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-   -   Beovision LX2502 manual needed? (https://www.vintage-radio.net/forum/showthread.php?t=127134)

threeseven 8th Jun 2016 5:13 pm

Beovision LX2502 manual needed?
 
Have recently put this set into service and quite like it, so I'd like to sort out a couple of issues it has, for which a manual would make easier.
Issue one, intermittent switch on fault. When turning on from standby with the remote, the standby light goes out momentarily but then comes back on with the set refusing to turn on. Repeatedly pressing the on the remote on button sometimes kicks it into life, if not then it has to be powered down, wait for 30 seconds or so, then it will normally turn on.

Issue two, when the set is first turned on, there is line instability at the bottom of the frame, particularly on bright scenes or white background. Five times out of ten this will continue and then there is a sudden pin cushion. That can be cleared by powering off and on between 1 and 4 times. If the line instability doesn't go to pin cushion, it clears and is then fine.

Also, if someone has a couple of bass drivers spare, I'd be grateful. The ones in the set have lost their surrounds.

Any help with the faults most welcome as I'm not experienced with colour sets :-[

tri-comp 9th Jun 2016 2:31 pm

Re: Beovision LX2502 manual needed?
 
With the manual I can help.
PM me with your e-mail address for a FOC pdf-copy.
About the faults I may also be able to help.
Intermittent refusal to turn on may be caused by a defective C28, 220uF electrolytic cap. feeding the Line Output Transistor BU508.
I seem to remember that replacing C29, 100uF power supply decoupling capacitor for the line output drive circuit is also a good idea.
Do a resoldering of the Horizontal Output Circuit against periodical pin cushion faults.
I would say the line instability problem you describe could also be caused by a defective electrolytic cap. just I don't know which one.

Remember to use 105 degree quality electrolytic cap's for replacement (Panasonic, Sanyo, Nichicon etc.)

threeseven 9th Jun 2016 5:09 pm

Re: Beovision LX2502 manual needed?
 
Many thanks for the PDF, I'll PM my email address.
Thanks for the ideas on the faults, C28 sounds a likely candidate as the line drive can be heard struggling. I might just recap the whole PSU, they will be past their best by now!


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