Ok. Let’s try this again…RCA 9TC240 Alignment

[Penthode]

There are no secondaries. What you are calling the secondaries are the traps. The stages are capacitively coupled not transformer coupled except for the link between the mixer and 1st Video IF stage.

You are shunting each of the coils.

Do you understand why you are shunting the coils with the resistors?

[Chris K]

Originally Posted by Penthode

There are no secondaries. What you are calling the secondaries are the traps. The stages are capacitively coupled not transformer coupled except for the link between the mixer and 1st Video IF stage.

You are shunting each of the coils.

Do you understand why you are shunting the coils with the resistors?

No you have lost me. I guess transformer is the wrong term. I don't know what "capacitively coupled" means. I think the purpose of the traps was discussed before and at one point I had the concept but now I'm not sure. I think I remember they were to "trap" and eliminate certain frequencies from the video signal minimizing interference but the only one I recall being discussed was T-103 and the 21.25MHz trap.
There are a lot of terms I listen to without completely understanding them. I know the standard definition in everyday life of the word "coupled" but in electronics I'm not so sure. Most of what has been talked about leads me to think when 2 things are "coupled", one affects the other despite not being directly connected. Is this correct? Capacitively coupled??? Nope. Loosely coupled??? Nope

[Chris K]

Originally Posted by Penthode

There are no secondaries. What you are calling the secondaries are the traps. The stages are capacitively coupled not transformer coupled except for the link between the mixer and 1st Video IF stage.

You are shunting each of the coils.

Do you understand why you are shunting the coils with the resistors?

When the instructions say "shunt the primaries" I just assumed there were secondaries

[Penthode]

Originally Posted by Chris K

When the instructions say "shunt the primaries" I just assumed there were secondaries

Funny. I went back and looked at the instructions and it calls the units transformers and calls the coils "prim." implying primary. Semantics.

The main issue is the coils are stagger tuned to cumulatively provide the wide bandwidth required. The shunting of the coils with the 330 ohm resistors is to effectively remove each tuned IF stage so that the response will be governed only by the tuner to 1st IF over coupled transformer link.

[Chris K]

Originally Posted by Penthode

Funny. I went back and looked at the instructions and it calls the units transformers and calls the coils "prim." implying primary. Semantics.

The main issue is the coils are stagger tuned to cumulatively provide the wide bandwidth required. The shunting of the coils with the 330 ohm resistors is to effectively remove each tuned IF stage so that the response will be governed only by the tuner to 1st IF over coupled transformer link.

In the schematic, what do the twin up and twin down arrow designations next to the coils mean?

[Yamamaya42]

Originally Posted by Chris K

In the schematic, what do the twin up and twin down arrow designations next to the coils mean?

I assume that's to denote an adjustable core type coil on the schematic.