new scope

Huh, well a bit less than Butterworth, but not Gaussain/Bessel. 'We' should demand a nice step.

I saw ads/emails for new Rigols with knobs for each voltage input. That's what I've been asking for... that should be my next 'scope I think ~$700 at the low end... the price might come down. :^)

George H.

It's gorgeous compared to most other fast scopes. I've seen some real horrors.

Which is weird, bacause it wouldn't take much math to make a digital scope's step response visually perfect.

If you watch the Austrailian guy whose accent you can't stand, he traced a lot of the circuit especially the front ends of several Rigols. The bandwidth is software controlled by RC filters that are selected by common-emitter switches between the C and ground.

They could have done some of the bw limiting in software, and preserved a nice transient response. But that's no big deal.

It's a really nice scope. My test people have I thgink 6 of them, and have an extensive Python library to talk to them. The next test set I design will be one custom signal switching PCB and one of these scopes. The scope replaces a $1K DVM and a $5K counter.

Nice. We boat-anchor fans have ways of getting to the same sort of thing, though without the nice serial decode and so on. (I'll have to get a scope that does that at some point.)

I got another TDS 744A off eBay for $350--some guy had tried to mod it into a 784A by removing the bandwidth limiting caps and one of the programming jumpers, according to the instructions on the Web. However, he followed the wrong set of directions (probably the EEVblog thread) and removed jumper R1061, which gets you the 1 GS/s "export mode". A 1 GHz, 1 GS/s scope isn't that saleable, I imagine. ;)

If you remove R1064 instead, you get the normal 4 GS/s mode and it identifies itself as a 784A at power-up. Dashing Firmware Hunchback and I put in one of the Newscope LED display kits, and the result is _beautiful_--a brighter-than-new TDS 784A with a pretty clean 400 ps step response, all for $700. It even works and triggers on all 4 channels.

(The amount of time required made it totally uneconomic, of course, but you have to do some head maintenance sometimes.)

Now I have to do my other one, the one that passes SPC. ;)

Cheers

Phil Hobbs

Keeping stuff working is good for the soul. I've never counted my time. (I'd probably pay myself too much, and then it wouldn't be worth it to fix the ...xxxx.)

George H.

Dashing Firmware Hunchback?

Sounds like a regular kind of guy.

title is Chief Designer and mostly does PCB layouts, and Simon, whose title is Chief Scientist and does FPGAs and manly stuff like that. We tease each other a lot, and one of my running jokes is "you can't get good hunchbacks nowadays." By extension, the one became Beautiful Layout Hunchback and the other, Dashing Firmware Hunchback.

They do proprietary work for the company and also client work. BLH is moving to Texas in a month or so, so I'll be needing a new layout person by about Easter, or whenever she gets a real job down there.

Cheers

Phil Hobbs

Nepotism!

I work for The Brat now... she's running the company. She was the best PCB layouter that I ever worked with, and she and I both miss her doing that. She especially loved routing BGAs.