[Eric]

I have a Crosley 515 been working on it for a while here is the link. http://www.nostalgiaair.org/PagesByModel...003373.pdf

I get no sound, hum or static.

Here is the what I've found so far. the speaker coil was open so I wound a new one and it reads 1048 ohms the choke is 538 ohms and I get continuity on the voice coil.
Tubes tested good.
the ant coil was open so I wound a coil with the taps per the print I'll strip the old one and take accurate data later if I can get some sound
I recapped and as I was checking the resistors most were way out so I replaced all of them except#20 the flex which was good and 21Z & 21Y(wire wound mounted on the back wall of the chassis) were open and I replaced them with ceramic 5 watt resistors.
The vol is 0-30k
Checked Continuity through 1st, 2nd IF and OSC and they look to be good (I have the resistance values)
The socket voltages were taken with the vol at max and there all with in 10% the one question I have here is on the 6D6 IF SU & K I can very that with the vol control and it goes from 0-94v?
I put a signal gen at the G on the 6B5 I get a very faint hum.
On the Filter caps 6Z the + is connected to the 80 heater neg to chassis
the 6Y the + to the circuits and the neg to the chassis is this right? I get 6z 277vdc & 6y 211vdc on the + side.
Went with a red pencil component by component and found some mistakes and corrected them
everything else looks good where do I go from here?????

Eric

[morzh]

>>>the one question I have here is on the 6D6 IF SU & K I can very that with the vol control and it goes from 0-94v?

Eric

This I did not understand. In any case, try not to use cryptic messages; troubleshooting itself is hard enough.

Both 6Y abnd Z should have their plusses to Chassis, that's correct.

>>>The choke is 538 ohms

What choke? I don't see any. There is the voice coil, and there's the output Xfmr, no chokes there in that schematic.

[Eric]

Sorry for not being clear comes from being new but I'm learning.
On the 6D6 IF the socket voltage chart says I should have 3 volts but if you turn the vol control I can go from 0-93v.

No choke it is an output transformer mounted on the speaker.

[morzh]

It pays to tell which voltage, it lists two, though they are connected together (sujppressor and cathode). Try to be exact, name the electrodes.

Now the voltage will change. I do not have the values, but the B+ voltage gets divided between the series 21Z-21-Y and the portion of 31Z volume regulator to the GND.
If you have values, calculate how much the change is.

[Eric]

on the 6D6 IF pin 4(su) and pin 5(K) are tied together then wouldn't the voltage be the same at either pin?

I measured the voltage drop across 21Y is 119v and the drop across 21Z is 99v (vol at max)
I have been setting the vol control at max is this correct?

[morzh]

Eric, yes this is what I said before - they are tied together. Obviously the voltahe then will be the same.
I do not know whether there is a rule of setting the radio controls when measuring voltages and if that involves setting the volume control to max.

If this is the case then yes, the voltage at the Cathode and Suppressor will be at the minimum, as the Chassis through the wiper connects practically directly to that point. Usually the potentiometer will have some residual resistance there, not exactly zero, so this probably will cause the voltage to be a bit different from zero.
At the minimum volume the voltage may be high but again, without knowing the values (this document lists only part numbers) I cannot tell you what it will be.

if you know the B+ voltage and all the resistors' values, plus the full scale value of the volume pot, then you can easily calculate it as V=(B+ * Vol_pot)/(21Z+21Y+Vol_pot).

[Eric]

Warning your dealing with a dumb a** but here it goes
B+=229
229x30000=6870000
25000+8500+30000=63500
6870000/63500=108
vol pot 30000
21z=8500
21Y=25000
is this right
Was tracing wiring this morning lookiing for any mistakes I might hat made and hooked up a signal gen to the ant term through a .02cap with the gang closed and got a faint buzz at 455 at the low end of the vol pot??

[morzh]

Eric

Considering tolerances this is a good agreement. Also the 21Z/Y are parallelled by tubes' screen grids so that lowers their resistances some resulting in higher voltage than calculated. Without the tubes the result, if the tolerances are good, would be closer.
So, yes what you see is OK.

[Eric]

I was doing some searches on the Antique forum and came across some info that says the vol control should be 15k and not the 30k that is in the chassis so I will see about picking up one tommorow.

found some more info apparently Crosley also made this radio for United Motors model Delco 1105 their print shows a 4800ohm vol control. The print looks the same just layed out a little different it has the values on the schematic I will make a closer comparison tomorrow

[morzh]

Which does not mean it should not work at all. Not correctly at the min.to mid. volume position, but at the max it should be OK (and the voltage should be very low).

[Eric]

Delco print calls for 4800 ohms I put in a 10k all I had the 30k was definatly not orignal.

The ant coil was open when I started this project I wound one estimating the turns not wanting to completely destroy the coil when I take data just yet. I feel I should still get sound. Am I wrong?


Just took a new set of socket voltages I'v got two things that are a problem
the 76 Plate should be 86v I get 156v and the
6D6 IF SU&K are .06v
the rest are 10% or less
Vol is at max and the gang is closed

Should I be looking at the 2nd IF?

[morzh]

At vol at max the SU&K voltage should be what you have, more or less 0V or close, so it is OK.

Check res. 17 for the value (see if it is different from 300K I think it should be) and the 11Z cap for leakage to see why the 76's Plate is low.
Also check coil 4, the right part (the one going to the 76's grid) for being open, and the res. 19 for not being 1M.

[Eric]

I have a question?

"11Z cap for leakage to see why the 76's Plate is low."
The plate on the 76 should be 86v and I got 156v??

Will check what you have said in the morning. Thanks

[morzh]

OK, misread it. Mea culpa.

Q: Is your phono adapter pins strapped together like they should be when the adapter is not in use?

[Eric]

It's not there.