10-29-2016, 10:43 PM
(10-29-2016, 08:35 PM)TerryMSU Wrote: Ron, my personal inclination would have been to stick with a field coil design as you suggested for the exact reasons you suggest. Terry, the magnetic field is proportional to the product of turn count and . Double the turn count and you can use half the current. In any case, I am very appreciative of the input all three of you folks have provided. While I have the engineering knowledge and experience to know what might be possible, I am lacking in the practical wisdom that you all have provided. If the cabinet I am considering pans out and my current chassis is functional, I will definitely be looking for more advice. The idea of other Philco speakers in a similar size had not crossed my mind.
The cabinet (if I take it) will be coming from Alabama to Michigan. Any recommendations on how to ship it safely and cheaply?
Thanks so much,
TerryMSU
> Double the turn count and you can use half the current.
This is true but you end up with a coil that is physically larger in less you shrink the size of the wire.
In terms of using and resistor I was thinking of cost also (it's cheap like me). A choke (or field coil) is much more efficient in reducing ac hum in comparison to a resistor. If the resistor was the same size FC I would think that the heat generated would be about to same as weather you are use either, both are dissipating the same amount of energy.
You can use a separate choke mounted on the basket of a pm spkr, mounted like the opt. Something like 5H @ 70ma should do the trick. You could go higher in inductance but size maybe an issue.
If you want to have a set that looks original by all means go with a Philco spkr but I'm thinking it may be a bit harder to find and may need reconing.
Just wanted to throw out the most options.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry