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Philips PM3217 50MHz 2 channel CRO gutshots



I was bored today so I decided to take apart my oscilloscope and see what's inside. It's a 'scope I got about 3 years ago on eBay for around £70 working but without probes IIRC. I didn't see any photos around and I know how everyone loves gutshots, so I thought I'd post them.

The PM3217's a 50MHz 2 channel analog oscilloscope which has the interesting feature that as well as mains, you can power it from a battery (22-27V DC, 1.1A) - useful for situations which might otherwise need an isolation transformer.

The most recent date code I found is 17th week of 1983.

Vaguely interesting points (not all suprising, but interesting at least to me) are:
-All through hole construction.
-All discrete transistors! There are 6x 7400 series logic ICs and 5x NPN transistor arrays (2x CA3086, 3x SL3145), but other than that, it's all discrete bipolar transistors. Not even an opamp in sight.
-Quite a few flying wires soldered directly to the boards.
-The power supply is a push-pull coverter driven by bipolar transistors resonating at around 18kHz with minimal regulation. Rather than being supplied directly by the rectified mains though, this switching supply is supplied by a 24V secondary on a relatively heavy 50/60Hz mains transformer (or 24V battery). (I'm a bit of a power supply geek)
-Just the retro look of the thing :D.

I have a PDF service manual for it, but it's too big to attach here. I only got it from googling, so I'm sure you can find it if you want to see. It does have lots of info including schematics etc in it.

Hope someone else finds this interesting!

amazing. almost 99% of the componbents in that machine are made by philips themselves. i only spotted a few RCA and TI chips like 3 or  4.. and the pushbuttons switches were bought too.
 anything else. including transformers, connectors, made philips...

today ? philips doesnt make didly squat.. its all sold. how the big have fallen

The worst part: They kept up this policy of making most everything themselves for decades. Open a piece of Philips vacuum tube equipment from the fifties, and it is the same story all over again. Philips parts everywhere, up to and including the tubes themselves.

Yep,there were two ways of doing things---the Philips way,or the highway! ;D

I have one of these scopes. Pretty nice, alright, but the controls were HORRIBLY noisy and furthermore very difficult to clean. Maybe not as bad in this respect as a Tektronix but give me a Kenwood-built B&K for serviceability any day.

I will say that since cleaning the controls, they have stayed clean so far - about 2 years now.


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