Designs we love to hate!

[Username1]

EM -I don't know what you mean by helper magnets.
They are the static convergence magnets....

Sorry I didn't see that the normal turn adjustments at the ends of the coils
were not there..... I guess they saved a lot.......

Old_Coot - I guess they thought no one would ever need to work on those sets....

.

[walterbeers]

Sony color trinitron sets made in the 80s that used the SG613 switching triac (or what ever the device was called). One little problem, like a bad connection in the horizontal or in the power supply, or a bad cap, etc, and poof, both of them would short out. Spend a bunch of money on new ones, solder them in, and thinking you've got all the problems taken care of, and then you plug it in and again, poof, another $40 or more bucks down the drain. And besides that, only the exact original Sony SG613s would work. Some other manufacturers (including ECG) made copies of them, and if they worked at all, they only lasted for at the most a month or two. Most TV repair guys tried to avoid those sets like the plague. I had one here that was working beautiful, and then it lost the picture due to an open transformer providing filament voltage to the CRT. Disconnected the leads to the filament and supplied filament voltage from an external supply, and had a great picture. Tilted the boards back into place, and a connection or something either shorted or broke loose, and yes, poof, the SG613s were history. Never the less the set got junked out.

[Zenith26kc20]

The rotary VHF tuners that used conductive paint (like the stuff used on remote buttons) instead of metal contacts. The local tuner rebuilder hated working on them. He would bend the contact fingers to a spot that wasn't worn. And all of the contact area was covered by a white round piece of plastic, forcing the rebuilder to disassemble the entire horror!
Ball Grid Array ICs! JUNK!

[Findm-Keepm]

Originally Posted by Zenith26kc20

The rotary VHF tuners that used conductive paint (like the stuff used on remote buttons) instead of metal contacts. The local tuner rebuilder hated working on them. He would bend the contact fingers to a spot that wasn't worn. And all of the contact area was covered by a white round piece of plastic, forcing the rebuilder to disassemble the entire horror!
Ball Grid Array ICs! JUNK!

Ugh, how I hated those tuners! Printed tuner stator contacts, and limited life. Korean sets had them, and we saved every Japanese tuner to replace them - the little Sanyo and Hitachi BW sets had tuners that were solid. PTS had a universal DIN tuner that would work, but it was 24 bucks - too much to use a replacement.

[Findm-Keepm]

Originally Posted by walterbeers

Sony color trinitron sets made in the 80s that used the SG613 switching triac

Um, they stopped using SG-613 and SG-264 Silicon Controlled Switches in 1978. After that, conventional transistor deflection with 2SC1116s and those funky TX-series transistors...

We had very little trouble with them - the trick was to replace the (leaky) SID30-15 (GH3F) diodes, and check all the sub-10K carbon resistors in the gate circuit for opens. You also had to check for a presence of the drive signal to the gate - some CX-numbered chip provided it, and without it, you'd eat the SG-613, as the SG-613 would be on all the time. Most of the sets we saw were lightning strike sets.

We bought SG-613's direct from Sony National parts, as they had improved the SG-613 to the SG613-A (marked with an A below the SG613). The ECG276 replacements were remarked non-improved SG-613s, and would fail with certainty.