It has a rather weird mechanical design.
Trademark of Philips :-)
That rotary switch looks to me like it's made by EBE. Series probably
EBE SB 20 F.
Trademark of Philips :-)
I see.
Not sure why they socketed the regulator. I mean how many times would it need to be taken apart? Why not just have the repair person unscrew it from the heat sink if need be and let it go with the main board?
Anyway - it back together and working. I looked at the schematic and found where to measure it's timebase signal, and it read 9,999,954 Hz, which of course is 46 Hz low, and this is consistant with the main reading of 10,000,04 which I got when measuring my 10 MHz OCXO. However it's now been adjusted.
All I need to do now is clean the outer case in warm soapy water to remove the nicotine and deal with the front panel. The front panel doesn't really stay on, and the only means of it ever staying on by design was the black sticky whatever-it-is stuff you see in the pic. Well, that stuff is no good anymore. What I might do is just take it all off and replace with strategically placed double sided tape. I don't want to leave a bunch of old black smoke-laden stuff stuck to the back like that.
Worked on getting the "black stuff" off the back of the panel today. It was not fun. It was some kind of black paper - not foam tape. Almost like a kind of tar paper. It was awful. I used goo gone and a razor blade. But I got it all off. I got it all cleaned up and then used some double sided tape to re-attach it.
Nice, I had 3 Philips Oscilloscopes, they all were super accurate, and probably were made in the 70's I think.
A PM3226 and a PM3217, both were super accurate scopes, loved the way they operated.
These ones were built when philips pretty much manufactured all the components inside, pretty much everything was labeled Philips in the PM3226, and it was made in India.
Putting it back together the sensitivity knob was very loose. I had lightly cleaned some corrosion of the shaft with 600 grit paper so I thought I made a mistake doing that, but it wasn't that. Again this is a part I've never come across. The knob actually was an adjustable fit sort of thing. The inner green part can be screwed in to a variety of positions, and the more you screw it in the harder it grips. No set screw.
That's a collet. Philips used them for most rotary knobs on their gear, they have a few advantages over simple set screws (no wearing down the shaft, excellent concentricity, no slipping), but are way more expensive. If you fumble off the brown knob cover there'll be a metric nut used to tighten it.
(Note: mechanical terms translated with dictionary, may or may not be the correct wors in English)
That's a collet. Philips used them for most rotary knobs on their gear, they have a few advantages over simple set screws (no wearing down the shaft, excellent concentricity, no slipping), but are way more expensive. If you fumble off the brown knob cover there'll be a metric nut used to tighten it.
But be careful with that brown cap on the knob -- the plastic can get very brittle with age. With the cap being in a very visible position, breaking it causes an annoying cosmetic blemish. I managed to do that on an old Philips function generator a while ago; still need to look whether any new knobs & caps with the same dimensions are still available ...
That's a collet. Philips used them for most rotary knobs on their gear, they have a few advantages over simple set screws (no wearing down the shaft, excellent concentricity, no slipping), but are way more expensive. If you fumble off the brown knob cover there'll be a metric nut used to tighten it.
Aha! Thanks - that's why I post pics of things I haven't seen before. Good info.
But be careful with that brown cap on the knob -- the plastic can get very brittle with age. With the cap being in a very visible position, breaking it causes an annoying cosmetic blemish. I managed to do that on an old Philips function generator a while ago; still need to look whether any new knobs & caps with the same dimensions are still available ...
Yes, I did attempt to push the cap off from inside but it indeed showed signs of starting to break so I chickened out. However I worked the tightening from the other end and it will be OK for now - it turns the switch OK without slipping.
After 20 odd years that cap and the knob will be pretty close to welded together. freezer spray or an overnight in the freezer, then try with a flat ended drift and it might pop loose. Otherwise gentle work around the join with a stanley knife blade will often loosen this grip.