The AM Forum

Hello to all,
Does anybody knows the value in mA, for the Kenwood TL 922 plate meter?

  Does the meter have any markings on it to indicate what the full sale current is? Some meters have a "FS=xxx" value in very small print somewhere on the meter face, possibly obscured by the bezel so you'd have to look closely. I'm assuming your question arises because the meter is no longer functional, so you can't disconnect it from the circuit and use an adjustable power supply to find out what the full scale value is?
   Looking at a schematic, there's a 1.5K resistor in series with the meter; both in parallel with a single 1 ohm resistor. The meter's face is calibrated to indicate 1 amp full scale, and neglecting any internal resistance in the meter, 1 amp would give - assuming I did my math right - 666 micro-amps through the meter at full scale. This assumes no internal shunt or series resistor in the meter.

Hi, thanks for your answer, well no , the meter don´t have any FS print value  unfortunately.  Yes the meter is burn because a little  mouse go into the tube compartment trough the fan, and after an outstanding fire cracker show, the meter , the  and 2 resistors blows away.   My idea is, before I dismantling the amplifier in order to get access to the meter, see if on my Junk box I have any similar meter value, and try to fix the new mechanism inside the original meter body, or just wait until I found a replacement

Best Regards
Pedro XE1YZY

Hope it all works out for you. Unless you insist on having a meter that looks like the original, you've got plenty of options; all you need to do is find a suitable meter that physically fits in the front panel.  By crunching a few numbers and choosing the right shunt/series resistors, you can make almost any DC milli-amp/micro-amp panel meter work. Check out some of the inexpensive Chinese panel meters available on Amazon or eBay - you can probably even find a 0-1 amp DC panel meter and thereby skip the resistors altogether.  Good luck.