CFLs, both self-ballasted and externally-ballasted varieties, are still widely available in the United States. You can run down to Home Depot or Lowe’s and pick them up.

T10 was a fairly recognized alternative to T12. There were a number of triphosphor F40T10 fluorescent lamps available years ago were offered as a high brightness replacement for the F40T12. There may even be some models still under manufacture today. These T10 lamps are pretty rare in the wild, but they are not hard to purchase.

There was also an F20T10. This lamp is pretty rare compared to the F40T10. Lights of America used to include them with some of their fixtures.

@bulb_tester2009, I've had quite a few incidents involving electronic ballasted EOL's, most of which were CFL's, but some of which were desk lamps and
fixtures. Most of my incidents were my doing, since I would try my best to force a lamp to reach EOL... on magnetic Preheat, and on various types of
electronic ballasted CFL's and desk lamps. (Didn't have access to magnetic Rapid Start ballasted fixtures back then.)
I'll have to tell those stories another time.
I did have a somewhat similar situation occur one day, back in 2016, while me and a friend were playing video games in her bedroom.
She had a two lamp Incandescent light fixture in her bedroom. One lamp was incandescent, but the other was actually a rather large CFL... I think possibly
a 26w GE Helical, but I'm not sure. It was in a closed fixture... not really the best place for that size CFL.
Anyways, while we were playing Call of Duty, the CFL got dimmer and dimmer, then went out. The lens of the fixture was too frosted, so I couldn't see
any signs of orange flashing or swirling or anything like that. About five minutes later, there was a loud electrical *POP brrzzt* from the CFL.
It was very violent. The Incandescent lamp actually flickered when this happened, and I honestly don't know why. I remember jumping, and she jumped as
well and mumbled "what the *fffff* was that?" Then I let her know that the CFL just finished burning out.
Up to this day I still don't know why that Incandescent lamp flickered when the CFL popped, but I will say that, it was actually one of the most violent
CFL EOL's I've ever encountered.

T10 fluorescent lamps exist (1.25" diameter). Perhaps the most common use that I have seen is in 40W 48T10 germicidal tubes with pretty much identical specs to 40W 48T12. Not sure why they feel the need to reduce the diameter, but whatever. I think I saw here that some 48T10 Japanese energy saving lamps were also made.

Why was T10 not used more? It is a very interesting size, I don't think I would be able to identify it in the wild. Anybody have some T10 examples they would like to share?

When I was in primary school, the classroom used eight 36W T8 fixtures with poor-quality electronic ballasts. Among them, five brackets have Philips 54 tubes from 2003, one bracket has the new Philips 54-765 tubes, and two brackets have Osram LUMILUX 36W 865 tubes. One day during class, one of the heavily used Philips 54 tubes suddenly EOL, showing no flickering and other abnormal situation before going out. After about ten minutes, a huge cracking sound came from the fixture, as if a firecracker had been lit in the classroom, which scared all the students. The next day, the EOL tube was replaced by Osram 36W/865, but the fixture that made the cracking sound still didn't light up even when the new tube was installed. So the electrician disassembled the fixture, took out the old ballast that had exploded under EOL tube conditions and replaced it with a Philips EB-C ballast. After replacing the ballast, the new tube lit up and everything had back to normal.

A few years ago, when I left my junior high school (which was in the same campus as my primary school but not in the same building), some classrooms were renovated and many old fluorescent lamp fixtures were removed and piled up near the trash cans. So one day, I took off an Osram 36W/865 and a 2003 Philips 36W/54 from one of the fixtures and brought them home. During the moving process, a teacher noticed my actions and shocked

I used the iPhone 11 I got from my mother in 2022 and the Honor Magic 5 bought in 2023 before. Due to the poor shooting effect of the Honor Magic 5 (including but not limited to sharpening, smeage, and excessive AI repair marks), I got an iPhone 17 Pro silver with 1TB storage capacity(to store a large number of my videos) when the iPhone 17 series was released last September.
Here is my smart phone list:
2017  Redmi 4A
2018  Honor 8X
2021  Honor 30
2022  iPhone 11 and Honor 30
2023  Honor Magic 5 and iPhone 11
2025  iPhone 17 Pro (Honor Magic 5 and iPhone 11 as backups)

iPhone 11, iPad Air 4th generation for daily shooting and Honor Magic5 for shooting street lights and outdoor lighting.

I have replaced all the devices. Now I'm using the new iPhone 17 Pro and Sony Alpha 9M2 to take both photos and videos(Sony for HID run-up tests and iPhone for other videos). Since my camera is also used to take pictures of trains, I chose one that has a faster shutter speed and a relatively lower price.

Switzerland is banning all HID lamps after February 2027. The national ChemRVV directive concerning the Mercury content in lamps is not going to be extended after that date. That means all imports of HID lamps will be ceased.

Ok, now I have reached pure anxiety!

Last month, Philips and its CFLi OEM, Yankon Lighting, stopped producing CFLi at the same time. China Customs also issued an announcement stating that the import and export of such products will be prohibited in 2026. As the existing stock depleting, it will become increasingly difficult to buy CFLs with built-in circuits from well-known brands domestically or from foreign countries. Apart from China, Japan and several other nearby countries have announced similar production halt regulations. I’m not sure which countries still sell them currently.

I want to tap the output of the chip directly, triggering the relay through a MOSFET to avoid overloading the IC.

Depends what exactly the chip outputs, it may not be possible to tap it directly.
The chip may be a clone of the common LM8560 (as it was extremely popular and many clones under various names were made over the nearly half century since it was introduced), but also may be something completely different.
So we really need the circuit around the alarm output/control.

Also take into consideration, most clock radios do not have any real buzzer, but use the audio amplifier section of the radio for that function, that is why I asked also for the part controlling the power for the radio.


In an example of a very common circuit used with the LM8560 we would be looking for the D14, R16(?), C22 and Q3 - these are responsible for switching power to the radio. And also here the "buzzer" function goes via the radio chip by injecting the AL_OUT signal into the power amplifier input via C37 and R29.
Something similar I would also expect in your device, so you need to redraw the related circuitry...