Add LEDs to Vintage Radio?

[w0z]

You can drive the LED directly from the AC just need a resistor or capacitor.

Not recommended, definitely not recommended don’t even think about it, it might work briefly with some leds but you’ll see them off with reverse voltage and they will flicker.

 

[w0z]

The driver looks like it is constant voltage not constant current so you will need to connect the led's in parallel not series.

If the leds are all the same you can connect in series, with an appropriate current limiting resistor, they will each drop the same volts. The supply mentioned by the OP may not be well regulated hence the need to start with a higher value dropper and check current then adjust R to suit. Yes he could tap off the 6.3v heater suppy(assuming it is 6.3), with a 1N4001 diode and a 100uf C, and if necessary a dropper R which would smooth, but he said he’d bought a 9v supply

 

[mainline]

Not recommended, definitely not recommended don’t even think about it, it might work briefly with some leds but you’ll see them off with reverse voltage and they will flicker.

Not ideal, no, I didn't say it would be, but it's common practice on mains relays to show when powered.

If the leds are all the same you can connect in series, with an appropriate current limiting resistor, they will each drop the same volts. The supply mentioned by the OP may not be well regulated hence the need to start with a higher value dropper and check current then adjust R to suit. Yes he could tap off the 6.3v heater suppy(assuming it is 6.3), with a 1N4001 diode and a 100uf C, and if necessary a dropper R which would smooth, but he said he’d bought a 9v supply

The Op has a power supply which is constant 5 volt, not 9 volts. I'm pretty sure it would be regulated. The LEDs would need to be in parallel, not in series. They already have a current limiting resistor which should work between 3 and 12 volts.

 

[mainline]

Hi all. I am trying to figure out how to add a few amber color LEDs to a 1953 Zenith K622 radio. One to light the tuner, one for the clock and one behind the center grill. I've gone down some rabbit holes. At this point, I would tap the original 110vpower and connect an 110v AC to 9v DC step down power converter then, from that, parallel wire three LEDs after three resistors. Does this sound right???

Worth a watch

View: https://www.youtube.com/watch?app=desktop&v=Q23uh7AjjXw

 

[mainline]

Here is the radio and also the parts I bought. I am going to tap into the 110v power cable then run it to the power converter then to the LEDs. They have resistors on them. I think this will work. View attachment 121795
View attachment 121796

You may find that the Smps will cause interference to the Radio.

Personally, I would have endeavoured to fit lamps or Nixie Tubes instead of leds.

​

 

[Avo Mk8]

T524R Ch= 5L07 Radio Zenith Radio Corp.; Chicago, IL, build 1954 ? |Radiomuseum.org

T524R Ch= 5L07 Radio Zenith Radio Corp.; Chicago, IL, build 1954 ?, 8 pictures, 10 schematics, 5 tubes, United States of America , semiconductors, Broadcast

www.radiomuseum.org

(Above not exactly the same clock)

Just a mention re safety:
There have been a couple of mentions of "mains transformer" etc., but this is what I knew colloquially years ago as an AC/DC set. There is no mains transformer. The valve (or tube!) heaters are high voltage and connected in series across the mains, possibly via a dropper resistor if the voltages don't add up to 110/120V!
I'm pretty confident about this because the one valve I can easily see the number of (50C5) has a 50V heater.
The chassis is often connected directly to one side of the mains. If the set is on a 2-pin plug, it's pot luck if the chassis is live.

 

[ScottCash]

Hi all! Thanks for all the great responses and advice. You guys are a wealth of knowledge. I'm not afraid to admit I am a total newb to this stuff so I appreciate the input. Here are the circuits wired up. 2 leds for each side and 4 behind the speaker in the middle. So, more than I originally planned but should look cool. I added a dimmer for each. I'll post some pics when it is all put back together.

 

[w0z]

Not ideal, no, I didn't say it would be, but it's common practice on mains relays to show when powered.



The Op has a power supply which is constant 5 volt, not 9 volts. I'm pretty sure it would be regulated. The LEDs would need to be in parallel, not in series. They already have a current limiting resistor which should work between 3 and 12 volts.

yep sorry when I replied I hadn't seen the photo of the parts, and the OP originally said he had a 9v supply hence my reply.
I agree filament lights would probably look more authentic
On a slightly different note if he is intent on the leds he might need to distribute the light and use several, (perhaps a perspex diffuser)
I like the radio...

 

[w0z]

Hi all! Thanks for all the great responses and advice. You guys are a wealth of knowledge. I'm not afraid to admit I am a total newb to this stuff so I appreciate the input. Here are the circuits wired up. 2 leds for each side and 4 behind the speaker in the middle. So, more than I originally planned but should look cool. I added a dimmer for each. I'll post some pics when it is all put back together.

I was going to suggest measure the resistance when you're satisfied the brightness is correct and change the potentiometer for a fixed resistor BUT as far as I can see from the diagram you've made it more complicated than it need be by wiring the pots as a split voltage tap across the potentiometer rather than just using the centre and the rh terminal as a variable resistor in series with the led rather than a potentiometer.

 

[ScottCash]

I was going to suggest measure the resistance when you're satisfied the brightness is correct and change the potentiometer for a fixed resistor BUT as far as I can see from the diagram you've made it more complicated than it need be by wiring the pots as a split voltage tap across the potentiometer rather than just using the centre and the rh terminal as a variable resistor in series with the led rather than a potentiometer.

Someone said in an earlier post that I had to run in parallel rather than in series because the PS was constant voltage instead of constant current.

 

[w0z]

Someone said in an earlier post that I had to run in parallel rather than in series because the PS was constant voltage instead of constant

Parwallel is fine, originally i thought you said 9V which is why I suggested series as up to 4 or 5 in series at 9v with a series resistor would have worked with LEDs which had no series resistor integral with the led, but now I see the supply is 5V and the LEDs have series resistors already so run the LEDs in parallel.
That has nothing to do with my comment about the potentiometers, So parallel the lamps and put them in series with 2 of the potentiometers terminals, then when you’ve set the pot. To the satisfied brightness, disconnect the LEDs and measure the resistance across the 2 terminals of the potentiometer, and replace pot. With a fixed resistor of the nearest preferred value. Is that any clearer?

 

[ScottCash]

Parwallel is fine, originally i thought you said 9V which is why I suggested series as up to 4 or 5 in series at 9v with a series resistor would have worked with LEDs which had no series resistor integral with the led, but now I see the supply is 5V and the LEDs have series resistors already so run the LEDs in parallel.
That has nothing to do with my comment about the potentiometers, So parallel the lamps and put them in series with 2 of the potentiometers terminals, then when you’ve set the pot. To the satisfied brightness, disconnect the LEDs and measure the resistance across the 2 terminals of the potentiometer, and replace pot. With a fixed resistor of the nearest preferred value. Is that any clearer?

Gotcha. Yes. Thanks!

 

[ScottCash]

Hi all. I am trying to figure out how to add a few amber color LEDs to a 1953 Zenith K622 radio. One to light the tuner, one for the clock and one behind the center grill. I've gone down some rabbit holes. At this point, I would tap the original 110vpower and connect an 110v AC to 9v DC step down power converter then, from that, parallel wire three LEDs after three resistors. Does this sound right???

Welp, after much learning....this is how it ended up looking. Thanks for all the help fellas.

 

[pirate]

That's a lovely radio!
I love things that glow!
I have a 6 tube nixie clock and it's just amazing with so many parameters you can adjust. I bought it for my daughter but she didn't like it so I took it back...every cloud!