Neon Lamps In Vintage Radio

Your point was?

OK the 4007 is 1,000 volts - hardly relevant under the circumstances.

That would be the logical thing to do.

Cheers! Rich

Are they in parallel? If so, it might be the case that they are in a series heater chain with the valves (and the parallel lamp bit is to stop the whole radio failing if one dial lamp blows). If it is a series heater/lamp chain in this way then the set is probably transformerless ("AC/DC") and VERY dangerous to work on or use without an isolating transformer (NOT an autotransformer. That is because the set will work even if the (two-pin) power connector is wrongly inserted, but the chassis and all the fittings will be live!

Oh, that changes everything. Ignore my last post! My other point is that historical radios are best not modified.

How can that be? The common T1.75 LED is much smaller than the typical pilot lamp. And LEDs come in much smaller packages than T1.75 if you need smaller ones. Surely there are LEDs that will fit in the same space as your old pilot lamps.

What size and shape (or part number) are your pilot lamps? Do you know the voltage applied to each lamp, and whether it's AC or DC? You'll need to know these things to select the LED biasing components. Guessing is not the preferred approach.

You might consider installing the LED into the base of the old pilot lamp, possibly with a small resistor and, if necessary, a diode too. This approach would let you keep the radio wiring all original and still enjoy the improved efficiency and life expectancy of LEDs.

A 220R resistor would be fine off 6 volts.

Ditto that last. If it is a thing of beauty keep it honest to its original form. You have to make the call there.

If you decide to use LEDs use them back to back for AC and to use two ordinary 20 milliamp leds use a 150 ohm 1/2 watt resistor in series with them. Leds are in parallel anode to cathode and served by a single 150-160 ohm resistor from the AC supply (if it is indeed AC - with a transistor set it might be DC)

I'm going to leave it as it is.

The pilot lamps are behind the dial reflecting off the clear plastic faceplate, and therefore aren't very effective, I was hoping to bring the LED's forward to illuminate the dial better, but the faceplate doesn't allow that.

No it's not the most beautiful radio I've ever seen, so I have no regrets about modifying it. It's yellowed plastic, with a clear faceplate. Quite ugly.

I see. I thought you had said that you wanted brighter light and longer life expectancy than you could get with incandescent lamps. LEDs would have done that nicely, and with lower power consumption too.

But replacing the original lamps is certainly the easiest thing to do. And I do agree that keeping it original, even if it's not a highly desirable collector's item, is always a good choice. Sometimes, the antique that shows its age is the most interesting one.

That's what a lot of vintage radio collectors say. The radio is staying original. I really don't fancy drilling holes in the faceplate.

Thanks for all your help, everyone, I will probably be back in the future, as I am just getting interested in electronics, and will likely need help with something or another.

I'm glad to hear that!