[ARC5] My newest LM...

[Roy Morgan]

On Dec 4, 2009, at 7:31 PM, jcoward5452 at aol.com wrote:

>
> ...is also my eldest. I just received a LM-2,... 1937.

Jay,

Long live the LM!  That is the oldest LM I've heard of as best I can  
remember.

Two days ago I retrieved a BC-221 AH  from the barn and started  
working on it.  It's in the wood case and has a nicely done power  
supply in the battery compartment.  It gives lots of  hum just now..  
supply filter caps most likely.  And the function switch is seriously  
stuck at the switch mounting bushing.  Frozen solid.  I may have to  
apply penetrating fluid and wait for some days, but if that fails,  
I"ll have to do surgery.  This unit is worth it  because it is  
execptionally clean.

I also have at hand two LM generators, one with book one without. No  
supplies with these two (though I do have other LM's with supply).   
Very few cords.  Very few mounting plates.

I have an LM-13 carrying case - metal, wrinkle finish with fittings  
for the canvas cover, I think.  The front spare tube compartment cover  
is missing, alas.  It appears that the LM bolted in the top  
compartment on the centers of the shock mounts found on the normal  
mounting bases.  I assume that there were shock mounts used there, but  
the normal mounting base will not fit into the case under the LM.

Years ago, Bob Keys wrote a program to generate a "new calibration  
book" for the LM and BC-221.  I have a copy here of the program, but  
have not gotten it to run.  This would be most useful for units with  
no calibration book.  If you or anyone else would like to give it a  
try, let me know.  I think  it's written in Basic, and the source code  
is there.


> ...I've opened both units and they are very clean and complete with  
> all tubes in place.At first I thought the crystal was missing,only  
> to find it stuck to the case by what was once the rubber cushioning  
> pad.

We have learned that the crystal for the LM and BC-221 are not the  
same and do not interchange.  A jumper or two on the socket might let  
them interchange, though.

Roy

Roy Morgan
k1lky at earthlink.net
529 Cobb St.
Groton NY, 13073
Home: 607-898-3607
Cell: 301-928-7794