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

Phonograph motor fried??
#6

(05-30-2015, 01:37 PM)jerryhawthorne Wrote:  ODPILOT it seems you with help have figured out where the problem exists.  Indeed if the motor was wired direct someone had a problem with the selector switch.  I suspect the motor is just dandy and directing A/C directly to it , it will run.  Time to look at the switch.  Posting a schematic would help.
Best,  Jerry

OK - this thing is driving me crazy !!  I was able to hook up the phono motor to a previously restored 53-1750 (same exact model) and the motor powers up and runs fine.  So it's def not the motor.  The radio/phono selector switch tests as good as does the switch on the phonograph motor board.  So it's not the switches. Anyway, I've tried bypassing the switches/seletors - doesn't help.   On the formerly restored 53-1750, I get 118 Volts coming into the phonograph motor.  On the new one I am restoring, voltmeter reads 1.5Volts coming into the switch - something seriously wrong.  The positive wire for the motor is soldered into one of the pins for the 50y7gt (rectifier) tube.  This pin also supplies power for the dial light bulb - which works fine after the radio powers up. So I'm thinking it can't be the power coming from that pin or the bulb wouldn't work??   The grounding wire for the phono motor is connected into a bus terminal and that particular  terminal is connected  with a  .04uf capacitor to the ground AC power cord wire (another connection on the bus terminal)  AND this same ground terminal also has resistor which goes to a ground rivit in the chassis.  The ground rivet  seems to have good continuity and is not loose or corroded.    I've replaced the capacitor with a new one (I've recapped the entire radio) although I did not replace the resistor since it reads correctly (r-17 - reads 148 K ohms, supposed to be 150 K ohms.).   The insulation on all the connecting wires are good and the wires have good continuity.  So where is the problem - no freakin idea !!


Attached Files
.pdf SAMS_SCHEMATIC.pdf Size: 990.2 KB  Downloads: 948


Messages In This Thread
Phonograph motor fried?? - by ODPILOT - 05-28-2015, 01:02 PM
RE: Phonograph motor fried?? - by Warren - 05-28-2015, 02:13 PM
RE: Phonograph motor fried?? - by ODPILOT - 05-30-2015, 08:10 AM
RE: Phonograph motor fried?? - by jerryhawthorne - 05-30-2015, 01:37 PM
RE: Phonograph motor fried?? - by ODPILOT - 06-01-2015, 10:49 AM
RE: Phonograph motor fried?? - by morzh - 06-01-2015, 10:58 AM
RE: Phonograph motor fried?? - by sam - 06-02-2015, 03:14 AM
RE: Phonograph motor fried?? - by ODPILOT - 06-02-2015, 11:19 AM
RE: Phonograph motor fried?? - by morzh - 06-02-2015, 12:13 PM
RE: Phonograph motor fried?? - by sam - 06-02-2015, 07:01 PM
RE: Phonograph motor fried?? - by morzh - 06-02-2015, 08:31 PM
RE: Phonograph motor fried?? - by sam - 06-03-2015, 03:35 AM
RE: Phonograph motor fried?? - by morzh - 06-03-2015, 08:20 AM
RE: Phonograph motor fried?? - by sam - 06-03-2015, 11:26 AM
RE: Phonograph motor fried?? - by morzh - 06-03-2015, 02:12 PM
RE: Phonograph motor fried?? - by jerryhawthorne - 06-03-2015, 02:45 PM
RE: Phonograph motor fried?? - by morzh - 06-03-2015, 02:58 PM
RE: Phonograph motor fried?? - by jerryhawthorne - 06-03-2015, 03:36 PM
RE: Phonograph motor fried?? - by sam - 06-03-2015, 06:17 PM
RE: Phonograph motor fried?? - by ODPILOT - 06-03-2015, 08:06 PM
RE: Phonograph motor fried?? - by sam - 06-04-2015, 02:46 AM



Users browsing this thread: 1 Guest(s)