[Heathkit] DX-35 meter resistance

[Garey Barrell]

Even easier, if you have a good DMM, is to use the ohmmeter function.  
My Fluke only moves a 50 uA meter two minor divisions.

73, Garey - K4OAH
Glen Allen, VA

Drake 2-B, 4-B, C-Line & TR-4/C Service Supplement CDs
<www.k4oah.com>



Glen Zook wrote:
> There is an even easier method.  Take two potentiometers and put the first one in series with the meter and a battery.  Adjust this potentiometer for a full scale reading on the meter.  Then put the other potentiometer in parallel with the meter.  Adjust it for a half scale reading.  Measure the resistance of the parallel potentiometer and that will be the resistance of the meter.
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> Glen, K9STH
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> Website:  http://k9sth.com
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> --- On Thu, 3/5/09, C E <catman351 at yahoo.com> wrote:
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> If you want to determine the meter resistance of the meter, do it the old fashion way!
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> Place the meter in series with a resistor, say around 100 ohms or so.  Place one end of the meter in series with the resistor. The other in line with a low voltage power supply or small battery. Connect the open end of the battery with the resistor and read the current (hopefull you wouldn't have "pegged" the meter but with a small 1.5 volt unit, you shouldn't have done that.  Read the meter reading. Get a meter (vom vtvm dvm) and measure the voltage across the resistor with everything connected still connected. Using the known voltage from the battery and the voltage drop across the resistor, you should know what the voltage drop across the DX-35 meter.  E=IxR, therefore, E/I=R. Voltage drop across the meter divided by the current read should give you your resistance.  Real easy!  
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