S
Stefan Huebner
Guest
Hi all,
I have some trouble with a Schneider TV17 chassis. I have replaced the
lopt because the set failed with a short hiss and then a crackle. I
had three or four of them, all with the lopt cracked and arcing. With
this one, the crack in the case wasn't that obvious, but there was a
mark of the arcing on the core. The SMPS controller IC TDA16846 also
went dead, so I replaced it too (searching for TV17 info revealed that
the IC often fails with the lopt). The set ran fine after adjusting
screen grid voltage and focus, but the screen became dark after one or
two hours. What I found is that the 2A medium time lag fuse in the
heater supply was open. I had this once when I started a TV17 PCB
without the CRT board on the CRT neck, so the heater voltage dropper
(I wouldn't call it a regulator...) shorted and blew the fuse. In that
case, replacing two diodes, a zener, the BD677 series transistor and
the 2A fuse cured the set.
Does my problem sound familiar to someone here ?
regards
Stefan
I have some trouble with a Schneider TV17 chassis. I have replaced the
lopt because the set failed with a short hiss and then a crackle. I
had three or four of them, all with the lopt cracked and arcing. With
this one, the crack in the case wasn't that obvious, but there was a
mark of the arcing on the core. The SMPS controller IC TDA16846 also
went dead, so I replaced it too (searching for TV17 info revealed that
the IC often fails with the lopt). The set ran fine after adjusting
screen grid voltage and focus, but the screen became dark after one or
two hours. What I found is that the 2A medium time lag fuse in the
heater supply was open. I had this once when I started a TV17 PCB
without the CRT board on the CRT neck, so the heater voltage dropper
(I wouldn't call it a regulator...) shorted and blew the fuse. In that
case, replacing two diodes, a zener, the BD677 series transistor and
the 2A fuse cured the set.
Does my problem sound familiar to someone here ?
regards
Stefan