Be in touch with your business needs as they relate to your oscilloscope needs. Are you going to faster designs soon that might impact the banner specifications you'll need in the near future?
Write down exactly what you expect the new oscilloscope to do. Make it your "wish list". Try to find out what the most popular oscilloscope is for your application.
Get a sense of how solid your budget is and how soon you can place an order once you make a decision. If it is > 6 months away and your short term needs are critical, consider rental or lease.
Plan several different demos with different manufacturers. Let them know it is a "competitive situation" and you want the best oscilloscope you can get that meets your needs. You'll get a lot of attention and the best of services.
Schedule the demos in your lab instead of your conference room. You'll be closer to your signals and the real environment (what noise?) Where the oscilloscope will have to work.
You should plan to see a demo of the exact model oscilloscope you are thinking of using - with all the options you believe you'll need - conducted by a Sales Engineer that knows the instrument and what you need it to do extremely well.
The oscilloscope manufacturer's Sales Engineer should be a great resource to you. By reviewing your application and assisting you with a platform selection that is technically correct, your demo will be much less likely to disappoint you or anyone else.
If you have never met the Sales Engineer, plan to start with a quick tour of your facility. Explain why you need the oscilloscope showing them the area that it will be used in and what you expect it to do. The tour may let your sales engineer see things that will help you that you hadn't thought about and offer you a conscious review of what you are trying to do.
A quick overview of the oscilloscope's banner specifications and key features is a good place to start the demo. Focus quickly on how to drive the front panel and how to extract the various functions. If it looks complex, save front panels you'll need to recall. Ask questions.
You should see your signals on screen early into the demo and plan to borrow the oscilloscope for at least a few days to evaluate it if the demo goes well.
The demo should prove that the oscilloscope model being demoed can do your specific application(s). If the demo can't do that, you are probably wasting time by evaluating it further after the demo. If the oscilloscope has to do a specific task, see it happen at the demo and learn how to replicate the settings so you can do it after the Sales Engineer leaves.
Pay attention to the number of buttons that have to get pushed to go from one operation to the next. If the demo is really canned, force some hopping around so you see typical vs. streamlined operation.
Find out how long the oscilloscope platform you are looking at has been on the market. Ask for mtbf figures (mean time between failures). Find out where the closest service center is and how long a typical repair or calibration turnaround might take.
If you are with a large company, find out who else in your company is using the same/similar oscilloscope from the sales engineer. Chat with the other users.
If you are with a small company, find out who else in your industry within your area is using the same/similar oscilloscope from the Sales Engineer. Chat with the other users.
Take as much time as you like. Don't rush it. Ask questions. Record answers. Enjoy the process.
Check the demo oscilloscope that will be left for evaluation to make sure:
That it will accept your full scale voltages
That it samples fast enough to capture your waveforms with high fidelity
That it is not affected by other signals in your environment
That it has the options necessary to take your measurements
That it has a manual covering operations
That you have access to their applications engineering during your evaluation
Make notes of the questions you have and record the answers. It will keep you focused.
Call the factory's application's group and test them to see how well they answer your questions. Get all application notes sent to you that address your areas of interest.
Don't believe there is one oscilloscope that does everything. Many labs have a variety of scopes for various specialized functions.
Try this experiment with the oscilloscope you are considering. Connect a signal source up to the oscilloscope where you can vary the amplitude of the signal by very small amounts. The waveform should have at least 3 or 4 complete cycles on screen and be 90% of full scale.
Once you have a stable trigger, store a copy of the waveform into a reference memory. Then activate math so that all new waveforms are being subtracted from the waveform in reference memory. See how little you can change the amplitude level on the generator to see and measure the difference with the oscilloscope. A large part of the utility of an oscilloscope is verifying that things are exactly as they should be and seeing the difference.
If the oscilloscope didn't meet your expectations, make sure you know why and include the new issues you've discovered in your wish list.
Get a list of all options available for the oscilloscope so that you can order the exact configuration that really addresses your needs.
Make sure you and your Sales Engineer determine issues that might
include:
You should also explore the manufacturer's policies and costs regarding:
Applications Assistance
Calibrations- NIST, MIL, Performance Checks, ISO-9000, At-site Service
Capabilities For Training Users
Oscilloscope System Software/firmware Upgrades
Warranty Period- Extensions
Get a written quotation that relates the platform, specifications, options, all costs, delivery, and any discounts available. Most manufacturers offer educational, GSA, quantity, and/or demo discounts if you qualify.
You might also consider rental or leasing options. Most rental companies offer equity rentals where rental/lease fees apply towards your purchase.