and it did start up the power supply.

But I still dont know what/how to replace this diode. fortunately it wasnt defective and there was no need to replace it

[R_J]

Re: please help to identify replacement diode

The diode is a minimelf diode SOD-80, The band color could identify the voltage/current etc.
Maybe a LL4150GS08

[csaba911]

Re: please help to identify replacement diode

The designation is D10 is there any other diode have ZDxx? If yes than it’s probably just a generic 1N4148. De solder it and check with a multimeter diode test, if bad than try to install new 1N4148.