[ARC5] BC-221-D, tool needed to undo knobs

[Roy Morgan]

The knob set screws on my BCC-221 AH accept Bristol 6-flute spline wrench of 0.096" diameter. This is the Xcelite driver number 99-66. 

I cannot verify that the earlier medium-base tube frequency meters used the same set screws, BUT,

The LM-20 here uses the same setscrews in three knobs and the CORRECTOR metal knob set screw accepts Bristol 6-flute spline wrench of 0.050" diameter. This is Xcelite driver 99-66. 

PS:  I have not heard of METRIC Bristol spline wrenches/screws. If they exist(ed), I'd be glad to get any available details. 

Roy sends.

> On Oct 1, 2017, at 5:50 AM, Leslie Smith <vk2bcu at operamail.com> wrote:
> 
> Hello all,
> 
> I wish to remove the F.P. knobs from a BC-221-D.  
> This is an early model with 5 and 7 pin tubes.