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I'm in the process of restoring the BOL record player on this model. There are two screw terminals on the backside of the chassis resembling what a standard antenna terminal strip looks like. This is shown on the components drawing on the attached PDF file of the schematic just to the left of the XXD tube socket. This is where the two thin wires from the tone arm get connected....one I believe comes from the photo cell, the other from the exciter lamp. My problem is I'm not getting any voltage readings from those two terminal strip connections. Which, of course, means the exciter lamp won't light when trying to play a record. Now just for an experiment, I took a 6 volt lantern battery, and gater wired the two thin wires from the tone arm to the two connections on the battery. Viola! The exciter lamp lit, and the BOL came to life, playing a record remarkably well with no adjustments or any restoration to the tone arm.
Does anyone have any idea what I could be missing that I'm not getting any voltage readings on those terminals? I did a preliminary check of the (#19) light reproducer coil and got continuity. Has anyone else had this issue on a BOL? This is my first BOL restoration. Thanks!
http://www.nostalgiaair.org/pagesbymodel...013445.pdf
Greg V.
West Bend, WI
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grrr darn it how is it I can`t find one
greg
is this what your talking about
[Image: http://i1303.photobucket.com/albums/ag14...o5edcj.jpg]
if so
green wire outer case of rca to left side photo cell
white wire center tap of rca to right side of photo cell
black wire chassis ground screw #1 to lamp ground
tan wire power screw #2 to center tap of lamp
pretty simple color of wires hard to tell though
are you getting power and good negative coming from chassis
sam
Some day, and that day may never come, I will call upon you to do a service for me. But until that day, accept this justice as a gift
mafiamen2
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Thanks, Sam. I finally got to snap a few pictures. It's very similar....
Only the RCA jack port is in the audio transformer at the bottom of the cabinet, this being the transformer for the phono arm. You can see it next to the chassis in the photo, sitting inside the cabinet loose. The two terminals are marked "Red" & "Black" corresponding to the leads from the BOL tone arm. The 3 prong port next to the terminal must be for an external antenna attachment.
There are three wires connected to the two terminals. One goes to the BOL light focus adjustment on the back side of the chassis, one goes to a terminal strip near the XXD tube, and the other goes to the light reproducer coil (#19 on the schematic). The problem I'm having is these connections to the terminal are not shown on the schematic. At least not that I could find. I ordered a set of schematics from Chuck and he had the exact same pages I already had... taken from the 1941 Philco "Yearbook", which I also have an original copy of. I will have to do some more wire tracing from these points and see where they end up. And wire replacement...
Greg V.
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OK, I now am able to get voltage from the two terminal screws, and am able to light a #55 bulb in a socket connected to those two terminals. BUT, I cannot get the "exciter lamp" in the BOL tone arm to light when connected to those same terminals! Yet I can get the exciter lamp to light when connected direct to a 6 volt lantern battery. So my theory is someone replaced the original bulb in the BOL arm with a bulb rated at too high of an amperage. I'm only getting 4.7 volts off of the two terminals, and it takes 6 volts to light the exciter lamp. I would like to try replacing the bulb with a #55 but I cannot get the socket out of the exciter lamp tube on the BOL arm. The rubber mount around the socket is not budging. Can anyone give me any tips on how to safely remove that rubber surrounded socket without damaging anything?
Greg V.
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hey greg
so your getting almost 5 volts to light but it works with 6volt battery
you need to see why your not getting 6volts #66 adjustable resister good ?
sounds like your not getting correct voltage
and they are special bulbs I think
they are hard as H**l some times to get out little heat maybe
sam
Some day, and that day may never come, I will call upon you to do a service for me. But until that day, accept this justice as a gift
mafiamen2
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hey greg
how did you make out with it
sam
Some day, and that day may never come, I will call upon you to do a service for me. But until that day, accept this justice as a gift
mafiamen2
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The original Mazda bulb (with a straight filament) was designed for a max voltage of 3.3 volts. The energy for this bulb is RF (I think) originating in the radio chassis and is adjusted via a compensator. My guess is that the radio cannot supply the kind of voltages you are talking about. If your bulb has been changed you might need to find one closer to the specs of the original Mazda. I don't know the how a 55 matches up to that. Check out the info on Philco Repair Bench regarding the BOL lamp.
The original gum rubber that holds the bulb assembly inside the tube is likely disintegrated and is "stuck". You might just have to expect that with difficulty you will get it out, and will need to find something to replace it with. If you are lucky a small piece might be salvageable to still use to seal the tube.
marv
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I did manage to replace the bulb with a #55 and the bulb works fine, but the radio is still not putting out the voltage needed to light it. So, for now, I created a simple external power supply with diodes to light the lamp, and wired it into the power for the turntable motor. Alas, this works, but I'm not getting the volume out of the speaker that I should be when playing a record. I suspect the photo eye is weak. The #55 bulb is rated at 7 volts, and I'm getting 6 volts with the power supply, which is almost double of what the original bulb was putting out. So I should be getting the volume necessary. I ordered one of the photo cells from Japan I see some previous posters here have used as a replacement, so we'll see if that makes a difference.
Greg V.
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greg
if your using old original photo cell forget it they don't work
did you replace rubber at needle assembly that's hard as rock now
and has some thing to do with the sound too
don`t give up
sam
Some day, and that day may never come, I will call upon you to do a service for me. But until that day, accept this justice as a gift
mafiamen2
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Sam, Just curious what you've used to replace the old original photo cell on your BOL? I'm a little concerned about the photo cell I ordered from China. The seller on eBay has been racking up more neg's the positives in his feedback as of late.
Greg V.
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Some day, and that day may never come, I will call upon you to do a service for me. But until that day, accept this justice as a gift
mafiamen2
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Thanks, Sam. Yes, that's the one I purchased. And paid for expedited shipping. It was supposed to arrive by the 29th. No dice. And now when I click on that link it says "This listing was ended by the seller because the item was lost or broken". I've read his feedback and it seems other's have had problems with him not shipping or the item not arriving. I hope I'll receive it yet.
Did you attach yours to the old photo eye with glue or double sided tape?
Greg V.
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Greg
Used thin double sided tape
put right over old one
Sam
Some day, and that day may never come, I will call upon you to do a service for me. But until that day, accept this justice as a gift
mafiamen2
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greg
how did you ever make out with this
sam
Some day, and that day may never come, I will call upon you to do a service for me. But until that day, accept this justice as a gift
mafiamen2
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Never got the photo cell from China. The seller said it was no longer available and refunded my money. So the set is running on the original photo cell. It works, but the player doesn't have the volume output it should. I'm happy with it for now, though, until a different newly-manufactured photo cell can be found.
Greg V.
West Bend, WI
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