Author Topic: Digital oscilloscope project/kit (Read 305986 times)

John Rudd · « **Reply #200 on:** January 16, 2016, 11:17:57 AM »

You managed to chip off all the slag around those welded joints then Rob?

Gotta admit, that seller does have quite a few good projects...

but I dont really need any more test gear......

Owon double beam digital scope with lcd display

2 x 30 v 3 A twin channel power supplies

Digital frequency counter

Lcd scope with frequency meter/ waveform generator

3 x UT 50 dvms etc etc.....

Aint got a bench big enough....or room for one

wheeltapper · « **Reply #201 on:** January 16, 2016, 11:37:51 AM »

Oh do slow down for Pete's sake

I haven't had time to build the component tester yet, and I somehow ordered the signal generator and power supply.

there just aren't enough hours in the day.

Still, it's too damn cold to go out and play with metal things so I suppose I have to have something to do.
Thank gawd this stuff's cheap.

Come to think of it, I can't offhand think of a use for a frequency meter, in fact, I can't think of a use for any of it but it keeps me off the street corners I suppose.

Roy.

John Rudd · « **Reply #202 on:** January 16, 2016, 11:59:03 AM »

Roy,
Damn right about the cold....brrrrrrr 3 degrees here east of Hull....( dont burst into song...."when will I see you again...?" )....

Went into the garage this pm, feet too cold....back into house....Might get the soldering iron out to sort some electronic stuff...

RobWilson · « **Reply #203 on:** January 16, 2016, 12:00:51 PM »

Quote from: John Rudd on January 16, 2016, 11:17:57 AM

You managed to chip off all the slag around those welded joints then Rob?

Gotta admit, that seller does have quite a few good projects... but I dont really need any more test gear......

The slag just peeled off John

, I am finding the kits quite fun to build , just something to mess with in the warm .

Quote from: wheeltapper on January 16, 2016, 11:37:51 AM

Come to think of it, I can't offhand think of a use for a frequency meter, in fact, I can't think of a use for any of it but it keeps me off the street corners I suppose.

Roy.

, I have no idea either Roy ,,,,,,,,,,,,,,,,

,,,,,,,,,,,,,,,,,,but it did keep me out of trouble for an hour

awemawson · « **Reply #204 on:** January 16, 2016, 12:07:27 PM »

Was it is with you lot and these electronic kits - don't you have enough to keep you busy in your workshops already

If you've time on your hands you'd better come on down and help me with my backlog

wheeltapper · « **Reply #205 on:** January 16, 2016, 12:22:01 PM »

I'll go back out to my shop when my skin stops freezing to the machinery.

Roy.

PekkaNF · « **Reply #206 on:** January 16, 2016, 02:02:18 PM »

Very tempted to buy one oscilloscope kit. There does not seem to be external triggering. I was checkking the same type two channel scopes (could use another channel for triggering and it would show the trigger point on the screen) but they were whole lot more complicated or too expensive to justify.

I checked some readymade modules too, they don't look much better on display or sampling rate.

Pekka

John Swift · « **Reply #207 on:** January 16, 2016, 02:26:54 PM »

I guess you could duplicate the Y amp up to TP3
disconnect R13 from TP3 and add a switch to select Y or external trigger source

krv3000 · « **Reply #208 on:** January 16, 2016, 06:33:10 PM »

brill

John Stevenson · « **Reply #209 on:** January 16, 2016, 06:59:53 PM »

You need a decent heater in the shop.

awemawson · « **Reply #210 on:** January 17, 2016, 04:03:23 AM »

Heated & well insulated workshop is essential if you want to play all day

Down side is the running costs - just had the workshop oil tank topped up on Friday - 425 litres since August - the house only used 500 litres

Trouble is I have a roller shutter door that's probably 15 foot square and virtually impossible to insulate and yet still use so that is a huge thermal load. Rest of the building is very well insulated

mattinker · « **Reply #211 on:** January 17, 2016, 05:39:02 AM »

I'm getting a bit OT here for which I apologise!

Andrew,
I realise that your roller shutters are in use so my solution doesn't apply, but I found a source of free for collection high quality insulation panels to insulate my workshop. A friend of mine works as a salesman for a fridge truck body builder. When fridge trucks try to get through bridges that are too low, crunching the front, the entire roof and side sections have to be replaced. It costs them money to get rid of the stuff, 5cm thick high insulation foam sheathed with a skin of polyester and fibreglass on both sides. In some parts it even comes with a stainless facing and tie down points. I made my double doors (twice 4m x 2m )with a large "pop hole" door in one of them. They are hung on bearings, the doors themselves are clad with wood and are a total of six inches thick!

So free to collect insulation, the only thing is I had to wait until the had a body to build! I cut the panels of the body to sizes that needed just a little trimming when I got them home.

Joules · « **Reply #212 on:** January 17, 2016, 06:45:07 AM »

Just walked out to the workshop here.... 1.3℃ lit stove and walked back into warm house and fired up CAD machine

awemawson · « **Reply #213 on:** January 17, 2016, 07:54:53 AM »

Well Matthew I did ask Penny if she fancied making some very heavy curtains to help insulate the roller shutter door, but I got a VERY old fashioned look in return

I dropped the subject after that

I have my oil fired central heating in the barn set to 7.5 deg C over night and 17 deg C during daytime. With our first fall of snow this year on the ground outside it hadn't managed to get to set point - sitting at 16 deg C

awemawson · « **Reply #214 on:** January 17, 2016, 07:57:07 AM »

Quote from: John Stevenson on January 16, 2016, 06:59:53 PM

You need a decent heater in the shop.

Now we can all make a copy of your Chubb key John

John Stevenson · « **Reply #215 on:** January 17, 2016, 11:54:03 AM »

Wouldn't do you any good Andrew. the lock was used to lock the big double doors for the INSIDE.
The insurers weren't happy that I had them secure from the inside with a big M16 nut and bolt, they won't open from the outside.
When I pointed out that once they were INSIDE they had access to plasma cutters still saws, grinders, oxy acetylene, chisels etc it went over their heads so we bought a lock just to keep them happy.

Now I have swapped companies the lock is clipped to the security bars and we are back to the M16 nut and bolt.

The other keys are for me bike lock but I have lost me bike........................

PekkaNF · « **Reply #216 on:** January 17, 2016, 01:25:05 PM »

Quote from: John Swift on January 16, 2016, 02:26:54 PM

I guess you could duplicate the Y amp up to TP3
disconnect R13 from TP3 and add a switch to select Y or external trigger source

Oh, that will clear it!

I had wrong diagram! Found all relevat parts on:
DSO 138 Oscilloscope DIY Kit
Rev. 04 Applicable models: 13803K, 13804K

Starts to look very promissing!

Thank you very much!

Pekka

wheeltapper · « **Reply #217 on:** January 17, 2016, 04:05:07 PM »

I've spent the afternoon assembling the component tester and it's case and it appears to work perfectly.

there weren't any

either.

trying to figure out the calibration was a bit of a bugger, there are online instructions but they aren't very clear...................or I'm thick

choose whichever you like.

Roy.

hermetic · « **Reply #218 on:** January 17, 2016, 07:21:32 PM »

Andrew, I have seen curtains made from 2 layers of bubblewrap hung inside roller shutters, keeps it a lot warmer.
Phil

John Swift · « **Reply #219 on:** January 22, 2016, 06:32:44 PM »

decided to assemble my DSO138 oscilloscope kit this afternoon
it worked first time even though the solder didn't flow that well on the surface mount components - an excuse to buy a smt work station I think ?

for now I've used the switches provided but may change them when I mount it in a box
modding is a must !

two things needs investigating
the variable capacitor C6 does not appear to do much
and the trace shows some noise from the power supply
http://forum.banggood.com/forum-topic-61279.html

John

added picture of screen showing the noise on the trace -
not too bad considering its a £15 kit

PK · « **Reply #220 on:** January 22, 2016, 07:40:19 PM »

Quote from: John Swift on January 22, 2016, 06:32:44 PM

decided to assemble my DSO138 oscilloscope kit this afternoon
it worked first time even though the solder didn't flow that well on the surface mount components - an excuse to buy a smt work station I think ?

Heat and flux are the key, use plenty of both and avoid lead free solder.

Quote

and the trace shows some noise from the power supply
http://forum.banggood.com/forum-topic-61279.html

We keep a bag of 1000uF caps. Mostly for investigating these sorts of problems. But sometimes, on a one off job, they just get left in place.

RobWilson · « **Reply #221 on:** January 23, 2016, 04:08:35 AM »

Quote from: wheeltapper on January 17, 2016, 04:05:07 PM

I've spent the afternoon assembling the component tester and it's case and it appears to work perfectly.

there weren't any either.

trying to figure out the calibration was a bit of a bugger, there are online instructions but they aren't very clear...................or I'm thick
choose whichever you like.

Roy.

Nice one Roy

, I added the three fly leads to mine which made calibrating easier

Quote from: John Swift on January 22, 2016, 06:32:44 PM

decided to assemble my DSO138 oscilloscope kit this afternoon
it worked first time even though the solder didn't flow that well on the surface mount components - an excuse to buy a smt work station I think ?

for now I've used the switches provided but may change them when I mount it in a box
modding is a must !

two things needs investigating
the variable capacitor C6 does not appear to do much
and the trace shows some noise from the power supply
http://forum.banggood.com/forum-topic-61279.html

John

added picture of screen showing the noise on the trace -
not too bad considering its a £15 kit

Hi John ,

Some how I just knew you would find putting the DSO kit together to be a walk in the park

do you think the noise problem is fixable ?

Oh yes modding is a must lol , when you find a source of good quality switches could you post a link to them please so I may purchase some replacements

Cheers Rob

wheeltapper · « **Reply #222 on:** January 23, 2016, 05:59:09 AM »

Hi Rob.
this is mine in it's case.

and here are the flyleads I modded on to a 3 pin header that plugs into the front socket.

Roy.

RobWilson · « **Reply #223 on:** January 23, 2016, 06:18:02 AM »

Hi Roy ,

That looks great

,methinks I should have maybe went for the one with the enclosure .

Cheers Rob

hopefuldave · « **Reply #224 on:** January 23, 2016, 06:12:26 PM »

Quote from: John Rudd on January 16, 2016, 11:17:57 AM

You managed to chip off all the slag around those welded joints then Rob?

Gotta admit, that seller does have quite a few good projects... but I dont really need any more test gear......

Owon double beam digital scope with lcd display

2 x 30 v 3 A twin channel power supplies

Digital frequency counter

Lcd scope with frequency meter/ waveform generator

3 x UT 50 dvms etc etc.....

Aint got a bench big enough....or room for one

Wot, no Spectrum Analyser? RF signal generator? Counter/Timer? GPIB controller?

What I *could* use at the moment is a decent / cheap LCR meter, I have to take stuff to work for one of the ladies to measure (overkill really, 6-digit precision...)

Dave H. (the other one)

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Author Topic: Digital oscilloscope project/kit (Read 305986 times)

RobWilson

RobWilson

RobWilson