BWD 824 35MHz 'scope - opinions? - Page 1
Forum section: electronics / general

author: Greg323i
author_rank: Contributor
timestamp: March 11, 2012, 05:53:16 pm
content: I'm relatively new here and I just bought the above scope for $50. It seems to be in pretty good condition, but may need a bit of calibrating. I'm just a hobbyist into musical electronics, mostly. I'm interested to know if anyone has any experience with this scope and would share what they know.ThanksI forgot to mention, I also bought two probes (Uni-T 60MHz 1x:10x) from a seller on ebay and they look to be pretty good quality and I couldn't beat the price.

author: T4P
author_rank: Super Contributor
timestamp: March 11, 2012, 06:22:32 pm
content: What can i say ? It's all good , for a beginner's scope . Oh remember to upgrade both your probe and your scope in the future .

author: amspire
author_rank: Super Contributor
timestamp: March 11, 2012, 10:08:08 pm
content: It is a good basic oscilloscope. Manual easily available:http://bama.edebris.com/download/bwd/824/BWD%20824_001.pdfBuilt from standard parts, so fairly easy to service. Good manual.It is missing the delayed sweep of the higher end analog scopes, but it is not a bad scope at all. I think you have done well.Richard.

author: Greg323i
author_rank: Contributor
timestamp: March 12, 2012, 01:34:58 am
content: Thanks for the link Richard, BAMA is a great site. It was the first thing I did when I was considering the scope. A friend and I each bought one from a university and we had a look at his on Saturday and it looks to be great for what I need. I imagine if I get in to digital electronics then I would soon outgrow it, but I don't see that happening soon.

author: amspire
author_rank: Super Contributor
timestamp: March 12, 2012, 02:03:12 am
content: The beauty of owning a reliable analog scope is they will probably become very hard to get new soon, and they are just great to have even if you later get a digital scope. There is currently a massive effort in the digital scope world to try and equal the performance of analog scopes for things like transient detection in switching waveforms.35MHz is good enough to see waveforms on most the the kind of circuits you will probably start with - like Arduinos, control circuits, audio, etc.Richard.

author: vk6zgo
author_rank: Super Contributor
timestamp: March 12, 2012, 03:14:51 am
content: The great thing about BWDs is that they almost always have a nice,bright,display.Good choice of a CRT,I guess.The two bad things about a BWD are:(1) Many of them lose their triggering when they get old.There is a voltage divider at the output of the vert amp,right up near where it drives the vert plates.This supplies a small level of vertical signal to the triggering circuit.The high value resistor in the divider goes even higher in resistance with age,until this signal level is insufficient for reliable triggering.This brings me to bad thing (2)They are very difficult to troubleshoot,as the boards are tucked away under the tube,limiting access.If it is working OK,it is a very useful 'scope for most general work,really a step up from the "cheapy" 10MHz Chinese analogs.

author: amspire
author_rank: Super Contributor
timestamp: March 12, 2012, 04:35:16 am
content: The internal trigger in the BWD824 is from the preamp stage, not the vertical amps, so there is no high voltage divider involved. it is just capacitor coupling.With luck, that means the trigger circuit will work fine.It looks like there is no delay line before the vertical amp. It is normally there so you can actually view the trigger event on the screen. You cannot with this scope. That is a definite limitation. Just for that reason alone, I would probably keep my eyes open for a cheap upgrade opportunity.Richard.

author: vk6zgo
author_rank: Super Contributor
timestamp: March 12, 2012, 06:09:32 am
content: Yep!I got it wrong!The earlier single beam BWDs used the method I described,but I should have stopped to think that it wouldn't allow you to change the triggering for a dual beam CRO.My Bad!

author: EEVblog
author_rank: Unknown
timestamp: March 12, 2012, 11:21:55 am
content: A classic analog scope, that will serve you well I'm sure.Australian made!Dave.