630TS Lost the Vertical

[Electronic M]

Primary to secondary leakage in the blocking trans could cause bias issues...Shorted turns could detune the frequency and suppress oscillation. Did you compare tube/schematic voltages in the vert stage yet?

[old_coot88]

Blocking xfmr was my first thought, once he got sweep by injecting at the osc. grid.

[Crist Rigott]

It was the blocking transformer! I had another one here and put it in. Bingo!
Thanks for all the suggestions.

[old_coot88]

[jr_tech]

Can you measure anything odd on the bad transformer? Seems as if we have seen several now that have appeared to be good, but did not function.

jr

[Crist Rigott]

Originally Posted by jr_tech

Can you measure anything odd on the bad transformer? Seems as if we have seen several now that have appeared to be good, but did not function.

jr

I measured the leads each other and to the case. Everything seemed good. I then hit it with my heat gun and got this:




Yup, a transformer! I ohmed out the windings again and the values crept up from pri-1130 to 1533, sec-153 to 173. I also checked for shorts between the leads and shorts to the core. All seemed good.