Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

Thread Closed
Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Replacing a Field Coil with a PM Speaker - Please Help
#16

Good point on getting 89 Ohms for a VC. There is also Ni Chrome Icon_lol

0.89 Ohm VC resistance on a tube amp has a bad smell also.Icon_crazy

Can someone with a good 84B measure the VC resistance?Icon_redface

Ron probably knows without looking
#17

Once upon a time, eletrolytic capacitors were more expensive than chokes, and coil magnets were better than the "permanent" magnets of their time.

So in fxing up an ld set that doesn't care how how you got there, inexpensive larger value capacitors, resistors if needed, and permanent magnet speakers can be used.
#18

Sparky

why exactly are you going to fry anything? and where is that 11:1 ratio came fom?
Again, the speaker voice coil in 84 is 0.89 Ohm (zero point eight nine), not eighty nine ohm.

And so it is more or less in all old early Philcos: 90, 20, 70, 111, 95 and such.
The transformer they use in 2x71A or 2x45 pushpulls are more or less 100:1 ratio hich will turn 0.89 ohm into 8.9 kOhm impedance that ain't gonn burn anything.

So I m not sure what the post was about, but clearly no one uses 1:11 rAtio an 0.89 ohms there for 42 tube.
#19

My 84b had hum to it was caused by a bad ground on the detector tube it was the rivet on the the tube socket that was used for the ground.
#20

Seems like I remember someone having a bad gnd at the rivet on the #42 socket too.
GL
Terry




Users browsing this thread: 14 Guest(s)
[-]
Recent Posts
What should I offer?
I think you have a chance at purchasing a 48-1286, based on the cabinet hardware. Only 8700 were produced, so it is a r...GarySP — 02:28 PM
What should I offer?
I am not sure what radio it is, but seems like a 1950 AM/FM set. Or from 1948, possibly one similar to 48-1264. In any ...morzh — 12:44 PM
What should I offer?
I have an opportunity to acquire this radio-phono, but the owner wants me to make an offer. Tried searching images, but...nocusr — 12:29 PM
Atwater-Kent 84, restoration.
So, I unwound the coil; it is 700 turns of AWG40 wire. I modeled it on a couple of different calculators and I got about...morzh — 12:29 PM
Atwater-Kent 84, restoration.
Ron From the conversation, it was my impression he was a pretty old dude who is looking to place his radios in good h...morzh — 12:16 PM
Philco 49-1040
Yes, and it's surprisingly common for early TVs to be mostly or all original. My thinking is that they were retired ear...Bob Andersen — 11:59 AM
91H Code 126 Restore
Hi Nick, Usually the dashed lines connected to components means the part is a substitute in the circuit for specific ...RodB — 09:42 AM
462ron
Mike when I got to the guy’s house to pick up the set, he gave me a tour of his home and garage. Wow, his living room co...462ron — 09:10 AM
91H Code 126 Restore
I'm pretty sure that the dotted line I circled in an earlier post signifies that it is applicable to the 226 model which...RealRider — 08:05 AM
Philco 49-1040
Hello bob, that underside looks like it is all original ! Sincerely Richardradiorich — 02:07 AM

[-]
Who's Online
There are currently no members online.

>