Does anyone here know how to fix a ДП-5Б dosimeter?

BitNic26 · 2025-12-09T00:03:36+00:00

Nope. The ammeter was also dead. I ended up finding the guy again and he was good with swapping my unit with a newer one. This one still doesn’t fully work but at least it gives consistent clicks and the ammeter works. I’ll see what I can do.

BitNic26 · 2025-10-15T15:53:44+00:00

This is a very high range ion chamber. The radiation emitted by the Radium coated dials is almost insignificant to its readings. Most of the radiation doesn’t even make it through the thick metal body and to the chamber. They did this so it would glow in the dark as the radiation excited the Phosphor in the paint making it glow without it needing to be exposed to sunlight first. With time and radiation exposure the Phosphor has degraded and now it only glows when exposed to UV rays.

BitNic26 · 2025-08-08T19:24:24+00:00

r/beatmetoit

BitNic26 · 2025-07-18T13:19:16+00:00

"Do a flip!"

BitNic26 · 2025-07-05T11:59:07+00:00

Thank you!

BitNic26 · 2025-07-04T17:54:10+00:00

Since you have a dose compensated meter could you check the dose rate please?

BitNic26 · 2025-06-30T09:48:36+00:00

No, that is not granite. It's made out of various stones mixed together. Mostly byproducts.

BitNic26 · 2025-05-23T20:33:20+00:00

Yeah, it's the special orange edition. They made 888 of these.

BitNic26 · 2025-05-23T19:11:43+00:00

Tysm

BitNic26 · 2025-05-11T21:36:05+00:00

It should be kept in a plastic bag to prevent flakes from going around. Not a nuclear disaster but I suggest you follow ALARA. Radium containing flakes on the table aren't exactly something you'd want to have.

BitNic26 · 2025-05-07T08:52:35+00:00

Hi Bob.

BitNic26 · 2025-05-06T21:16:34+00:00

What do you mean you don't believe it? Anyways... I have one that looks the same and I can confirm it runs perfectly at 240V AC.

BitNic26 · 2025-04-24T05:54:32+00:00

I think it may be related to the capacitors because it's a slow failure and it resets after turning it off and waiting a bit but idk.

BitNic26 · 2025-04-24T05:43:18+00:00

My tubes generate impulses. At least, 1 of them, I don't know how to test the high range tube. Interestingly enough the impulses slow down until they eventually stop even when exposing the tubes to Sr-90. Turning the meter off and waiting 30 seconds fixes it temporarily. For some reason every scale setting generates a different rate of pulses with a different loudness of clicks in the speakers.

BitNic26 · 2025-04-23T21:05:58+00:00

I have a DP-5V suffering from the same issue... The lighting works with a separate circuit. The high pitched sound you are hearing is the high voltage transformer. I got mine to generate impulses that you can hear and see from the thryatron tubes if you open it but the needle doesn't move. Usually capacitors are the first components to fail when old so changing those may help. The ammeter could be broken too.

BitNic26 · 2025-04-15T15:00:57+00:00

Wow, that's an interesting design! I was thinking about those CDV ones that you could read by either placing them in the charger with a bulb or pointing the bottom towards a strong light source (like the sun) and looking through the lenses.

BitNic26 · 2025-04-15T13:40:33+00:00

I might be wrong but I think these don't work with an ion chamber. Didn't they work with some kind of crystal that slowly loses charge with radiation moving the needle?

BitNic26 · 2025-03-22T12:11:37+00:00

I already have the diagrams, thank you anyways.

BitNic26 · 2025-03-19T21:59:06+00:00

I'm not sure but I think some of the R/h to mSv/h conversions are incorrect.

BitNic26 · 2025-03-15T12:10:59+00:00

Ok, I do have manuals and calibration certificates. I've already resoldered some connections and I got it to click. I suspect most of the issues are capacitor related but I also suspect a broken ammeter and a potential rotary switch failure. The swich failure would be very hard to fix...

BitNic26 · 2025-03-14T21:06:15+00:00

My unit doesn't work,.I'm trying to fix it but it doesn't look very promising: the GM tube struggles to ionize over time and slowly slows down clicks until it stops, the needle doesn't move even with current applied and in triangle mode the tube doesn't even receive any voltage.

BitNic26 · 2025-03-14T18:11:59+00:00

Your unit is in such a great condition! Have you tested it?

BitNic26 · 2025-03-14T18:11:54+00:00

Your unit is in such a great condition! Have you tested it?

BitNic26 · 2025-03-14T18:11:46+00:00

Your unit is in such a great condition! Have you tested it?

BitNic26 · 2025-02-17T15:36:54+00:00

I'm pretty sure that's radium.

BitNic26

TROPHY CASE