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

RF coil has resistor
#1

Hi All;
Can anyone tell me WHY the Primary coil of the RF transformer has a 10K Resistor accross it ?? The primary coil measures 38.6 ohms and the secondary coil measures 4.6 ohms.. The Primary coil is wound inside of the coil form in that cross hatch type of winding.. The Secondary coil is wound on the outside of the coil form..
The other set that has the same type of Mixer Tube 1C6, a Philco 39, which is a two band set against this which is a four band set.. The circuit is easier to follow on the two band set, and it looks like the Oscillator circuit is the same between the two, except that one is a four band set and the other a two band set..
THANK YOU Marty
#2

Please post schematic or link. Cold be limp attempt as a "fusister."
#3

Hi All;
Codefox, I would think that this is too old of a set to have a fusistor..
Here is the link for the Philco 34
http://www.nostalgiaair.org/Resources/185/M0013185.htm
And here for comparison here is the link for the Philco 39
http://www.nostalgiaair.org/Resources/265/M0013265.htm
My guess is for when the signal would be too strong, so as not to overload the RF transformer.. Or possibly some kind of Damping effect..
THANK YOU Marty
#4

That's often done to knock off the Q of the coil. Sometimes good RF selectivity is not a good thing since its variable across the band. And in a production environment it can create alignment headaches.
#5

Hi All;
Exray, Thank You, that is exactly what I needed to know.. I just fired up the set, with the Resistor disconnected on one side, just to see If it would make any difference.. I still just get a hum, my set doesn't know the Tune, either..
I will re attach it and try again..
I also will look at the Oscillator with my scope and see what I get..
Thank You Marty




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Road Trip for a Philco 46-480
Good morning, folks! I’ve finished the cabinet and the electrical restoration, and have detailed those in their respecti...jrblasde — 10:56 AM
Studebaker/Philco AC-2687 car radio
Arran, Thanks for checking you manuals. I appreciate that. Let me know what you find. PhilPdouglaski — 08:46 AM
Studebaker/Philco AC-2687 car radio
I have some car radio service manuals, Riders I think (not to be confused with the big blue binders), so I may see if on...Arran — 01:20 AM
Philco model 40-100
Greetings; Here is an update, I found a listing on fleabay for a similar chassis to yours, and it has a photo of what...Arran — 12:58 AM
Philco model 40-100
Greetings; I think I may have found a clue as to what is missing, from a search I made, there is a rear view of the c...Arran — 12:12 AM
Philco model 40-100
I recently acquired a Philco model 40-100 farm (battery) radio. The radio was in very good condition except the red on f...mhamby — 05:59 PM
Studebaker/Philco AC-2687 car radio
Hello, Richard the radio is an AC-2687 Studebaker model. The Philco model is S -5323 and the chassis p/n is S-5523Pdouglaski — 11:52 AM
48-482 rear panel help
The 48-482 is an AC only set as well, featuring a power transformer. While the transformer shouldn’t get “hot”, it is ye...jrblasde — 11:12 AM
Studebaker/Philco AC-2687 car radio
I gave a Chrysler/MoPar car radio from 1954, it was made by Philco, and it uses two chassis, one has the power supply an...Arran — 11:06 AM
48-482 rear panel help
Hello keithchip. You could make a hardboard back for the set, but make sure you provide plenty of ventilation holes in ...GarySP — 11:04 AM

[-]
Who's Online
There are currently 2363 online users. [Complete List]
» 2 Member(s) | 2361 Guest(s)
AvatarAvatar

>