Philips PM2400 multimeter - UK Vintage Radio Repair and Restoration Discussion Forum

AV Radio · 8th Jul 2018, 12:27 pm

I have acquired a Philips PM2400 multimeter, which doesn't work.
The meter movement appears okay as it does move on some settings.
I have the circuit diagram for it. Does anyone have some experience with repairing one? Do the germanium transistors pack up with age? Any help would be great - especially an operator manual or service manual..

orbanp1 · 9th Jul 2018, 2:42 pm

Hi AV Radio,

I would start by cleaning the switches!

If I am correct, those Ge AFY transistors are industrial grade transistors, though I could be wrong - I am sure someone will correct me, if they know it better.

If you suspect those Ge transistors (do check the voltages on them), do take them out and measure them.
Do measure the leakage current (Ice0) and the beta.
Do use an old "school transistor tester" or a DMM with a h21 measuring capability, the "eBay transistor testers" seem to have some difficulty measuring Ge transistors, there was a thread on it here not that long ago.
An alternative is that you make up your own transistor measurements.

I have the schematics from the RM site, which is quite low quality. If you have a better quality schematics, please do share it!

I doubt that there is anything more on that meter than that is available on the RM site, but eBay lists a manual on a CD.

Good luck, Peter

8th Jul 2018, 12:27 pm	#1
AV Radio Diode Join Date: May 2016 Location: Pietermaritzburg, South Africa Posts: 2	Philips PM2400 multimeter I have acquired a Philips PM2400 multimeter, which doesn't work. The meter movement appears okay as it does move on some settings. I have the circuit diagram for it. Does anyone have some experience with repairing one? Do the germanium transistors pack up with age? Any help would be great - especially an operator manual or service manual..

9th Jul 2018, 2:42 pm	#2
orbanp1 Heptode Join Date: Nov 2009 Location: London, Ontario, Canada Posts: 675	Re: Philips PM2400 multimeter Hi AV Radio, I would start by cleaning the switches! If I am correct, those Ge AFY transistors are industrial grade transistors, though I could be wrong - I am sure someone will correct me, if they know it better. If you suspect those Ge transistors (do check the voltages on them), do take them out and measure them. Do measure the leakage current (Ice0) and the beta. Do use an old "school transistor tester" or a DMM with a h21 measuring capability, the "eBay transistor testers" seem to have some difficulty measuring Ge transistors, there was a thread on it here not that long ago. An alternative is that you make up your own transistor measurements. I have the schematics from the RM site, which is quite low quality. If you have a better quality schematics, please do share it! I doubt that there is anything more on that meter than that is available on the RM site, but eBay lists a manual on a CD. Good luck, Peter