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I have a 1936 era Weber amplifier (6049A.)

Can anyone help me identify the 2 components I have circled in black?

Red/Purple and Orange/Black (one of the other components also has a green circle on it.)

Also, a lot of wires are cut, does anyone happen to know where I can get a schematic for this amp (2 56, 2 2A3, and 1 5Z3 tube)

Image with 2 unknown components circled

I have measured some of the caps, I got:

Major Clr ! Minor ! Dot   ! Measured
----------+-------+-------+-------------
Red   |Violet | n/a   | 3.19k, 3.01K
Orange    |Black  | n/a   | 35,2K, 42K 
Brown     |Black  | green | 1.02M

Is it right to assume that if there is not a dot on the long (most) color of the resistor that the multiplier is the same color as that long (most) color?

I have started to construct a schematic: enter image description here

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    \$\begingroup\$ resistors I think, but mainly because I can't see any other resistors. if they have sposts that are facing away from the camera definately resistors. \$\endgroup\$ – Jasen Apr 23 '19 at 3:33
  • \$\begingroup\$ Disconnect one end and measure... \$\endgroup\$ – Solar Mike Apr 23 '19 at 3:54
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Those are very old resistors. The two color bands and the color of the dot determine the value. At the moment I can't find a good link which way to read the resistance from the color bands and dot but the color coding itself should be same as today.

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Some OLD resistors have BED Body---End---DOT for the color-coding.

The 1MegOhm from grid to ground seems appropriate for grid biasing, given the expected Igrid is ~~ zero. Paper capacitors to the grid will bring in the AC signal.

The 3Kohm between cathode and ground seems appropriate; 1mA produces 1 volt drop, making the cathode become 1 volt above that (grounded) grid. What is the cutoff bias for the "56" tube?

And the 30Kohm in the plates have gotten HOT and increased in value over the decades.

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"Body, tip, and spot".

I can't see the spots, which would usually be on the end (or cap) opposite the tip. But it appears those two resistors are 27x (2700,27k,270k) and 30x(3k,30k etc).

Which suggests they might be 27k and 30k in the anodes of a phase splitter?

Use a multimeter, bearing in mind they may easily have doubled in resistance from heat and age. It should at least establish which decade they are, if you can't find the spots!

(The brown waxed paper roll underneath will be a capacitor)

Seeing the updated information : yes, if the spot is invisible, it is either the same colour as the body, or fell off long ago. Your measurements are consistent with this :

  • Red/Purple/Red = 2.7k, so these have only drifted little more than 10%, and don't need replacement
  • Orange/Black/Orange, 30K. Resistors in this range are often anode loads, as your schematic shows, and run hot. So it's typical for them to increase quite a lot (35 or 42k are well within expectations, and still usable, but worth replacing if you want original performance.
  • Bromn/black/green = 1 Meg. These tended to be lightly loaded, e.g. a grid leak taking only microamps, and sure enough its value is still spot on.
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probably an inductor? which is a major part on an amplifier's output circuit.

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