selection problem wurlitzer 2150

Hello ,

i'm restauring a wurlitzer 2150 and it's working very well when I make a selection by pushing a pin from the selection wheel with my finger. The mechanisme is thus ok and the amplifier is also working very well afther a complete strip-down ( i've changed all the wires and the condenser + a few resistors)
I've measured the voltages that I need for my selection and I have both 24VAC and 45VDC at my bridgerectifier.I yhink this is ok. I also measured all the solenoids that are needed for selection and they are all ok.
When I push the free play button I hear a few solenoids cliqing and then the light from "make selection" is burning now. At this moment I can make a selection for example A1. But afther this nothing happens. I've allready searched but I cannot find anything that's wrong.I have the manual with the schematics but it's not so easy because it's the first wurlitzer that I'm working on.
Can anyone help me?

Greetings from Belgium , Peter

Hello Peter

We have to check some things first. When you push the free play button, "make selection" should light up and the Latch Solenoid should pull in. If you push anumber and a letter key, they must lock and stay locked, until the selecton is registred. Further one of the small number solenoids (according to the pressed number key) should pull in and the selector motor should start running. Please check, if this is working or not.

The DC voltage is much too high. It should be about 30 volts (the servicemanual says - 28 volts)

Greetings from Ausria - charly49

Hello Charly49,

thanks for the reply , It's like you say , when I use the free play button , the light "make selection" lights up and I can make a selection by pushing the number and letter key. The keys stay locked but further there's nothing more that follows , The solenoid will not pull out and the selector motor is not running. I've tested the motor on an extern supply and it is working well.
What concerns the DC voltage , on the schematic is written that on the 2 middle pins from the bridge rectifier comes 36 V . I thought that is was normal then that the voltage measured between + and - from the rectifier is always higher , or perhaps i'm wrong? I will look at the manual to see if I can find something btween the 28V you mentioned.

Greetings , Peter

Hello Peter

When a letter and a number button are pressed, Timing Relay TR2 (inside the Junktion Box) should be actuated. The current therefore goes from the bridge rectifier to the 3/10 A - fuse (on the Junktion Box), the coil of TR2, to one of the Number Select Coils (which should pull in), to the button switch, to the Numbers Latch Switch, the Letters Latch Switch and then to ground. Somewhere in this circuit the current must be interrupted. I think, it's the fuse or the latch switches.

According to the manual the DC voltage should be 28 volts. Therefore the AC voltage on the rectifier connections must be about 20 volts. If the voltage is higher, a circuit error probably exists.

Greetings - charly49

Hello Charly49 ,

I've looked in the manual and you where right , the DC voltage must be 28VDC. I know now wat i've done wrong. Because the original selenium rectifier was broken I had to replace it by a modern silicium rectifier . that's why my DC voltage was to high. I've replaced the condenser 500 microfarad/50V by a 50 microfarad/63V and now my DC voltage is 27.5 VDC.
I also measured the circuit that you where explaining and I noticed that when I take the common from the number bar and put it to the ground that then the number coil that i had pushed in was working and that also TR2 worked. It only works when I take a wire from the common to the ground.
I didn't find out yet why this is so. Perhaps you have an idea?

Greetings and thanks for helping me , Peter

Hello Peter

The common from the Number Button Bar goes to the latch switches. The latch switches have to complete the circuit to ground. The latch switches will be closed, if both a letter and a number key are pressed and latched. Check the latch switches. One of it (or both) will be dirty or badly adjusted

Greetings - charly49