Yes. In my case, my tester is very compact, and is fitted with 2 bulbs for ability to switch from 1 to 2 current levels. The bulbs are inset into a recessed box I made to fit in a 3" x 3" opening. These small halogen bulbs are very handy.
Look for a brooder or heat (IR) lamp, they are not banned. Standard sizes are 175,250W available on line and in farm supply depots.
Sorry but that is not an equivalent.
A tungsten wire inside a lightbulb will take any voltage from zero to full Mains across it and go the full range from cold resistance (very low) to bright white hot resistance (highest, big time, a lot higher than cold resistance) for a full PTC almost constant current behaviour.
A large nichrome wire power resistor will NOT do that, not even close, simply because it will never ever get white hot.
And IF it does, it will either blow like a fuse or oxidize and burn in minutes, it is exposed to free air after all.
And in no case it will exhibit the 6:1 or higher resistance variation a humble lightbulb can easily do.
That extreme PTC behaviour is its main purpose, the "light indication" is just a bonus.
There is reason lightbulbs are used and not, say, pressing irons or toasters or fixed resistors.
Just asking: are pencil quartz-halogen lamps also banned?
What about dark red glass infrared/heating lamps?
PAR stage lighting?
Fridge lamps?
If car/truck incandescent lamps are still available, 5x24V ones in series will be good at 120V mains.
Are 32V lamps still available?
They were popular in wind power or static "Lister/Winco engine" rural electric systems.
Quite old school buy maybe .....
We are being forced to think outside the cage 🙁
In any case, if any supplier is found, it will be good to buy a lot to stash.
Call it cheap insurance and peace of mind 🙂
I guess they will work like some kind of Zener or something, in no case exhibit the very nonlinear effect of a cold-to-white-hot tungsten-filament-in-vacuum shows.
Besides that, actual current/power handling is minuscule, say 6-12W range, even if "equivalent" to 40-60W lamps.
That said, some enlightened mind MIGHT decide to build a "black box" which acts equivalent to, say, a 60W filament bulb.
Technically very doable ... any takers? 😎
the PAR lamp sizing (36 54 64) was originally intended for airfield landing lighting. PAR64 became the standard concert lighting bulb, the 120V version was more robust than the 230V version, so they were wired in series for a dimmer channel. PAR36 was a popular downlight narrow beam spot. that was in the 70ties.
I was going to say just connect up another amplifier or receiver in series with it. If that one comes on as if it were plugged straight in and the one you're testing doesnt ;')
I am surprised that you would ask this ? I have opened a number of them up, usually a smt offline bridge rectifier, hold up ecap, switch mode operation, nothing resembling anything analog 🙂
The magic ingredient is a white hot tungsten wire, strongly showing its PTC behaviour because if the extreme temperature it can reach.
No white hot (under full load) tungsten wire, no cigar.
And it survives only because it is held in vacuum (or with traces of some neutral gas, definitely not Oxygen).
To boot, it is designed for Mains voltage.
And very cheap ... what's not to like? 🙂
No white hot (under full load) tungsten wire, no cigar.
And it survives only because it is held in vacuum (or with traces of some neutral gas, definitely not Oxygen).
To boot, it is designed for Mains voltage.
And very cheap ... what's not to like? 🙂
Its not universal AC or regulatory approved or emit EMI like almost everything else does these days. 🙂
Or in other words, we might as well use a PTC, with just some simple additional electronics to do the same as a light bulb?
I have never used this light bulb method btw when fixing amplifiers.
I use just a automatic fuse (or multiple stages), in combination with an analog current meter en a voltage meter.
When turning any amplifier or old radio up with a VARIAC, you will see quickly enough if that meters goes to high.
At the same time keep track of the secondary voltage and you have enough information.
Just the light bulb information doesn't give much of information, how far and fast that analog current meter reaches, tells me a lot more.
I used to work on 500-2000W Class-AB PA amplifiers.
Light bulbs are not gonna help there.
I personally would also never rely on just one method and than try to get the last remaining stock out of anxiety.
I would much rather spend time and effort in something that's more sustainable for the future.
There are plenty of alternatives.
But yeah, I do get the frustration about something that just works and all of a sudden has to be replaced.
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Sometimes I think we’re so technical and practical around here that we miss the point. In the near future people new to this hobby will have an increasingly difficult time sourcing bulbs for a basic and useful tool. To talk about how useful or basic it is or the fact that the sky has not completely fallen yet does not solve the issue
I don't understand the ban anymore. For what has become a very short time, the price of led lamps was too high to force rapid adoption. Now they are approaching the same price, and because of the limited production of filament bulbs and improved reliability and light quality of led lamps, it's now the choice of whether you Need the particular qualities of a filament bulb, not excluding the energy dissipating properties. Shut it off now, people are smart enough to know what they're buying, and the effects on their power bill?
I'm more worried about maintaining a supply for my bedroom lamps than the dim bulb tester. Maybe they've got some well spectrumed LEDs at reasonable prices these days, I haven't looked in a while. I've yet to use a white LED bulb with an acceptable spectrum for pre-sleep (of course they're great for wake time lighting). And CFLs emit disgusting light and are an environmental nightmare (I threw a vacuum away a couple years ago after sucking up the remains of a dead CFL that my kid knocked off the counter during replacement--an impressively multilayered strike to the environment).
never used the "dim bulb tester" on the output. I ether used a dummy load with an ac current meter or sacrificial speakers I get from the thrift store.
On the power supply side, I don't need one because I look how the caps charge up on the variac ammeter as I apply voltage.
What people might find interesting, is that they purposely made incandescent light bulbs unreliable so they could continuously have a demand for them. The poor soldering techniques and materials make the LED bulbs unreliable. I have some success fixing LED bulb because I find most of the time, its bad solder. I noticed most lead free solder will cold solder joint inside a light bulb, and the stuff that doesn't is expensive ( silver solder at around $100/lb)