How many engineers to change a light bulb?

Tektronix changed over to incandescent bulbs from Neon bulbs in some equipment in the early 1980s. One of the plug-ins for my 5223 was quite difficult (impossible) to read -- and one of the incandescent bulbs had failed -- seems to have fried its legs off. Oh, they're wired in series which means that none could be read. Darned if I didn't have the correct LED, but a grommet and another series resistor always helps. Further suggestions are welcome.

[IMGDEAD]http://www.tech-diy.com/TestEquipment/Tracers/5CT1N/DS150_Bulb.gif[/IMGDEAD]

[IMGDEAD]http://www.tech-diy.com/TestEquipment/Tracers/5CT1N/LED_Substitute.jpg[/IMGDEAD]
 
There is a Tek forum here:

TekScopes : All about classic Tektronix CRT o'scopes

Careful though these guys will consider replacing bulbs with LEDs a sin.

I think LEDs is the way to go though:)

How many are gone? If its only one and a few are in series then either short the dead one out if your brave, or add a resistor, maybe 10-50R.

Measure the voltage and current for the whole string. If you used a resistor factor it in to your normal Ohms Law calculation to work out the voltage and current of one bulb (or use it for your current measurement;))

Alternatively:-0 rip am all out. measure the open circuit voltage for the string and work on 20-30mA for a string of LEDs. Work your series R accordingly. This current may be a bit much for modern LEDs but its something to work from.

Tek stuff is the best:)

Cheers Matt.
 
It'll take 8 engineers or one good tech.
pick one to match yer budget and/or schedule.

Quoted for truth--the hoops and bullcrap I'm going through school to become an engineer and it's just so much different from when I went through school to become a technologist--we're not talking a long time between the two, either; I got my diploma and the following fall I began my degree program.

Grr... in college they gave us the tools and said 'solve this physical problem, now this one, now this one,' and it would get you thinking! But in university they expect you to derive the tools, then they give you numbers to put into your tools... but then no one knows what to do with them when they want to apply their shiny new tools on an actual problem. So since I was a "peer leader" (a teaching assistant, basically) in college I can't help but try to help my friends by filling in the gaps in their knowledge base of how to apply things to real-world situations problems!

But I'm a mechanical guy and can't really offer anything useful to this thread :(


/rant :rolleyes:
 
Quoted for truth--the hoops and bullcrap I'm going through school to become an engineer and it's just so much different from when I went through school to become a technologist--we're not talking a long time between the two, either; I got my diploma and the following fall I began my degree program.

Grr... in college they gave us the tools and said 'solve this physical problem, now this one, now this one,' and it would get you thinking! But in university they expect you to derive the tools, then they give you numbers to put into your tools... but then no one knows what to do with them when they want to apply their shiny new tools on an actual problem. So since I was a "peer leader" (a teaching assistant, basically) in college I can't help but try to help my friends by filling in the gaps in their knowledge base of how to apply things to real-world situations problems!

But I'm a mechanical guy and can't really offer anything useful to this thread :(


/rant :rolleyes:
Hello,
First off here in California the lamp has to want to change its self. If not for being color blind I would be an EE. Mechanical is my game. Talk about variable frequency drives (motor speed controller) there are IGBT’s in there as big as your arm. Building automation / mechanical system controls kinda blur into the electrical realm. We specify the motors, VFD’s and controls. Sparky does the lights and switch gear.
DT
All just for fun!
 
Fixed
 

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Above a certain serial number Tektronix changed to incandescent bulbs in series (was neons in parallel). These run off the -30V rail with a small silicon rectifier and an 820 ohm resistor. I put a 2.2K in series and a pair of white LEDs. The 5223 scopes are actually quite nice. This one came from a medical equipment company and was in almost new shape, and the cost was very low. Folks don't like them as the bandwidth is quite low. The 5223's have XY Plotter and pen-lift output on the backside, so you can take the output and dump it into a data acquisition card (you can see a couple of McDAC's on top of the scope.)