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Hick 209A VTVM
#16

Found R41 was leaking as well. Read 10K static once power was on bleed to 7k. This 209A Unit had battery and rust all over. I will replace it as well.
#17

Thx Mr Mondial no longer is the dial slamming to either side hard. It does tap. The 3 diodes has worked for that. Im thinking of adding another 25v 100uf into the circuit. Because when using ohms to zero it taps. Also when I release from zero. Ohms is working with in 10%. DC is off by 4v. I was measuring direct. No 3.3M resistor. Before I continue with cal. Im putting it all together, replacing last var resistor. What it seems like is the battery acid is still inside the resistors. I will take them apart later.
#18

No AC probe prevents calibration. DC calibrated up to 500vdc. The cap and inductance not working right. Zeros but meter goes half way.  Here are the v2 v3 pins. It might be how the 6.3vac is hooked up to the probe. R9 does receive 6.3 vac. I will check on the 6.3 Vac path. Have not checked the total path.
Tube          1       2      3      4      5        6        7          8
V3 6SJ7    0       0     8.3  .26   8.3  105.5    0      105.5
V2 6X5      0       0     2.93  0   .034  -1.794  0          0
#19

Brad, are you talking about the 3v power supply not having enough current? Did you use a LM317 regulator? Just curious. I also didn't note any kind of heatsink on the regulator. Does or did it run cool enough?

If I could find the place called "Somewhere", I could find "Anything" Icon_confused

Tim

Jesus cried out and said, "Whoever believes in me , believes not in me but in him who sent me" John 12:44
#20

(12-19-2016, 07:05 PM)Bradley Rush Wrote:  Yes it was here is its schematic. With the other issues my VTVM was having  I have not returned to the lm317 power supply. I was trying to find a data sheet or a 1.5vdc to see its max current pull.  The slamming of the meter was do to the heating up of the balancing circuit.


Attached Files Image(s)
   
#21

Here is the same for 1.5 vdc


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#22

Thanks for posting those schematics. I am going to build a 1.5v power supply to replace the battery in a Heath I restored. I was going to use the LM 317T regulator, run it off the filament. I restored a tube tester that liked to bang the meter, put a 1500mfd cap across it and solved the problem.

If I could find the place called "Somewhere", I could find "Anything" Icon_confused

Tim

Jesus cried out and said, "Whoever believes in me , believes not in me but in him who sent me" John 12:44




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