Sony AZ series HCR-AZ5D Power Issue

[DjKrish]

Ok i have this set for sometime now and suddenly there's problem with power. The red standby light is working, but when u press it to on the unit, its like the set is on low battery. If u press the power button again, the light comes back to red standby. If u don't press the button back again, then the red light starts flashing. Is there a problem with the power supply? Less power supplied to the main board?

Faulty power supply? Theres no display either. Only the power red light works. I thought it was cold solder joints, i re soldered everything, still same. TO check the power supply voltages, i dont have the diagram either Can anyone help pleaseeee.....

[dj_ricoh]

Re: Sony AZ series HCR-AZ5D Power Issue

open it up and post the photos here
that`s the first step

[DjKrish]

Re: Sony AZ series HCR-AZ5D Power Issue

Ok, manage to get some photos of the system. Before that, i turned it on like after a few days, the system is working fine, all display is back, power is back and everything operates as usual. Weird. But if, IF i off it at main plug and on again, the problem starts. So i doubt this is a power supply problem. So what could be the real problem in here? Please help me. If turn off for few days and on back, working fine but if off and on back, its not working anymore.

Non working state and internal parts












Working state perfectly fine

[DjKrish]

Re: Sony AZ series HCR-AZ5D Power Issue

Upon checking the voltages on the power supply, i noticed the +12v unregulated voltage and the +7.5 unregulated voltage is not accurate enough.

+12v shows +4v measurement and the +7.5v shows +2v measurement on the multimeter reading. Something is not right. Theres a MR5060 Power IC before the primary to secondary transformer. I suspect the IC could be faulty not supplying the correct voltage. Please correct me if im wrong.

The MR5060 is a INTEGRATED T-1 RESISTOR LAMPS 5 VOLT AND 12 VOLT SERIES.

[lexwalker]

Re: Sony AZ series HCR-AZ5D Power Issue

Upon checking the voltages on the power supply, i noticed the +12v unregulated voltage and the +7.5 unregulated voltage is not accurate enough.

+12v shows +4v measurement and the +7.5v shows +2v measurement on the multimeter reading. Something is not right. Theres a MR5060 Power IC before the primary to secondary transformer. I suspect the IC could be faulty not supplying the correct voltage. Please correct me if im wrong.

The MR5060 is a INTEGRATED T-1 RESISTOR LAMPS 5 VOLT AND 12 VOLT SERIES.

That's incorrect. Did you even try understanding the circuit? This MR5060 is an integrated switching power I.C (like one of those TOP series I.Cs from Power Integrations)...

[budm]

Re: Sony AZ series HCR-AZ5D Power Issue

As you notice, both 12v and 7.5v has about the same percentage of the voltage drops (both are generated by the same transformer and drive circuit), so it can be due to bad regulation feed back, bad caps (such as start up cap, filter). I also see a smaller transformer for the 5V supply (I cannot see any labeling on the dc output connectors in the pictures).

[DjKrish]

Re: Sony AZ series HCR-AZ5D Power Issue

That's incorrect. Did you even try understanding the circuit? This MR5060 is an integrated switching power I.C (like one of those TOP series I.Cs from Power Integrations)...

Hehehe thats why i said correct me if im wrong.

As you notice, both 12v and 7.5v has about the same percentage of the voltage drops (both are generated by the same transformer and drive circuit), so it can be due to bad regulation feed back, bad caps (such as start up cap, filter). I also see a smaller transformer for the 5V supply (I cannot see any labeling on the dc output connectors in the pictures).

The 12V unregulated supply comes straight from the big transformer leg. I even measured from the leg, it still shows the same voltage. So that means the voltage us not supplied enough by the transformer. Ive check both start up caps with caps meter and esr meter, both are fine. Anywhere else should i be checking?

[DjKrish]

Re: Sony AZ series HCR-AZ5D Power Issue

Additional note : The power supply also has a pq1cg203 regulator IC.

[budm]

Re: Sony AZ series HCR-AZ5D Power Issue

From the pictures I see the TRORID INDUCTOR at the bottom right, it seems to be for sub switching buck regulator power supply.
Can I get good close up pictures of the whole bottom side of the board, als0 may be 4 small sections of top and bottom side of the board so I can clearly see the traces and the components? Also there is a trimpot on the corner, did you try making the adjustmet? just make sure to mark the location of the pointer first so you can trim it back to the same location.

[DjKrish]

Re: Sony AZ series HCR-AZ5D Power Issue

[DjKrish]

Re: Sony AZ series HCR-AZ5D Power Issue

CN1 is to Amp pcb, CN2 is to main pcb.

[DjKrish]

Re: Sony AZ series HCR-AZ5D Power Issue

Ok i quite dont get it. The system works fine if i mess with the CN2 power cable supplying power to the mainboard. The set is like on low battery. If i pull out the cable and plug back doing the same thing a couple of times then the system works fine again till i switch it off at mains. Once its on, it will work fine for days till u off the mains. I doubt this is the problem in power supply. Anyone seen this issue before?

Once the set is back fine working state, the 12v+ unregulated supply is accurate and the 7.5v+ unregulated seems to be at 7v+. Something is needing a push start a couple of times to make this set work. Like a car. Could it be one of the regulators on the main pcb?

[budm]

Re: Sony AZ series HCR-AZ5D Power Issue

I have seen this problem on some of the power supply that goes in to burst mode (sleeping mode to reduce power consumption) when the current draw is very low and it was not enough to keep the power supply regulated. Try putting 100 Ohms 5W resistor at the output of the 12V (this will draw about 120mA (1.44W of power) on the 12V line and see if that will be enough load to keep the SMPS IC from going into burst mode.

[DjKrish]

Re: Sony AZ series HCR-AZ5D Power Issue

I have seen this problem on some of the power supply that goes in to burst mode (sleeping mode to reduce power consumption) when the current draw is very low and it was not enough to keep the power supply regulated. Try putting 100 Ohms 5W resistor at the output of the 12V (this will draw about 120mA (1.44W of power) on the 12V line and see if that will be enough load to keep the SMPS IC from going into burst mode.

From the smps to the socket output that goes to the main pcb right?

[Bassman]

Re: Sony AZ series HCR-AZ5D Power Issue

Now, I am in the process of learning all this, so bear with me, but it appears that a couple of your solder connections on IC101 have blown out.

[budm]

Re: Sony AZ series HCR-AZ5D Power Issue

@dj: yes, we want to put a little load on it.

[DjKrish]

Re: Sony AZ series HCR-AZ5D Power Issue

@dj: yes, we want to put a little load on it.

Tried that, no luck, still same.

[DjKrish]

Re: Sony AZ series HCR-AZ5D Power Issue

Now, I am in the process of learning all this, so bear with me, but it appears that a couple of your solder connections on IC101 have blown out.

Actually the track base broken a bit, otherwise the solder is good and intact

[DjKrish]

Re: Sony AZ series HCR-AZ5D Power Issue

Good news. Previously i ordered MR5060 and pq1cg203 IC. It just arrived yesterday. After fixing both, walla the set is back to life. No more low battery problems hehehe. Finally the set is fixed. So those 2 were the culprit.