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

46-1201 model 128 restore and question
#16

If resistor 27 is completely open, that will certainly cause a problem, but then you would have no voltage at all on the plate (pin 2). You can try replacing it and see what happens.

I would also try to trace out the wiring to pin 7 and see why there is voltage present there. Pins 4 and 7 should be connected together inside the 7C6 tube, so there should be no voltage between them.
#17

Sooooo, apparently i've made a faux pas. The last 3 tubes i mixed up. Sorry about that. The readings seem much better now. Here's the new readings.

   
#18

That's much better. Now it looks like resistor 27 is really the problem. You only have a half a volt on the plate pin 2 where there should be 55 V.

An open resistor 27 would be the cause since it should supply plate voltage to pin 2.
#19

+1 for Mondail, smarter than me. The new measurements really focus on that tube and #27 resistor. Now the voltage is going low, prior readings were going high.
Jerry

A friend in need is a pest!  Bill Slee ca 1970.
#20

Yup, replaced #27 resistor and lots of volume! had to remove the cone to get all the grit and metal particles out of the center but sounds great now except for some buzzing and humming depending on the station tuned in. Could this just be an alignment issue? I still have some resistors i want to replace because they're over 10% off.




Users browsing this thread: 2 Guest(s)
[-]
Recent Posts
PT-6 antenna connections
Notice in the schematic the notch at the bottom of the antenna coil is between pins 3 & 4. Yes, pin 6 of the 7C6 is...RodB — 07:34 PM
bridkarl
I have two PT-6 chassis. On both there is a blue wire that runs from the above chassis transformer to pin 6 of 7C6. So t...bridkarl — 07:23 PM
Cannot Adjust an IF Transformer’s cores
Joseph, now you are an engineer!!RodB — 06:37 PM
PT-6 antenna connections
Hi, reading your explanation I can see the confusion. If you take it one connection at a time it should result in a desi...RodB — 06:34 PM
Cannot Adjust an IF Transformer’s cores
It works! I received the PCBs this morning in the mail, and put everything together. I reused the base from the original...jrblasde — 04:32 PM
PT-6 antenna connections
I seem to have lost my way on this PT-6. I see the antenna aerial transformer schematic - I’m reading pins 1 through ...bridkarl — 12:30 PM
40-150 General questions
Good thing you're a good electrician ... the pictures show a lot of rewiring in your future! Take care and BE HEALTHY!...GarySP — 11:52 AM
40-150 General questions
I think RobB has it right. It is a part number and looks like its stamped on the chassis and that wasn't something you ...klondike98 — 11:41 AM
40-150 General questions
It's most likely a part number. Most of Philco part numbers are in that format. I looked at the parts list for this mode...RodB — 08:10 AM
40-150 General questions
Hi Kevin, No, I don't but I like your Quote about being a good electrician. The way I look at it is "The fact ...MrFixr55 — 08:06 AM

[-]
Who's Online
There are currently 3254 online users. [Complete List]
» 3 Member(s) | 3251 Guest(s)
AvatarAvatarAvatar

>