[ARC5] Changing LM Freq. Meter filament to 6 volts instead of 12/24

[WA5CAB at cs.com]

The most likely thing is that the hacker simply cut the necessary wires and 
wired the heaters of the three tubes in parallel.  Depending upon how 
intelligent he was the resistor was probably left floating.

There were never any LM models built to operate from 6-7 volt heater supply.  
LM through LM-6 except LM-4a were wired for 12-14 volts.  The remainder 
through LM-21 were all wired for 12-14 and 24-28.  LM and LM-1 operated from a B+ 
supply of 200-260 VDC.  LM-2 through LM-21 operated from a B+ supply of 200-475 
VDC.  Only about 1/3 of all LM models had AC supplies built.  The balance 
operated either from dry batteries or were for aircraft use and operated off of 
B+ supplied from one of the radios aboard.  However, any LM rectifier supply 
ever built will operate any LM oscillator ever built.

In a message dated 4/16/2008 8:59:54 PM Central Daylight Time, 
k1lky at earthlink.net writes: 
> My quick conclusion is that your meter has either been rewired for  
> 6.3 volts and 12.6 volts, or it was built the way you have found them.
> 
> What's the series number of the one you have (and others you have  
> found for 6.3 volts)?

Robert Downs - Houston
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MVPA 9480
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