Hope I didn't make too big a mistake with my radio...

[Soulwyvern84]

I asked about how to convert a transistor radio into an amp before on this site, I've been reading more about electronics and watching more videos so I may have gotten myself in a pickle by trying it out. I disconnected a diode to try to stop the radio function, when that didn't work I cut a cable that put a stop to the radio. I am wondering if I need to go back and replace the diode that I disconnected before going any further? The radio is an RCA model RZG 133 ex.

 

[Alec_t]

Without a schematic it's anyone's guess as to how best to do the conversion. But is the conversion worthwhile? Most transistor radios have only a modest output level and are far from hi-fi.

 

[Soulwyvern84]

I like the old vintage snarly sound they have. I like the idea of a portable amp that I didn't pay too much for. Besides, it's fun to tinker. I'll try to load some pictures of the diode that I don't think was supposed to be disabled.

 

[Soulwyvern84]

here are some pictures, I'm going to try to hunt for a schematic too.

 

[(*steve*)]

This images are not in focus and don't show anything obviously interesting.

Perhaps better photos with some explanation?

 

[Soulwyvern84]

i was just trying to show where i disconnected part of a diode. I don't know what type it is. I am kind of lost. I'm new to all of this still...

 

[Soulwyvern84]

sorry they are so blurry I took them with my phone and have bad lighting in my room.

 

[73's de Edd]

Mme Soulwyvern84. . . . . . .

I think I remember your being here BEE-4 . . . and you were wanting to only use the amplifier aspect of a radio.
You were probably attempting to silence the radio portion of the unit by a disconnect of the detector diode.
FAR better,that you just detuned off of any station, while tuned on the low end of the broadcast band.
You will need to put that "war" back where you took it loose from. . . .to make the radio . . .radiate again.
I have a schematic of that RCA unit, but will need a week for the high water to go down out at the "mule barn"
where my accumulated VEWY-VEWY old documents . . . much like me . . . .are being archived and stored.



73's de Edd

 

[Soulwyvern84]

thank you, and I think I might have accidentally disconnected a resistor thinking it was a diode. it has 4 bands on it green, blue, red and silver. I did get the radio function off by disconnecting a wire. But before I do anything else I wanted to know what I did when I disconnected the resistor.

 

[Soulwyvern84]

I hear a little bit of static when I turn the knob so I think it would work as an amp once I solder the jack to the volume knob. It's just bugging me that I messed up. I did cut the ac cord before trying anything and used batteries after. I was just wanting to try it so bad.

 

[Mongrel Shark]

I can just make out a blurry broken resistor or axial inductor near a blurry finger in a blurry photo.

Its not a diode.

What made you pick that resistor over all the diodes you had to choose from? This info will help work out where you started to get lost...

I learned the hard way like you (some 20 years ago, starting when I was 8). I'd recommend starting by learning to fix what you broke. Which means learning what that part does in the circuit.
Then you are free to try again. You'll break something else unrelated to your amp quest. Then learn to fix that. Rinse and repeat a few times and 6 months from now you will be able to fix or rebuild any part of that radio, but you will still be lost as to how to make an amp out of it.

Then maybe if your really smart (and mostly patient and observant). You will learn to build a simple pre amp or similar, and you will start to see the circuit you need in the radio and you will realise whats radio and whats amp and that you can just detune the radio and inject a signal at the right place just like 73's de edd sugested.
Or even eaiser. Just grab 2 npn transistors and a resistor to make a really crude Darlington pair pre amp. It will sound even tinnier than your crystal set. Plus it turns into a smoke machine and light show if you turn it up enough.

 

[elebish]

This images are not in focus and don't show anything obviously interesting.

Perhaps better photos with some explanation?

That was not a diode, it was a 5600 ohm resistor. Re-connect the resistor and disconnect the detector diode that follows the IF section. Couple your audio through a 4 ufd @ 25 vdc across the 2 outside terminals of the volume control. Make sure the (ground) negative side of audio input goes to the negative (ground) terminal of the volume control. The capacitor is to block any dc from getting into the audio amp. This is not the scientific way to do this since I don't have a schematic but should work.

 

[Soulwyvern84]

thank you all for the advice. I'll hook the resistor back up and go from there.

 

[Soulwyvern84]

Update* I soldered the resistor back and soldered the 1/4 jack up and the radio is now an amp and it's neat, not very loud but very interesting. Thanks guys!