1963 Zenith 19" b/w (16K27 chassis)

[Adam]

This is the tv that BigDavesTv picked up for me from ElectronicM at the ETF convention. Usually these Zeniths don't need much, but this time there were 3 separate problems with the vertical.

1. The sync wouldn't lock for H or V, this was R58 on the schematic, same exact problem I had on another set with the same chassis a few months ago.

2. Not enough Vert size, turned out to be caused by that K2. I replaced K1 as well even though it was ok.

3. The vertical would increase in size as the set warms up until it gets too much and the vert linearity is way off. This stumped me for a while, I was convinced it was caused by a resistor, after I had eliminated all the possible resistors I even tried swapping in another yoke and vertical output transformer, but the problem turned out to be caused by the tube itself. After I had tested the tube (and also tried swapping in another tube) eliminating it as the cause of my problem #2, I had ignored it as a possible source of this problem. A new 6EA7 fixed it up.

other problems:

1. The brightness control needed to be replaced.

2. The buzz control was dirty.

3. Weak sound was caused by 6BN6 tube not making contact in its socket.

stuff it still needs:

1. The shaft on the volume control is bent, but it works good, so I left it.

2. Missing antenna

3. The channel number won't focus in center of tuning control. I remember reading a post here that these needed a certain bulb, anyone remember what kind it is?

Pics below...