Sansui 771 lamp temperature

[MDN_Odense]

I just got a Sansui 771 from german eBay, excellent and untouched condition, all components original - even the fuse lamps are the original 7 volt.

Nice and wide sound, bias and DC offset easily adjusted. No hum problems. No heat from electronics - but 38-40 degrees celsius inside the fuse lamp housing, spreading to the top of the cabinet. My wife says there's a bit of smell too. Checked voltage: the fuse lamps are getting 6,22 volt AC which should be ok.

Should I bother? Is it a problem seen before?

(I also have a 661 with too much hum at volume zero. It was really cheap (500 kr = 65 euro). I tried all possible cleaning and recapped the filter caps. Still humming. Shelved until later.)

 

[Robisme]

They do get very warm. Are you sure they are original and that nobody replaced them with the wrong ma rating?

Probably OK, but if it bothers you, you could install LED fuse lamps.

Rob

 

[Hyperion]

I tried all possible cleaning and recapped the filter caps. Still humming. Shelved until later.)

Common problem with the xx1 series, various internal ground connections seem to need checking and cleaning.

 

[MDN_Odense]

Lamps were 7V 0,3A like the original ones according to service manual.

However I changed to 8V 0,25A and painted the lamp housing bright white inside to compensate - it looks great when power is on and the heat has decreased.