I got the TS520S it works on Top Band but is restricted to 10 watts. If you
try to turn up the juice more than that,
it might burn the ceramic base, wire wound choke,
that sits in between the 2 B6146 valves
(well it did on mine) I tuned it for top band, wanged up the audio, and a
puff of smoke came out of the finals box.
I read the book, rewound the choke, and asked a few questions. I was advised
that the set was governed some how on top band, as there was a power
restriction on part of the band when the set was built. (Still is on parts)
Mine tunes up a treat on all other frequencies,
its just restricted on 160.