Sony bulb question...

[packrat]

Real simple question....
I'm replacing the little 'Stereo' and 'Dolby' lamps in a Sony 3950 tuner for a friend of mine. I measured the voltage going to the lamps (both are dead) and they are both at 15.4V DC. To me 16V seems a bit high, as I'm used to seeing the little indicator bulbs getting 6V or 8V with Pioneer or maybe 12V to 14V with Yamaha stuff. So, I searched the forums and the same era Sony receivers look to use 8V bulbs, and that's what I remember from an STR-6800 I relamped once.

The 15.4V voltage was measured with no load - will the voltage drop to 12V or 14V when working lamps are installed and drawing a load? Should it be 8V, and something else is wrong?
Any ideas?

thanks

 

[whsh93a]

That's is probably normal - it may only drop to around 5V when "off", too. For example, I found out recently that some of the Sony STR units use that higher voltage as well.

DH

 

[rpampt]

I may be the one of which whsh93a speaks of. I just changed the bulb in my stereo indicator on a Sony STR 6055. It read 15.5 when in stereo and 5.5 when in mono (off). If you need new lights, whsh93a is the man to see.

I've gotten more than one set of LED's from him and they are nice and reasonable.

 

[packrat]

for future reference..
I tried a 12V 35mA bulb and got 5V across it and a dim light. I then tried a 6V 35mA bulb and it lit up nicely and results in 5.5VDC across the bulb and 33 mA current draw. Both the stereo and Dolby bulb are the same.