[NJARC] Capacitors

[StephenTetorka at cs.com]

Hi Guys:

I'm in the process of bringing my circa 1937-39 National NC 81X back to life.
They did a really smart job painting the chassis...it looks like new with none of the usual pitting etc to be seen.

The bugger has a cast metal oscillator coil tray? - about the size of cigar box under the chassis - that slides the whole width on two 1/2" round tracks...powered by a small chain from the panel control.

One capacitor lead is undone.
Might as well change the group.

My fundamental question is:  given a value of say, 0.1 mfd @ 200v...why can't I use any TYPE of capacitor of this value?..even an electrolytic 
( if I knew my + from my - ).

Why isn't a rose a rose?

PS: need an output xmfr for the 25L6..2,000 ohms primary...4 watts.

And those guys put around 200vdc between their ears with the headphones!
I may attempt that tonight with mine since I don't have the speaker.

Thanks,
Steve