torstai 8. toukokuuta 2014

TV antenna amplifier (another one)

I had this old antenna amplifier ready to be thrown out, but just out of curiosity I decided to open it and see what's inside. Our house was built in early 90s, and according to our neighbors the family that originally lived there was quite religious, in this context meaning that they did not have TV. The area has cable TV but it was never connected to this house. At least the inside wiring was done so connecting TV should be easy later.

Next family living there was ... well, cheap. I've been finding their half-assed fixes (and I'm using the word very liberally here) since moving in, fixing them properly one by one. Even the TV setup was cheap; apparently they bought old antenna, with associated electronics from one neighbor that was updating their system. So this amplifier is likely from the 80s.

Outside there's on/off switch, gain control, indicator LED, one input and two outputs, so quite usual configuration there. The plastic has gotten quite brown and slightly broken from some places.

Assuming that it has usual clips holding it together I tried to pry it open. Whoops. And I didn't even have to use a lots of force.

Right, here's the screw, under the sticker. Finding it first wouldn't have helped anyway, plastic was so badly deteriorated that it would have broken anyway, just from different place.

And the PCB. Top left is on/off switch, below it a fuse (whopping 500mA! Why exactly has someone decided that this thing is allowed to consume 100W is beyond me. Damn thing seems now more like a house fire waiting to happen. Of course I have no way of knowing if the fuse is original or one of those half-assed fixes mentioned earlier), then transformer, on right of it diode bridge and smoothing capacitor. Two round black things with text on them are RF transistors (types BFR 90 and BFR 91A), rest miscellaneous resistors, capacitors and inductors. Nothing too special here.

 So there. Now this thing goes back to trash bin. For good.


1 kommentti:

  1. I had this old antenna amplifier ready to be thrown out, but just out of curiosity I decided to open it and see what's inside. Our house was built in ... atnamplifier.blogspot.com

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