Onkyo DX-V500 Laser Disc Player - weird SMPS fault

[dkneyle]

This relic from a technology path that came to a dead end (but still has historical interest) was brought in with a dead SMPS, which is based around a MK1210 device. I got it going after a battle. It seems to have a strange design - if it's not getting feedback that the secondary is OK it cause the big FET to go into full conduction and overloads resulting in a blown fuse at best or something worse! I'm using a Dim Bulb Tester (70W/230V) which thankfully has saved the day a number of times whilst repairing.

Now, it loads a CD OK. The motor voltage output (which is built onto the SMPS board) reads about 3.5VDC whilst the spindle motor is turning.

Things get nasty with a considerable heavier laser disc. As the spindle motor starts to turn the SMPS drops its bundle, the DBT goes into full brilliance and the SMPS buzzes softly. Shut off mains and it restarts OK again.

I haven't risked trying it without the DBT in series. Should I risk it? Could it just be that the motor start current is causing the DBT to make the SMPS fail?

By the way, the fluro display is also no-go. This picks up AC from the SMPS transformer. I haven't gone in to measure if it is producing AC; it's pretty simple, I assume it is.

I'm a bit at a loss with this one. Normally having got a SMPS going it is plain sailing from there.

[dkneyle]

Re: Onkyo DX-V500 Laser Disc Player - weird SMPS fault

UPDATE: I took the risk and plugged directly into 230VAC. Laser disc spins up all OK. It appears the DBT was preventing the initial surge current required and tripping the SMPS into fault mode.

The Unit still has a couple of issue I may or may not be able to sort out. Upon startup the sled motor makes whining sounds and won't move the sled. Give it a couple of reload attempts and it comes good.

Also the flouro display needs to be sorted as to what is happening there.