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

Philco 18 oscillator coil rewind
#1

Hello all, I have an open secondary winding on my oscillator coil, item #16 in the parts list with a secondary resistance value of 3.4 ohms. I counted 16 turns of original transformer or magnet wire, which is about the size of a human hair. The smallest transformer wire I have is 33 AWG. When I restring the secondary coil with 16 turns as original, I am measuring 1.2 ohms. So, what is more important here, the resistance value (which I think they used as a measuring reference) or the inductive reactance which is how this coil is actually used? I know the number of turns affects the inductance, but I get the wrong value when checked with a vom. Thoughts?? Thanks!!
#2

Inductance trumps the resistance. The resistance is going to be different as your wire size is larger. If you don't have enough turns it won't oscillate at the low end of the band. Coil is used to couple feedback from the cathode to the grid and is not in a resonant circuit.

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
#3

So should I go with my rewound coil with 16 turns measuring 1.2 ohms?? Thanks
#4

Forget ohms. Go for the turns. Also if you don't have the proper wire (often gauge 42) I recommend you buy a spool, with 30-s radios comes handy more often than I'd like to see it.
If the coil is not a part of the resonant tank the turns is the only thing that matter.
If it were, than everything would matter, turns, length of winding, thickness etc.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#5

Thanks for the help gents!!!




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
The list of my radio & TV collection!
Sorry, these are my old videos, so there are no English subtitles yet. RadioSvit — 06:00 AM
The list of my radio & TV collection!
Yes, MrFixr55. I agree with you, this Galicrafters is structurally very similar to the Zenith Transoceanic H500, as well...RadioSvit — 05:58 AM
The list of my radio & TV collection!
Hi Richard. I really like the Hickok, it is very convenient to use. I have another tube tester - the Soviet L1-3. It is ...RadioSvit — 05:27 AM
The list of my radio & TV collection!
Arran. I completely agree with you. I also noticed that the Canadian consoles General Electric, RCA and De Forest Crosle...RadioSvit — 05:11 AM
Electrolytic restuffing/internals
I don’t have a vise so I had to hold it in my hand. Not optimal but covered up by the hvac tape in the end. I have a few...bridkarl — 11:52 PM
Electrolytic restuffing/internals
Bridkarl A question. For a hacksaw the cut looks a little...jagged. Why?morzh — 11:45 PM
The list of my radio & TV collection!
As usual, an interesting post from you, Peter. This seems to be similar to the RCA 3-BX-671 and the Zenith Transoceanic...MrFixr55 — 11:41 PM
The list of my radio & TV collection!
Hello Peter, Thank you for sharing your new video and looks like your weather is nice their too. it was like 25 Cel...radiorich — 11:05 PM
Electrolytic restuffing/internals
hello bridkarl, I will post some better photos ! Sincerely Richardradiorich — 10:14 PM
Electrolytic restuffing/internals
I just taped the two pieces of the cap together, but I can see your method is better. I just held the lead in with solde...bridkarl — 08:18 PM

[-]
Who's Online
There are currently 1212 online users. [Complete List]
» 1 Member(s) | 1211 Guest(s)
Avatar

>