In order to minimise returns, they specify this minimalist TRF radio needs a "20-ft aerial wire". One might also be tempted to earth the chassis as well for more signal but they warn against it

Most sets here were designed for a 25ft antenna and there is an old RCA chart, that shows the performance at different lengths, related to frequency. I have a copy, which I am pretty sure is in "Rider" & on the WEB. Main long wire antenna here, is around 34metres.

The earth return on many of those sets was the "Line Cap": That in reality is why its where it is. With those sets if there is an external antenna its also got a 0.01mfd Line Cap in series with it, to stop people getting zapped. The line cap to Neutral really defeats the need for another grounding, when it is in its proper place: Chassis to neutral or Common rail to Neutral in this case. It is actually the RF pass cap, not a filter.

Some argue that in big inner city buildings, connecting to the common earth / ground introduces noise. There is the odd set where the antenna coil primary is isolated.

With RCD's the Neutral floats after it and is an entity, as is then, not tied to the earth / ground (safety wire).

From before the data sheet says TRF. That still means it needs an alignment to ensure all tuned circuits are on the same frequency.

Marc

On closer inspection of this little set last night I have summised that it can indeed be repaired. I am going to spend sometime just fixing the antenna coil ( litz wire) , the tuning mechanism ( missing pulley) and the speaker which are all possible. Then while waiting for the valves to arrive I will slowly recap and clean it up. It may just be a shelf queen ( I hate them ) but I can see some fun and a few cuss words LOL. From what I have seen it is a cheap set but a well designed one at that.
Having said that I have worked out the tuning mechanism! All I need is a bicycle spoke and a pulley which I have both of.

Might be worth checking the speaker transformer for continuity before spending a lot on parts.
I'll bet that tin case gets mighty hot when running.

Irext I'm not too concerned about the speaker transformer! I already have a replacement.

Crack a 9V battery across the primary of the speaker transformer. That tests both; Unless you here the sound of silence. Or its missing?

Marcc I did crack a battery across the primary of the speaker transformer and low and behold the toasted looking speaker sent out a healthy crackle.

Looks often deceive it may need the cone, patching, cleaning, or spraying with a binder, however: Its not broke don't fix it! Repair the rest of the set first.

Marc

I have worked out how to repair the tuning mechanism ( a piece of old bike spoke and a pulley) but the coil wire maybe hit and miss. It's on the iron core tuning ( no tuning gang ) RF side.