these are "pyramid" brand, made in usa caps.
i was a bit worried about unsoldering/resoldering them as the leads are quite short, and i read about beeswax caps being vulnerable to heat.
i realise that i can always replace these with the "jupiter" beeswax caps, but i am trying (who isnt) to do this on a budget.
worst case scenario: i wreck the caps by trying to test them. what type should i replace them with?
paper in oil
beeswax
solen
i was a bit worried about unsoldering/resoldering them as the leads are quite short, and i read about beeswax caps being vulnerable to heat.
i realise that i can always replace these with the "jupiter" beeswax caps, but i am trying (who isnt) to do this on a budget.
worst case scenario: i wreck the caps by trying to test them. what type should i replace them with?
paper in oil
beeswax
solen
Simple way to test:
Hook up a 100 to 500V supply (more volts to test to a higher rating on the cap) and connect the capacitor in series with a 1k current-limiting resistor (just in case...) and with a neon lamp.
Operation: after the initial turn-on spike which charges the cap (put up a sheet of paper in case the neon lamp blows, large caps may hold more energy than a neon can handle), any leakage will discharge the cap, putting more voltage across the neon. After a while it drops to the firing voltage and the neon fires, charging the capacitor up to the turn-off voltage. A good cap will fire once or twice in a minute, and that includes the first (hookup) pulse. A leaky one will just blink on and on.
To find the exact leakage current, I = C * dV/dt, where I is the leakage, C is capacitance, dV is the difference in voltage (measure on a scope; it varies with the neon, its age, how much light or radiation is around, etc.) and dt is the time period of the oscillation ( = 1/f).
Tim
Hook up a 100 to 500V supply (more volts to test to a higher rating on the cap) and connect the capacitor in series with a 1k current-limiting resistor (just in case...) and with a neon lamp.
Operation: after the initial turn-on spike which charges the cap (put up a sheet of paper in case the neon lamp blows, large caps may hold more energy than a neon can handle), any leakage will discharge the cap, putting more voltage across the neon. After a while it drops to the firing voltage and the neon fires, charging the capacitor up to the turn-off voltage. A good cap will fire once or twice in a minute, and that includes the first (hookup) pulse. A leaky one will just blink on and on.
To find the exact leakage current, I = C * dV/dt, where I is the leakage, C is capacitance, dV is the difference in voltage (measure on a scope; it varies with the neon, its age, how much light or radiation is around, etc.) and dt is the time period of the oscillation ( = 1/f).
Tim
Hi,
Intrinsically, yes.
The major advantages of the Solens used to be that they were about the only ones availble in large values at 200V + voltages.
Unfortunately, the suffer from a QC problem that detoriates the sound considerably.
Not the ultimate cap but they are excellent value for money. The SN range is audibly better but more expensive.
Cheers,
Intrinsically, yes.
The major advantages of the Solens used to be that they were about the only ones availble in large values at 200V + voltages.
Unfortunately, the suffer from a QC problem that detoriates the sound considerably.
Not the ultimate cap but they are excellent value for money. The SN range is audibly better but more expensive.
Cheers,
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.