Test Equipment: Oscillocopes

[TinselKoala]

On testing the HV supply: Don't bother! This has to do with the display itself and that seems to be working just fine. If you didn't have a trace, or trace too dim,  or improper blanking or something like that, then that's the time to worry about the HV supply. It's just too tricky to mess with that unless you actually suspect some problem and I don't think you have any reason to suspect a problem in the HV circuitry at this point. 

Also, in regards to the calibration.... again... you are looking at "overkill" here. The equipment necessary to do a full and proper calibration is going to be expensive, and you'd be better off spending that money on something else that you'll use all the time. Who needs a time marker generator or a calibrator generator or a signal pick-off unit for anything, except a bench technician who spends all day every day calibrating old analog scopes? Plus you need another scope to do a full calibration anyway.
 
You can look for a good modern full-function Function Generator, and do most of the performance verification and much of the calibration checks with that. Plus your GenRad oscillator for higher frequencies. And a Variac is always handy around the lab. These, some patch cables, adapters and a 50 ohm terminator, are enough.

[MileHigh]

I found these chips:

http://www.analog.com/media/en/technical-documentation/data-sheets/AD9837.PDF
http://www.analog.com/en/products/rf-microwave/direct-digital-synthesis-modulators/ad9833.html#product-overview

Cheap:
http://www.digikey.ca/product-detail/en/AD9837ACPZ-RL7/AD9837ACPZ-RL7TR-ND/2677471

•Digitally Programmable Frequency and Phase
•12.65 mW Power Consumption at 3 V
•0 MHz to 12.5 MHz Output Frequency Range
•28-Bit Resolution (0.1 Hz @ 25 MHz Ref Clock)
•Sinusoidal/Triangular/Square Wave Outputs
•2.3 V to 5.5 V Power Supply
•No External Components Required
•3-Wire SPI Interface

Another virtual project in a box:  You buy a tiny Arduino board with a VGA out and a USB port for your mouse.  You run Linux for the GUI and write a small program to poke the registers of the oscillator chip.  With two small isolation transformers and three wall warts you can get a "floating set" of +5, -15, and +15 volts.  You buffer the output of the oscillator chip with an op-amp.   You have analog gain and offset knobs.  You have direct out and 50-ohm out.  You can even do the high-current transistor out if you want using a pair of external batteries as the power source.

A small box that you plug in the wall, and there are a few BNC panel-mount connectors on the box, and you use an old VGA monitor and mouse lying around.  You "cheat" and there is just a neatly wired breadboard inside the box along with the Arduino module.

I know I am so out of date, perhaps there is a module that does that all for you.  But then you miss out on the fun of making it!

[MarkE]

eBay has lots of function generators and kits built around DDS chips, some for under $20.  Pirate Bill asked about using one.  Complete and in a box you can buy one that does 5 MHz or 10 MHz for around $70.

[Brian516]

I found these chips:

http://www.analog.com/media/en/technical-documentation/data-sheets/AD9837.PDF
http://www.analog.com/en/products/rf-microwave/direct-digital-synthesis-modulators/ad9833.html#product-overview

Cheap:
http://www.digikey.ca/product-detail/en/AD9837ACPZ-RL7/AD9837ACPZ-RL7TR-ND/2677471

•Digitally Programmable Frequency and Phase
•12.65 mW Power Consumption at 3 V
•0 MHz to 12.5 MHz Output Frequency Range
•28-Bit Resolution (0.1 Hz @ 25 MHz Ref Clock)
•Sinusoidal/Triangular/Square Wave Outputs
•2.3 V to 5.5 V Power Supply
•No External Components Required
•3-Wire SPI Interface

Another virtual project in a box:  You buy a tiny Arduino board with a VGA out and a USB port for your mouse.  You run Linux for the GUI and write a small program to poke the registers of the oscillator chip.  With two small isolation transformers and three wall warts you can get a "floating set" of +5, -15, and +15 volts.  You buffer the output of the oscillator chip with an op-amp.   You have analog gain and offset knobs.  You have direct out and 50-ohm out.  You can even do the high-current transistor out if you want using a pair of external batteries as the power source.

A small box that you plug in the wall, and there are a few BNC panel-mount connectors on the box, and you use an old VGA monitor and mouse lying around.  You "cheat" and there is just a neatly wired breadboard inside the box along with the Arduino module.

I know I am so out of date, perhaps there is a module that does that all for you.  But then you miss out on the fun of making it!

Hells yeah, man!
That's pretty awesome you found that... I might just have to order a couple when I do place an order.  I know I could just buy a cheap Chinese $20 function gen,  but I need the experience learning how to design and build circuits, and learn how to write code for Arduino, so that would be a great project for me to get into. With the help of progs like ExpressPCB and SCH and a good simulator, and referencing schematics for function gens, I'm sure I could get it figured out.  Plus I have the Arduino - the Mega 2560, Yun, and one of those little bits kits to play with.  Might be something good to use one of my old laptops for, since it takes practically nothing to run Linux.
Who knows though, maybe I'll end up buying a good high quality function gen before I get it finished......  That's a lot of stuff to learn, but I'm def up for the challenge - once I've got this scope thing down.

Well, time to hook up the scope and get going on the stuff that has been suggested I do by TK and PW.... that is, until I have to go grocery shopping.  It seems like time just flies by...  where's that fancy remote that slows everything but you down?

Brian

[Brian516]

MileHigh,

What you think of using this to build a function gen around?

http://parts.arrow.com/item/detail/arrow-development-tools/bemicromax10#2FFJ

Brian