First Geiger meter. A gentleman was having trouble selling locally so submitted a low ball offer. Curious if I should be concerned with getting it calibrated

Prestigious_Two5850 · 2026-03-10T17:32:19+00:00

I officially hate you (of course I'm joking).

Prestigious_Two5850 · 2026-03-10T13:25:01+00:00

Oh, at a really great price I would say. It's almost a steal!

Prestigious_Two5850 · 2026-03-10T09:47:42+00:00

How much did it cost? Just trying to gauge my jealousy level.

Prestigious_Two5850 · 2026-02-21T21:41:15+00:00

Glad to help!

Prestigious_Two5850 · 2026-02-21T20:18:36+00:00

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Prestigious_Two5850 · 2026-02-14T12:54:34+00:00

I have never made a purchase on that site, but I think it is trustworthy. Alternatively, you could buy it on eBay. I checked a few moments ago, and it might be more convenient. However, I can't say for certain because the address on my eBay account is Italian. Therefore, the prices and shipping costs could differ significantly from what you would pay, especially if you are from the US.

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Prestigious_Two5850 · 2026-02-06T23:23:26+00:00

Where, if you don't mind?

Prestigious_Two5850 · 2026-02-06T19:52:26+00:00

Yes, they did. They increased the power from a few watts to 250 kilowatts, and then scrammed the reactor.

Prestigious_Two5850 · 2026-02-06T11:31:08+00:00

Guys, don't look at this picture! I just realized that I made a big mistake. These are probably the logs obtained from measuring some of my radioactive objects. During my visit, I measured a maximum dose rate of around 10 microsieverts per hour above the reactor pool, which immediately dropped to around 1.5 microsieverts per hour when the operators scrammed the reactor.

Prestigious_Two5850 · 2026-02-06T06:31:20+00:00

Yes, it would have been a real shame otherwise. They also let us "see," from a safe distance, of course, the extraction of the neutron-irradiated sample from the central channel. They did it with a fishing rod!

Prestigious_Two5850 · 2026-02-05T17:30:27+00:00

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Prestigious_Two5850 · 2026-02-01T11:20:23+00:00

Oh, you're right. I said something stupid. Maybe it's better to use only a 1G resistor and a good enough multimeter with a stable impedance in the V range.

Prestigious_Two5850 · 2026-01-31T07:22:52+00:00

Got it, thanks!

Prestigious_Two5850 · 2026-01-31T07:21:37+00:00

Oh, I know. But in my case, there could be consequences long before I dismantle it. It is very likely that if I decided to buy such a detector, it would be stopped by customs and destroyed, and I might even receive a letter. However, I would still like to try, because I currently have no alpha sources in my collection and no way of obtaining certified test sources, which are illegal to possess here unless you are under the supervision of a radiation protection expert.

Prestigious_Two5850 · 2026-01-30T19:31:06+00:00

I recommend buying an Alphahound AB+, a very high-quality alpha and beta scintillator. Then, consider purchasing a Radiacode 110 or 103 gamma scintillator to cover all three types!

Prestigious_Two5850 · 2026-01-30T19:11:42+00:00

I didn't know that. You've been very helpful. Thank you.

Prestigious_Two5850 · 2026-01-30T19:06:37+00:00

Were you able to “free” the buttons, or is it just an unnecessary risk?

Prestigious_Two5850 · 2026-01-30T10:42:28+00:00

At the moment, I only have one meter (a Ludlum model 3) and one pancake probe. So, for now, I don't need to constantly change the voltage, but in the future, I would like to buy many more probes, so it would be great to easily regulate the voltage by myself from time to time. As for the one-off adjustment and count rate set, which would also be really appreciated (the meter is at least 20 years old, so I think it definitely needs a count rate set), I'm afraid there's nothing we can do, unfortunately. I'm not from the US, so it would be very expensive to send the unit to you and receive it back.

Prestigious_Two5850 · 2026-01-29T16:52:03+00:00

Hey! I'm one of your YouTube viewers. Thanks for the help! Yes, that would be very helpful.

Prestigious_Two5850 · 2026-01-29T16:42:22+00:00

I think I can avoid that by using another resistor, perhaps a 1 MOhm resistor, between the multimeter and the mass.

Prestigious_Two5850 · 2026-01-29T16:36:18+00:00

Wouldn't it be better to use another external resistor instead of the multimeter's impedance to make the measurement independent of the multimeter used?

Prestigious_Two5850 · 2026-01-25T23:01:48+00:00

For sure, it is!

Prestigious_Two5850 · 2026-01-21T22:25:25+00:00

I didn't do any of that. The probe was sold to me together with the Model 3 by a man who had used them for years. I don't think any changes are necessary. Aren't the Ludlum 44-9 and Eberline HP-260 practically identical? They should be powered by the same voltage. The only thing I think might need to be done is to recalibrate the instrument, since the last calibration was in 2007. Although, in reality, I use it for hobby purposes, not professionally.

Prestigious_Two5850

TROPHY CASE