MJLorton Solar Power and Electronic Measurement Equipment Forum

Older Technology => Older Technology => Topic started by: SeanB on September 26, 2013, 04:03:14 PM

Title: Poor transistor
Post by: SeanB on September 26, 2013, 04:03:14 PM

Here is an old power board from a Phillips amplifier, with the original transistors still mounted on the heatsink.

(http://farm4.staticflickr.com/3834/9914093025_4a448f3dbf.jpg) (http://www.flickr.com/photos/33277124@N08/9914093025/)
IMG_1281 (http://www.flickr.com/photos/33277124@N08/9914093025/) by SeanB_ZA (http://www.flickr.com/people/33277124@N08/), on Flickr

BDY20, tightened down till it warped like that. Equivalent to a 2N3055.

(http://farm6.staticflickr.com/5506/9914188484_7026bce6d2.jpg) (http://www.flickr.com/photos/33277124@N08/9914188484/)
IMG_1282 (http://www.flickr.com/photos/33277124@N08/9914188484/) by SeanB_ZA (http://www.flickr.com/people/33277124@N08/), on Flickr

Really bent there, but it lasted a long time.

(http://farm3.staticflickr.com/2890/9914150796_f21f53bb57.jpg) (http://www.flickr.com/photos/33277124@N08/9914150796/)
IMG_1284 (http://www.flickr.com/photos/33277124@N08/9914150796/) by SeanB_ZA (http://www.flickr.com/people/33277124@N08/), on Flickr

Top was easy to remove, and the inside shows the hermetic seal was broken, but the die still worked.

(http://farm4.staticflickr.com/3672/9914307683_25982acc06.jpg) (http://www.flickr.com/photos/33277124@N08/9914307683/)
IMG_1287 (http://www.flickr.com/photos/33277124@N08/9914307683/) by SeanB_ZA (http://www.flickr.com/people/33277124@N08/), on Flickr

Even the soldered tabs corroded, but it was working until I stripped it for scrap. Phillips really do some odd designs. This one had linear sliders for all controls, but instead of using a linear slider the designers used a regular rotary pot, and placed a spiral 4 sided extension on the pot, with the slider having a operating arm that rotated the pot as the slider was moved up or down.

Title: Re: Poor transistor
Post by: SeanB on November 30, 2013, 07:27:56 AM

Another transistor die, this was a high power device in a bolt down package that unfortunately died.

Title: Re: Poor transistor
Post by: TVman on June 04, 2014, 12:08:57 AM

Wow!(http://www.eevblog.com/forum/Smileys/default/icon_smile_thumbsup.gif)