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THE AM BULLETIN BOARD => Technical Forum => Topic started by: KF9CM on August 14, 2007, 12:37:50 PM



Title: Meter Manufacture Information
Post by: KF9CM on August 14, 2007, 12:37:50 PM
Hi to all,

I recently acquired a meter which was made in the UK. In the center of the face is crown with the letters K, A, and M surrounding the crown (I've enhanced the letters for placement and clarity). I believe this meter was originally on the WWII 5A British transmitter. It Looks something like this:
            A
       K wWw M
         {     }


Any information on the meter or the manufacturer would be greatly appreciated.



Thank You

Gary Giles, KF9CM


Title: Re: Meter Manufacture Information
Post by: KB2WIG on August 14, 2007, 01:44:04 PM
King AM ?????   .... ..       klc


Title: Re: Meter Manufacture Information
Post by: KF9CM on August 14, 2007, 09:17:45 PM
I apologize guys,

I was waiting for the meter to arrive in the mail and was relying on a bad picture. Well it's here and the A and M are on either side of the crown so I guess that makes it the Air Ministry. Well that's two letters now for the K which is over the crown. I opened the meter and it's a hot-wire ammeter. After pondering the scale on the face which is .1 to .5 amperes the K might stand for Kilo or 100 to 500 Milliamperes and the internal resistance is 0.7 ohms. I am building a replica of the MKIII transmitter (Tinker Box) located in Station X in Bletchley Park. The meter in that set has the same basic case as the one I described. I guess the meter was made under contract to the Air Ministry during World War II and anyone could have made it. Thanks to everyone for their input.

TNX de Gary, KF9CM
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