Posts: 661
Threads: 141
Joined: Jun 2011
City: Elko,MN.
Hello guy's,
Have been working on this K130 console,and found the right capacitor for the electric tuning motor.
Installed it and the motor now works.
However if you push one of the station pushbuttons it will just motor across the dial until it hits the end of dial,then the motor keeps spinning but it does not reverse.
Is there some kind of sensor that reverses the motor at the ends.
Don't know how the station pre-sets are set to specific stations either.
I also noticed that the chassis gets hot to touch over in the corner where that long strip resistor is mounted with the R24,R25,R26 and R28 resistor hookups are.
Is it normal for these to get hot?
Have replaced a bunch of wiring on this set.Now it looks like the tuning eye tube wire harness is bad and the tube socket is brittle.Not sure if I can get that apart without breaking the plastic socket.
Anyway,If anyone has any suggestions for any of these problems,it would help.
Thanks
murf
Posts: 337
Threads: 15
Joined: Nov 2005
City: Ortonville, MI
All of those motor tuning systems have limit switches at the ends of the dial travel, to cause the motor to reverse and hunt the other way. You'll need to look for them and use contact cleaner, such as De-Oxit., and get the contacts working again.
I have some of those RCA tuners on sets in my collection, but one is not easy to get at and look at just now. The service notes in the RCA red books, if you have access to one, will be a big help.
Posts: 661
Threads: 141
Joined: Jun 2011
City: Elko,MN.
Doug Houston Wrote:All of those motor tuning systems have limit switches at the ends of the dial travel, to cause the motor to reverse and hunt the other way. You'll need to look for them and use contact cleaner, such as De-Oxit., and get the contacts working again.
I have some of those RCA tuners on sets in my collection, but one is not easy to get at and look at just now. The service notes in the RCA red books, if you have access to one, will be a big help.
Will look for the switches Doug.
Thanks
murf
Posts: 149
Threads: 4
Joined: Oct 2005
City: Sullivan, MO
There are no limit switches on that tuner. The large metal contact disk on the back of the tuner is separated into 2 segments with an insulator separating them. Depending upon where the selected preset is and where the tuner is when you select that preset, one section of the disk or the other will be selected. These segments determine which direction the motor turns to get to the correct position on the dial. Read page 15 of this service information on how the mechanism works and how to set it up.
http://www.nostalgiaair.org/PagesByModel...015848.pdf
When the dial is set to the station you have selected by its respective push button, the pin contact on the back of the tuner should be on set on the insulator. You may need to pull the contact pins out and file them to a point so they don't overrun the insulator as the motor is moving.
Sean
WØKPX
Posts: 661
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Joined: Jun 2011
City: Elko,MN.
Sean Wrote:There are no limit switches on that tuner. The large metal contact disk on the back of the tuner is separated into 2 segments with an insulator separating them. Depending upon where the selected preset is and where the tuner is when you select that preset, one section of the disk or the other will be selected. These segments determine which direction the motor turns to get to the correct position on the dial. Read page 15 of this service information on how the mechanism works and how to set it up.
http://www.nostalgiaair.org/PagesByModel...015848.pdf
When the dial is set to the station you have selected by its respective push button, the pin contact on the back of the tuner should be on set on the insulator. You may need to pull the contact pins out and file them to a point so they don't overrun the insulator as the motor is moving.
Hey Thanks Sean.
Will look again and see whats happening.
Right now it just travels to one end or the other,and then the slippage of the tuner cord keeps it from breaking anything.
You would think it would reverse itself after hitting the end of the travel.
Do you know if it's normal for that long strip resistor mounted to the back of the chassis should get hot?That area of the chassis will get hot after playing for a while.
Have a great day Sean,
murf
Posts: 149
Threads: 4
Joined: Oct 2005
City: Sullivan, MO
It is not unusual for that resistor to get hot. One section is dissipating 8 Watts and another is about 3 Watts. They use the chassis as a heat-sink to draw the heat away.
Sean
WØKPX
Posts: 661
Threads: 141
Joined: Jun 2011
City: Elko,MN.
murf Wrote:Sean Wrote:There are no limit switches on that tuner. The large metal contact disk on the back of the tuner is separated into 2 segments with an insulator separating them. Depending upon where the selected preset is and where the tuner is when you select that preset, one section of the disk or the other will be selected. These segments determine which direction the motor turns to get to the correct position on the dial. Read page 15 of this service information on how the mechanism works and how to set it up.
http://www.nostalgiaair.org/PagesByModel...015848.pdf
When the dial is set to the station you have selected by its respective push button, the pin contact on the back of the tuner should be on set on the insulator. You may need to pull the contact pins out and file them to a point so they don't overrun the insulator as the motor is moving.
Hey Thanks Sean.
Will look again and see whats happening.
Right now it just travels to one end or the other,and then the slippage of the tuner cord keeps it from breaking anything.
You would think it would reverse itself after hitting the end of the travel.
Do you know if it's normal for that long strip resistor mounted to the back of the chassis should get hot?That area of the chassis will get hot after playing for a while.
Have a great day Sean,
murf
Well,tried removing pins and putting a point on them to no avail.
Still skips right past the gap in the disc.
I suppose I could try re-wiring the contacts.Have found lots of bad wires on this set which I have had to replace due to crumbling insulation.
Otherwise,I think I will disable the electronic tuning and forget about it.
Thanks
murf
