[Milsurplus] LM practical use

[Bill Cromwell]

Hi Howard,

I have the original books with my LMs but I built tuning charts for my 
RAK that could also be made for an LM or BC-221. I entered a number of 
cal points into a spread sheet (one for each band) and then made an X-Y 
chart with a nice curve showing dial reading vs frequency. It can be 
used to find the dial setting for a desired frequency or to determine 
the frequency of a found, on-air signal. There is always a way:)

73,

Bill  KU8H

bark less - wag more

On 6/10/20 2:42 PM, howard holden wrote:
> I bought an LM-18 with a book at a hamfest, then swapped it with the NJ 
> Naval Museum (USS Ling SS-297) so they’d have one WITH a book. I then 
> took the one without a book, and made my own cal chart for all freqs in 
> one Kc steps from 3500 to 3600 – I don’t do AM but the same idea would 
> apply – in which I kept the corrector control at mid-point. I recorded 
> the interpolation scale readings for each one KC step. For mine I got 
> 3480.0 to 3687.4. Each one Kc step required a 2.0 or 2.1 step on the 
> interpolation scale. This very small change in step to step enables me 
> to easily interpolate readings down to about 50 cycles with pretty good 
> accuracy. And having the interpolation scaler readings enables me to 
> accurately calibrate the meter with the internal crystal.
> 
> 73, Howie WB2AWQ