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I have been doing reasearc on my radio and found out that it is in better condition than I speculated. With this knowledge I believe I might be able to get the phonograph working, however I can't find much information on the radio. I found some schematics but I don't know how to read them. I read that my model has a crystal cartridge which by now is most likely "dead". I can't find a manual or step-by-step instructions helping me to take the insides apart and removing the cartridge. Does anyone know anything about how to take these apart? If so can you please help me.
Thank you.
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Reading schematics in itself is fairly simple: it is a graphic representations of the parts and their interconnect.
The parts are self-explanatory, and in old schematics there are very few:
A resistor - sawtoothed element with two pins
A capacitor - two parallel lines with two pin
A choke (or an electromagnetic coil) - several semi-circles back-to-back with two pins.
A transformer - several chokes with the common core shown (the chokes are aligned along it)
A tube - an often encircled (or en-ovalled, or even without border shown sometimes) element with electrodes, the dashed lines being grids, the bracket (or an arch above the filament) being the Cathode, the angle under the Cathode with two pins attached being the filament and the very top, one line with the pin attached perpendicular, being the Plate or Anode.
An incandescent lamp is self evident, a switch is also self evident.
The lines connecting pins represent wires, the tie-dots (small solid circles superimposed on a crossing point of two wires) shows a physical connection of the wires. No tie-dot means no connection, the wires simply unrelated and the crossing does not even imply that they cross in the physical world. Sometimes to make it clear such a no-connect crossing is marked with one wire line forming an arch over another, as if in the real world it just went over with a slight bend.
It is tracing and understanding what the elements do when connected that will pose a challenge.
Which we won't be able to explain here - this is what books and some specialized websites are fore.
Another thing is, you have to realize that without any experience you are exposing yourself to a danger of electrocution as the tube devices typically run using very high voltages, up to 400V or so DC. This can easily kill you. or give you a nasty shock. Even if you quickly familiarise yourself with elements' behaviour there is still that lack of experience when you simply do not anticipate certain things.
Despite folks here usually cheering for novices, I do not consider a tube radio restoration a good learning project for a person thoroughly unfamiliar with electronics or electricity.
nevertheless, I suppose you will soldier on with restoration and rest assured we will be helping you along the way but before you embark on this quite perilous journey I strongly recommend you at least read some basic things, get some basic tools and learn how to use them.
Another thing to suggest, do not create two separate topics when one would suffice, we could very well proceed with the previous one, as it is the same radio and the topic has just started.
There are no such thing as a step-by-step instruction for repair of every chassis (although there are those for aligning them), but I am sure that at least for some phonographs, for their mechanical part at least, there are such instructions and, if you are lucky, someone here or elsewhere might have them for your radio.
Now, a safe thing to do, even without the knowledge of electronics, is recap, that is changing old capacitors. There is plenty of material here on this website as to how it is done.
As questions, ask plenty of them, do not assume you understand everything - people with more experience than yours get surprise or two when doing it.
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First of all I would like to thank you for taking your time to respond so in depth. I appreciate that very much. Second thank you for explaining to me how to read these schematics I think with a little practice I might be able to understand them thoroughly. I would also like to thank you in giving me all of the danger involved in fixing this. Thank you soooooo much!
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The schematic for that can be found
here. You need to download a DJVU reader you should be able to down load a browser plug in
here.
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There is a how-to on rebuilding crystal cartridges
here, authored by Syl Vanier.
However, please note that this is
not for the novice - it is for the intermediate to experienced collector/restorer. I've been messing with old radios since I'm 14 years old - almost 41 years now - and I have yet to try Syl's method (or anyone else's, for that matter) of rebuilding cartridges. I admit that I'm a bit intimidated by the thought of trying it.
--
Ron Ramirez
Ferdinand IN
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Thank you for the useful information, I will look for somebody with more skill than I. Thank you so much!
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Some folks have trouble making the DJVU plug-in work. If that's the case you can download the DJVU file and convert it to PDF at
http://www.djvu-pdf.com/ . Ron has some
repair vendors on this site as well.