Hello to everyone!
I just acquired an old Scopex 4D10B oscilloscope for free, just to start doing some electronics diy works, like tube amps and preamps etc etc. It hasn't the cable that you use to make measurements (don't know the english word, sorry), but when you turn it on and wait for warmup, it doesn't show an horizontal flat line, like other scopes I've used, but a single dot, that sometimes extend itself into a small line, sometimes it moves randomly and slowly to the right...
No matter where i turn the knobs, I still have a single dot. I've followed the turn-on procedure in the manual, but nothing...
I've got the service manual with schematics and adjustment procedures, but I haven't found any info about it except for this eBay auction http://cgi.ebay.co.uk/SCOPEX-4D-10A...556718174QQcategoryZ45008QQrdZ1QQcmdZViewItem
that shows a very similar one (mine is black).
I've never worked on scopes, but I've already worked on tube and ss amps, and dealt with high voltages. Can someone help me?
I just acquired an old Scopex 4D10B oscilloscope for free, just to start doing some electronics diy works, like tube amps and preamps etc etc. It hasn't the cable that you use to make measurements (don't know the english word, sorry), but when you turn it on and wait for warmup, it doesn't show an horizontal flat line, like other scopes I've used, but a single dot, that sometimes extend itself into a small line, sometimes it moves randomly and slowly to the right...
No matter where i turn the knobs, I still have a single dot. I've followed the turn-on procedure in the manual, but nothing...
I've got the service manual with schematics and adjustment procedures, but I haven't found any info about it except for this eBay auction http://cgi.ebay.co.uk/SCOPEX-4D-10A...556718174QQcategoryZ45008QQrdZ1QQcmdZViewItem
that shows a very similar one (mine is black).
I've never worked on scopes, but I've already worked on tube and ss amps, and dealt with high voltages. Can someone help me?
Re: Re: My scope doesn't work - need help!
Thanks Hugo, I just forgot the word "probe"
So I'll open it and check for bad joints, since the other day i turned it on and it showed some kind of horizontal line
Sorry, what do you mean?
Netlist said:'Probe' is the name of the cable.
Re. your dot: I suspect a bad soldering in the horizontal amplifier stage. Or your time base could be in the xy position, but then the spot wouldn't move along the screen.
/Hugo
Thanks Hugo, I just forgot the word "probe"
So I'll open it and check for bad joints, since the other day i turned it on and it showed some kind of horizontal line
jacco vermeulen said:
Sorry, what do you mean?
HELP ME!!!
I've resoldered everything in the 'scope, but I can't get the horizontal line, only a single dot and strange behaviour.
I'll try to explain...
Every control does the supposed action to the dot, BUT the horizontal (position?) control only moves the dot very little, and when I turn the TIME/CM rotary switch, the dot moves to random positions on the screen, and sometimes creates a small horizontal line on the right of itself, and many times the line is changing, making itself smaller or longer... This 5 minutes ago: now I turn the aforementioned knob but now the dot doesn't move (except for the "x-y" position).
What can cause this? All other controls are in the 12 o'clock position, all pushbuttons off, nothing attacched to the various inputs (no probes).
Please! I need Help!!!
I've resoldered everything in the 'scope, but I can't get the horizontal line, only a single dot and strange behaviour.
I'll try to explain...
Every control does the supposed action to the dot, BUT the horizontal (position?) control only moves the dot very little, and when I turn the TIME/CM rotary switch, the dot moves to random positions on the screen, and sometimes creates a small horizontal line on the right of itself, and many times the line is changing, making itself smaller or longer... This 5 minutes ago: now I turn the aforementioned knob but now the dot doesn't move (except for the "x-y" position).
What can cause this? All other controls are in the 12 o'clock position, all pushbuttons off, nothing attacched to the various inputs (no probes).
Please! I need Help!!!
Hi Giaime,
Long time. I'm glad you got a 'scope.
No horizontal sweep. The horizontal amplifier isn't working, or you may have dirty switch contacts. I am not familiar with yours, but some have a switch on the back too.
Always check the power supply voltages first. Once you are sure that's okay, go further.
Can you send the schematic of the horizontal oscillator and amplifier circuits? That will give test points. Also the power supply for the same reason.
-Chris
Long time. I'm glad you got a 'scope.
No horizontal sweep. The horizontal amplifier isn't working, or you may have dirty switch contacts. I am not familiar with yours, but some have a switch on the back too.
Always check the power supply voltages first. Once you are sure that's okay, go further.
Can you send the schematic of the horizontal oscillator and amplifier circuits? That will give test points. Also the power supply for the same reason.
-Chris
Hi Chris! Yes, it's been a long time
I got this scope from a fellow at www.videohifi.com, a hi-fi oriented italian forum: we were talking about scopes and professional DMMs, they said that good entry level ones are going for peanuts, and I asked if someone could give me a scope really for peanuts because I couldn't find one... An experienced tech out there (his site http://www.sistecgps.com/ they make custom gps) sent me a full working professional DMM (Schlumberger Solartron 7050) and this scope FOR FREE! He even refused to accept the s/h money, he said it was for my birthday (22 october now I'm nineteen).
I found a dead capacitor in the 'scope, it is a 1000uF 40V, it is the first PSU filter cap for the +20 supply. It's leaking some strange green substance, even on the pcb other than from it's positive terminal. I guess it's bad in fact it measures dead open.
I think he is the culprit, but I also think that he's the only one, since after that cap there is a fully regulated supply. I will replace it and keep posting...
And no, I can't post a schematics, since it isn't avabile in the Net and I have it on paper, but I don't have access to a scanner right now...
Thanks to all!!!
I got this scope from a fellow at www.videohifi.com, a hi-fi oriented italian forum: we were talking about scopes and professional DMMs, they said that good entry level ones are going for peanuts, and I asked if someone could give me a scope really for peanuts
because I couldn't find one... An experienced tech out there (his site http://www.sistecgps.com/ they make custom gps) sent me a full working professional DMM (Schlumberger Solartron 7050) and this scope FOR FREE! He even refused to accept the s/h money, he said it was for my birthday (22 october now I'm nineteen).I found a dead capacitor in the 'scope, it is a 1000uF 40V, it is the first PSU filter cap for the +20 supply. It's leaking some strange green substance, even on the pcb other than from it's positive terminal. I guess it's bad
in fact it measures dead open.I think he is the culprit, but I also think that he's the only one, since after that cap there is a fully regulated supply. I will replace it and keep posting...
And no, I can't post a schematics, since it isn't avabile in the Net and I have it on paper, but I don't have access to a scanner right now...
Thanks to all!!!
Hi Giaime,
Make sure you get all the stuff cleaned off the board. Then do voltage checks. Beware to stay completely away from the focus / intensity controls. Hold a neon bulb near wires to check for really high voltage. Use insulated pliers & do not touch the wires!
Just may sure you are testing in the low voltage areas. I'd hate to see you blow up your "new" meter.
Congrats on your birthday present!!
You can email a picture of the schematic some time.
-Chris
Make sure you get all the stuff cleaned off the board. Then do voltage checks. Beware to stay completely away from the focus / intensity controls. Hold a neon bulb near wires to check for really high voltage. Use insulated pliers & do not touch the wires!
Just may sure you are testing in the low voltage areas. I'd hate to see you blow up your "new" meter.
Congrats on your birthday present!!
You can email a picture of the schematic some time.
-Chris
Oh I think that he has so much TV sets to be repaired that I cannot wait in the shop all day long for my scope
Anyway you convinced me, today I'll take the scope to him.
But... just for speaking
Could the open capacitor be the problem? I don't think so, because after it there was a voltage regulator, so the +20V supply would work, high ripple but would work. And the +20 does nothing to the horizontal output, which is powered by +/-200V rails.
And I've seen that the dot only moves to the right: so only one of the push-pull transistors in the horizontal amp doesn't work! But I suspect it might be just a bad solder joint, since IIRC the scope worked the first time, only the second time it showed the dot.
Thank you all for the help!
(sorry, but still no schema )
Anyway you convinced me, today I'll take the scope to him.
But... just for speaking
Could the open capacitor be the problem? I don't think so, because after it there was a voltage regulator, so the +20V supply would work, high ripple but would work. And the +20 does nothing to the horizontal output, which is powered by +/-200V rails.
And I've seen that the dot only moves to the right: so only one of the push-pull transistors in the horizontal amp doesn't work! But I suspect it might be just a bad solder joint, since IIRC the scope worked the first time, only the second time it showed the dot.
Thank you all for the help!
(sorry, but still no schema
)
Hi Giaime,
Sy got me thinking, and I believe he is right here. It would be too easy to contact the higher voltages. Just ask me, I've gotten shocks more repairing 'scopes than any other item.
Perhaps you can arrange to meet him (your tech) after hours or if he works on the weekend to "catch up". Offer him coffee and lunch, that's always worked for me in the past. I have helped younger fellas in the past and done a lot of teaching. It depends on how well you know him. Of course you need to pay him, but the teaching is very worth while. You may end up wit ha good friend and mentor.
Make a list of everything you have changed, another of everything you desoldered or checked. Just so he does not have to troubleshoot a small error you may have made. He'll thank you for it.
-Chris
Sy got me thinking, and I believe he is right here. It would be too easy to contact the higher voltages. Just ask me, I've gotten shocks more repairing 'scopes than any other item.
Perhaps you can arrange to meet him (your tech) after hours or if he works on the weekend to "catch up". Offer him coffee and lunch, that's always worked for me in the past. I have helped younger fellas in the past and done a lot of teaching.
It depends on how well you know him. Of course you need to pay him, but the teaching is very worth while. You may end up wit ha good friend and mentor.Make a list of everything you have changed, another of everything you desoldered or checked. Just so he does not have to troubleshoot a small error you may have made. He'll thank you for it.
-Chris
scopex oscilloscope 4d10b
i have a scopex oscilloscope 4d10b...?
it was my grandads before he sadly passed away and i was cleaning his house out when i came across it.
somebody has offerd to by it from me for £70 but im not to sure how much this bit of kit is worth.
also i know nothing about it...so any help on how much it is worth and what it is used for would be much appreciated
thanks
p.s It all lights up so i assume it is in working order
i have a scopex oscilloscope 4d10b...?
it was my grandads before he sadly passed away and i was cleaning his house out when i came across it.
somebody has offerd to by it from me for £70 but im not to sure how much this bit of kit is worth.
also i know nothing about it...so any help on how much it is worth and what it is used for would be much appreciated
thanks
p.s It all lights up so i assume it is in working order
yes i looked on ebay....and there is somebody selling the same model....the thing is i sent him a message asking for info and he dosent know a thing about it either..he is in the same boat as me.
he has his at £150 on ebay...i put mine on for £50.
but like i said someone has offerd me £70..(before bidding had even started)
he has his at £150 on ebay...i put mine on for £50.
but like i said someone has offerd me £70..(before bidding had even started)
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