What is inside an LED "starter"

I think I've answered my own question - they're perhaps for those cheap s*it single ended LED tubes, which take the power from the two pins at one end, thus requiring the power to go through the starter to run the LEDs. Double ended LED tubes make much more sense, they only draw current through the ballast, and you can just remove the starter, or leave it in wasting power as it'll be on all the time.

Or put in a dummy to look right but it is in fact just a cover with nothing inside. Brian

If it's an LED tube that takes live and neutral from one end, then the starter needs to be a short, not open circuit.

Ahh. What is your preferred desoldering method? Have you used any of the new SMP quikchip stuff yet?

Double-ended tubes are for morons who think their toaster needs two cords.

Think back to how fluorescents worked. Double ended LED tubes are to fit in those fittings without much modification.

Here's the way it is. There are 2 full wave rectifiers. The DC outputs are connected together; + of each and - of each. These feed the converter which is the standard chip, pulsing a transformer. The output of this is 1/2 wave rectified, filtered and goes to the string of LEDs. Now back to the 2 full wave rectifiers (FWR). One input to the 1st FWR comes from a pin on one end of the tube and the other input to the 1st FWR comes a pin on the other end. The 2nd FWR is wired the same way, except it uses the unused pins on the ends of the tube. For some reason there is a 5 ohm resistor in 3 of the 4 inputs to the FWRs. The 4th is direct connected. But if you trace is out, you can supply 120 VAC to any 2 pins and it works. You can even power from one end and short the pins on the other end and it still works. Clever!

The resistors are to limit the inrush current when initially charging the completely discharged capacitor at switch-on.

It's gotta be at least 20 years since I've even SEEN a flourescent lamp with a starter - are you guys all living/working back in the fifties??? Even the "high density" lighting in the shop 35 years ago didn't have starters any more -

Or perhaps we are talking about Euro/Oz stuff that runs on 240 VAC where starters are still common?

Actually, you have to look at my original post in this thread ... maybe I hijacked the original thread, but here it is:

BTW, my question about the resistors were "why have resistors on only 3 of leads, rather than on all four?"

And I seem to remember some that work on any supply voltage from 120V to

Did anyone need to run a TV on DC, or was it just to save having a heavy mains transformer?

There were certainly AC/DC *radios* that would cope with 120V to 250V or so. Needed a whopping great dropper resistor when working on the higher voltages. I used to have such a (portable valve) radio which would work on battery as well. The dropper was originally in the mains lead but had been replaced with a component in the case.

He's a pom.

We had DC at home in the late 1950s/early 1960s in our part of Brighton. The town wasn't completely changed over until 1965.

I remember my Tri-Ang train set suddenly acquired two small red boxes - transformers! Before that I had a rotary converter to get 12 volts.

There's still a lot of AC/DC people in Brighton.

Bill

ROTFL

'still' (if you accept that) is probably wrong. That only happened in recent years. And it's much more that *parts* of Brighton are heavily LGBTQ. Other parts are very little LGBTQ, probably below the average.

As I said I ain't a pro. I probably get my soldering iron out 5 times a year to repair something. I have changed an ethernet port on a laptop that my neighbour rather clumsily forced a USB plug into.

That reminds me of the advice I was offered some forty years ago not to bend down to pick up a 50 pence piece off the pavement if you were in New Brighton but to kick it along the pavement until you were outside of the town.