RCA TRK-120, without its TV chassis

[tubesrule]

Steve,
Check out the TRK12/120/9/90 schematics in the Red Books. If you look at the power supply sections you'll see they have the main filter cap values (and a few other parts), in both the LV and HV sections, shown with a second value in parenthesis for 50cycle operation. For instance the HV caps are shown .03uF (.1uF 50 cycle) This is also the same on the TRK5/TT5 schematics. I have never seen a set that was actually setup this way, but perhaps this was for the LA market.

There is a section in the manual on the differences between the 50/60 sets. It mostly outlines the capacitor value changes, the transformer changes, the the LV rectifier changing to a 5T4. One very interesting aspect is these sets still ran on 60Hz video so the wobble in the picture when running them on 50Hz mains must have been a problem. They used a metal crt sleeve instead of the cardboard one and a double wall metal sleeve over the yoke. Still I imagine wobble would have been a problem.

Darryl

[Steve McVoy]

Thanks Darryl. I learn something new every day.

[ChrisW6ATV]

Steve-

Here is a picture of the label. Thank you for the paint information.

Dieseljeep-

Thank you for the note about 50 Hz power in Los Angeles. That is likely where this set came from. The differences appear to have only been in the TV chassis; the radio main and power supply chassis are the same in both versions of the TRK-120.

Darryl-

Those are interesting comments about the 50 Hz wobble issue.

My set's tube chart has the TRK-120 layout but uses the older tube numbers (1852,1853) rather than 6AB7 and 6AC7.

[rld-tv01]

I was wondering if the TT-5 I purchased recently in Long Beach CA could has been produced for the Los Angeles market but it appears to be 60 Hz by the label. So it most likely was brought in later by someone moving into the area.

[Tom Albrecht]

I had no idea that Southern California was on 50 Hz power at one point. Just did some reading up on it, and indeed it was -- until 1948. It was a sizeable market, so manufacturers made special versions of all kinds of products specifically for Southern California. Amazing!

Japan today is still cut in half -- 50 Hz in one half, and 60 Hz in the other. When the electric trains cross the boundary, they coast without power a short distance and pick up the new frequency after a few seconds. They should have made the switch like Southern California did long ago.