[Vintage-Radio] Two more HRO questions

[Donald Chester]

>
>Another question for HRO owners:  The previous owner of mine has bypassed 
>the B+ switch on the front panel.  I suspect that he did this because it 
>was arcing or unreliable.  Until I get a replacement, is it safe to change 
>coils without turning the radio off?

>From my experience with the pre-ww2 HRO, I would avoid changing coils with 
the B+ on.  For one, it's hard  to avoid  getting knocked on your bum while 
pulling the coil out.  There is a point in the process that  leaves the 
entire coil unit at high voltage as the coil unit is slid out.  Secondly, it 
causes arcs at the coil contacts, certainly not good for the contacts in the 
receiver or on the coil.

One problem I had with mine was that when changing bands, putting a cold 
coil into the warm receiver resulted in noticeable drift for a few minutes 
after changing coils.  I solved that by storing the most often used spare 
coil on top or the receiver instead in the wooden box.  The unused coil 
stayed pre-heated while not in use.  That cut the drift way down.

73, Don K4KYV