Home Theater Forum and Systems banner
1 - 4 of 4 Posts

·
Registered
Joined
·
16 Posts
Discussion Starter · #1 ·
I know, they are almost 50 years old, but hey... I am sentimental with these headphones.

I am trying to repair these headphones that have dual tweeters and dual woofers built in and the controls for both volume and tone for each side. Not only that, they are made of metal and leather! Yes, real leather! That is why so many are still out there that look great but don't work. The main issue is the variable resistor or potentiometer that was used back in the 70's. It is prone to bulid up on the coil which leads to scratchy sounds and poor performance. I also have a blown woofer, but thats another problem.

I cannot find the potentiometer anywhere and was wondering if anyone might know where I would find a new replacement for them. Looking up the part number did not help (again, 50 years old) and the web sites that might have something about the headset is skim. These are dual, separate potentiometers that have a shaft for the volume and a separate shaft for the tone.

Poteniomter:
Violet brand - wire wound, model B-0.8W (0.8 watt)

Info
8Ω impedance
1.75" poly woofers
1.25 poly tweeters
Response 20HZ to 20KHZ (no +/- provided)
SPL 108 db/0.3V
Max input 500mw

Any help would be appreciated. Even you say junk them, it would not be beyond what I have been thinking.

Thanks!
 

Attachments

·
Registered
Joined
·
1 Posts
I know, they are almost 50 years old, but hey... I am sentimental with these headphones.

I am trying to repair these headphones that have dual tweeters and dual woofers built in and the controls for both volume and tone for each side. Not only that, they are made of metal and leather! Yes, real leather! That is why so many are still out there that look great but don't work. The main issue is the variable resistor or potentiometer that was used back in the 70's. It is prone to bulid up on the coil which leads to scratchy sounds and poor performance. I also have a blown woofer, but thats another problem.

I cannot find the potentiometer anywhere and was wondering if anyone might know where I would find a new replacement for them. Looking up the part number did not help (again, 50 years old) and the web sites that might have something about the headset is skim. These are dual, separate potentiometers that have a shaft for the volume and a separate shaft for the tone.

Poteniomter:
Violet brand - wire wound, model B-0.8W (0.8 watt)

Info
8Ω impedance
1.75" poly woofers
1.25 poly tweeters
Response 20HZ to 20KHZ (no +/- provided)
SPL 108 db/0.3V
Max input 500mw

Any help would be appreciated. Even you say junk them, it would not be beyond what I have been thinking.

Thanks!
i tried in vain to include a schematic but ran out of patience. You can search for “potentiometer schematic”. Using a multimeter, measure the resistance from pin 1 to pin 3 (as long as the pot is disconnected from the circuit, the knob position doesn’t matter). That resistance is typically 10k or 100k ohms, but it may be different. Now, turn the knob all the way to one stop and count how many revolutions it takes to hit the other stop. As example, you may read 10k ohms and turn the knob 10 full rotations, in this case you would look for a 10k, 10-turn potentiometer rated at least 0.8W. Check both the volume and tone devices as they may be different.
 
1 - 4 of 4 Posts
Top