I wouldn't necessarily call it a 'lab scope' but I think I once saw an large-screen (about 17" diagonal) 'scope used for lecture demonstrations that was magnetically deflected. I think the bandwidth was pretty much limited to audio frequencies. I can't rememebr the manufactuter, maybe Airmec? Waht limits the bandwidth of electromagnetic deflection is often the fact that you have to change the current through the defleciton coils quickly, and this leads to large back EMFs that you driving amplifier has to be able to cope with (suppressing them e.g. with clamp diodes or zeners does you no good at all, it just slows down the response time and thus kills the bandwidth). Of course there have been magneticlaly-deflected XY displays used on vector grahpics systems (the DEC VR14 being an obvious example), but the defleciton rates were not that high. -tony