Lighting problems on KT6500

[jimbo2k]

This appears to be a budget tuner, in the larger fomat size matching the Ka 7100,8100,9100. So much so that there is no winding on the transformer for the lights, so they most be padding down the secondary 12v winding to power the 2 dial light and the meter lights (all 8v 300 mw). Well its a dead circuit as the unit works fine just in the dark. HiFi engine has only a partial service manual with no schematic. Any suggestions?

 

[gort69]

Schematic here

 

[jimbo2k]

Thank you my friend.

 

[turboyam]

Don't quote me on this but i think the 3 bulbs are in series? so if one is burnt, none of the 3 will light-up.

 

[jimbo2k]

Yes they were in series. Never seen that before. 3 automotive wedge bnulbs and we are fine

 

[Andyman]

Let's raise the dead to see if anyone else has my problem. My lighting circuit seems to be haunted as it works and then doesn't work. The right side lamp has been my focus for reasons unknown as the lights lit when I fidgeted with it, but wouldn't when I replaced the cover on the tuner. I though the case may be impinging on the lamp and so I massaged the lamp and it would randomly light the circuit. Jumpering a replacement in parellel usually lit both lamps weakly and today I cut one wire and clipped the it in and it worked. But I attached the new bulb into the circuit in place of the old one and it failed again. I then connected the two leads and that failed also. Very frustrating.

All the wires are pretty much static so IDK how they could be flexing and opening the circuit at a break. I'm considering pulling the base to look at the two leads that feed the ends of the circuit. I've taken readings on the dark circuit and oddly enough they are low mv readings and not a full 8V.

Any ideas on where I should look next??