Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => AmpTools/Tech Tips => Topic started by: Bieworm on December 19, 2020, 11:39:57 am
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Today I got some very old stuff for free. An old philips oscilloscope, a signal generator and some other generator that produces various signals. Is that stuff I can use to make amp diagnosis? I mean, the scope is the size of a small amp with that round screen. The signal generator us 1hz to 100khz. So that one I can really use.
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If it works, then it's up to the operator to "understand" the "if it can" part :icon_biggrin:
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If it works, then it's up to the operator to "understand" the "if it can" part :icon_biggrin:
Be nice Shooter.. I'm still in the learning process 🤪🤪
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What's the scope model number? Post a pic or two.
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Be nice Shooter
I am in real life, I have to keep buying new shirts :laugh:
you didn't state IF they worked, just you got old stuff.
for tube amps, any working scope will do just fine for 90% of the signal path/noise problems
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It's really old. There are tubes inside the scope !!!
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What's tha 3rd thing?
If I'm reeeeeeeal Lucky it's going to work. Probably need a scope to check these equipments. 😆😆😆
But I think its real cool stuff.. I mean, there's tubes in there 👍👍👍
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Manuals are available on the net. Hope you can read Dutch!
The third piece is for use on obsolete analog color TV. It's of no use in the present world.
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Uncles can be generous.very nice .Bieworm
I lucked out helping my freind ..Roger s uncle .to move
He gave me a 100w el34 amp .broken tube .u may know it ..the beer tube .
Scope.sound generator.as well.
Fuzz pedals ,old school tube tape loop mixes tube 4reel to reel .and more stuff .too much stuff.mic stands guitar stands .
My shed is full of unclestools and no room to walk.
I love uncles
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:laugh:
I thought you got government surplus when you said "uncle"
If the scope powers on and you have a narrow green line going horizontally you're golden.
Philips makes good stuff
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Manuals are available on the net. Hope you can read Dutch!
The third piece is for use on obsolete analog color TV. It's of no use in the present world.
Geen enkel probleem!!! (Noooo problem) that's my main language.. I'm from Belgium
Me thinks that stuff is real high end professional stuff, that was used in the Philips research labs in Eindhoven holland. 50 years ago or something like that. If broken should definitely be repairable
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that third item might be a treasure trove of parts you can use in other stuff. if it's not full of tubes might have some nice old transistors that could be used in fuzz pedals
obsolete test gear, old organs left by the side of the road... all contain fun stuff
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that third item might be a treasure trove of parts you can use in other stuff. if it's not full of tubes might have some nice old transistors that could be used in fuzz pedals
obsolete test gear, old organs left by the side of the road... all contain fun stuff
You're probably right, but tubes would be a real surprise.. there ain't no cooling vents on that device.
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That PM 5105 looks similar to my HP 204D...
(http://sluckeyamps.com/warbler/w_109.jpg)
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To track down oscillation in the amp I should feed a signal into it at the grid of the 1st triode, no?
What frequency should I start with? If I understand this correctly it should be above speaker max frequency range? So above 5kHz.. what do you suggest?
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To track down oscillation in the amp
start easy, use the scope to "look" for the oscillation. If you find it, knowing the frequency of it can help determine what's causing it.
since it's there already, adding a "new" signal with a seg-gen might get confusing
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that third item might be a treasure trove of parts you can use in other stuff.....
Not really. You could harvest dozens of transistors, some Ge, a couple 30W types. (I was however surprised that it IS transistors, not chips.) Frank has the manual:
https://tubedata.tubes.se/other/sos/Philips_PM5508_PAL-ColourPatternGenerator_OM.pdf
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that third item might be a treasure trove of parts you can use in other stuff.....
Not really. You could harvest dozens of transistors, some Ge, a couple 30W types. (I was however surprised that it IS transistors, not chips.) Frank has the manual:
https://tubedata.tubes.se/other/sos/Philips_PM5508_PAL-ColourPatternGenerator_OM.pdf
Better store it away then... who knows when the crops will come in handy some day
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EDIT -- most transistors are Silicon, nothing special. The power regulator has Ge. I would not be sure Frank's manual is 100.0% correct-- the high-profit low-volume box begs for running production changes as the transistor art advances and as trailing-edge types pile-up behind the factory.
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EDIT -- most transistors are Silicon, nothing special. The power regulator has Ge. I would not be sure Frank's manual is 100.0% correct-- the high-profit low-volume box begs for running production changes as the transistor art advances and as trailing-edge types pile-up behind the factory.
That scope OTOH contains real treasures might it be broken. Lots of Ge transistors and quite a few tubes. ECC88 (4 pcs)
Dude, that is (to me) real complex stuff put together...
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Is this a normal signal with the probe touching nothing? When I ground it to its ground clip it flattens out ...
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congrats! you have a working oscilloscope!
--pete
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Thx! This is new to me.. next hapter in amp building for me. A necessary and logic one
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Ideally it's flat with no probe connected.
but any green trace is a good start
find a signal source and test further.
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you have 1V calibration terminal (on the right of the LEVEL knob) - connect your probe to that you should see a square wave that spans 4 vertical divisions on the graticule.
move the TRIGG. source switch switch to YB (photos show probe connected to BEAM B).
move the TRIGG. mode switch to NORMAL
set TIME/Div to 20uS (rotate vernier - the red hash marked control fully clockwise) - should display 2 full cycles IF it's a 1KHz source.
set BEAM B to X1 (not X10) and V to .5V (rotate the vernier - the red hash marked control fully clockwise).
touch the probe to the CAL 1V terminal.
--pete
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you have 1V calibration terminal (on the right of the LEVEL knob) - connect your probe to that you should see a square wave that spans 4 vertical divisions on the graticule.
move the TRIGG. source switch switch to YB (photos show probe connected to BEAM B).
move the TRIGG. mode switch to NORMAL
set TIME/Div to 20uS (rotate vernier - the red hash marked control fully clockwise) - should display 2 full cycles IF it's a 1KHz source.
set BEAM B to X1 (not X10) and V to .5V (rotate the vernier - the red hash marked control fully clockwise).
touch the probe to the CAL 1V terminal.
--pete
Do I connect the signal generator to it to put in a 1kHz signal?
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touch the probe to the CAL 1V terminal.--pete
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Ideally it's flat with no probe connected.
Normally there is 50/60Hz on a no-connection probe if you turn-up enough.
Because it is capacitive coupling, the highs are enhanced, so the "sine" will be jaggy.