Rogers Model 7R622 1935 Tube Radio Video #4 - Signal Tracing

Before starting to replace components, I'd like to know more about the operation of the radio so I've decided to trace a signal from the antenna through the radio to see where it stops.

[@willthecat3861]

Radiotron was RCA... or RCA Radiotron. Cunningham refers to Elmer Cunningham's company. Elmer Cunningham was an early American pirate radio tube manufacturer whose company was bought out by RCA. He ran RCA Radiotron.

[@tomhague1162]

You noted a burned multi-turn coil in an earlier video. If good, should it not have shown at least some resistance?. I believe you measured "0" ohms which should indicate a short in the broadcast circuit which could cause the lack of response from the signal generator. Could we examine this coil further? This was the primary coil, i believe.

[@asmallmatter4441]

IIRC he got 0,1 Ohms on the 200 Ohms range when testing across the primary of the antenna coil. This seems low indeed. Going by visual inspection alone based on the close- ups in the previous to last video the coil looked highly suspicious.
His chinese component tester should be able to read the inductance on that coil. And setting the band switch to SW would isolate the BC band antenna coil from the circuitry to where no desoldering is needed. It would be a 30 second test. But like so often with him, crucial observations slip past him, get misinterpreted or are simply ignored, leading to video after video of him chasing his own tail.

[@jimburns348]

Your cats are using your shirt drawers for a bed.

[@TheGalaxyhopper]

It’s a hard fix

[@larrygorvin7561]

To many switches and meters Jim.

[@fiercefeline5096]

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