Test Equipment Anonymous

Back in 2020 I converted the Type 310A Fan Mount from an extremely noisy AC powered fan to a quieter 12VDC fan with a supporting LM317T supply to allow speed adjustment. The conversion worked well but I still found the fan noise to be annoying. Today I replaced the original 12VDC fan with one claiming to be about 20db noise level.



The old fan has been removed and new fan installed. Set it to 12VDC. It is indeed whisper quiet and most likely less efficient but the fan mount was an option to the scope. The scope was originally designed to operate without a fan but the cabinet became uncomfortably warm. I suspect Tek offered this fan mount because of concerns from users. So even with less efficiency it should be more than adequate.


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And indeed it does provide adequate cooling. After being on for over an hour the cabinet is warm to the touch. No where near the high temperature without a fan. This is an all vacuum tube scope crammed into a small package so of course there will be some heat. This new fan is a win.

Fans can so annoying at times, but often they so essential that over the years I have learnt to largely ignore any noise from them unless they are shriekingly noisy.

I always sleep with a 20 inch box fan. Necessary when you work at night and sleep during the day. But I'm addicted to the soothing sound so I continue to use it. The large metal fans in the Tek 500 series scopes are somewhat loud but it doesn't bother me. Fans under 120mm drive me nuts if they are loud. The absolute worst are the hp counter fans.

MED6753 wrote: ↑Wed Jan 04, 2023 6:09 pm I always sleep with a 20 inch box fan. Necessary when you work at night and sleep during the day. But I'm addicted to the soothing sound so I continue to use it. The large metal fans in the Tek 500 series scopes are somewhat loud but it doesn't bother me. Fans under 120mm drive me nuts if they are loud. The absolute worst are the hp counter fans.

Yeah, the noise of those box fans is pretty close to white noise I think. My son plays white noise on his phone all night to help him sleep.

Has your box fan got a rotating grill to make the air swirl around the room? Mine has and the motor that drives it can at times make more noise than the fan itself does but on a hot night it is really important to have that going so that SWMBO gets some cooling air as well.

No, it's a fixed fan. No rotation side to side.

Interesting. I have a few old bits of kit that have fans with separate circuitry to drive them. I've always had the impression that they are more powerful than modern computer case fans and their form factor would make them hard to replace. However, a lot of work has been done on case fans and maybe they have become more efficient. I can just about hear the case fans in my computers, but they are temperature controlled. Case fans in modern instruments are a lot more noisy than the ones in computers.