Couldn't resist the offer about $6/pcs at local recycler shop, and I don't even know what to do with these big heatsinks.
Dimension L 28cm , W 16cm , T 5cm with base thickness 12mm. Put few 3 pins semiconductors as size comparisons.
Wow, great deal. They're...substantial!
From my last visit in Shanghai , some nice microscope finally. for 160$
Sounds interesting, magnification ratio? mechanics is ok?
Where did you get it in Shanghai, at the two towers at East Beijing Rd?
Magnification is 7-45x. It is the same like this
http://www.amscope.com/stereo-microscopes/7x-45x-trinocular-stereo-zoom-microscope-with-dual-halogen-lights.htmlMechanics is absolutely ok. I think it's the same manufacturer also for amscope
No I didn't fount that at Beijing Rd therefore my colleague in Shanghai order it for me from taobao.
Stand is not good for bigger PCBs but I have some plane with this
as a stand.
Random eBay purchase of old junk to play with. No clue what I had be expecting but I hope the transformer is still good.
I was always intrigued by NTSC signal generators, ever since I saw Vectorscope displays in Amiga magazines when they were reviewing video products.
Hey it was 8$. I want to align my NTSC monitors correctly.
$10 at the local antique radio swap meet.
Guy said it worked until last weekend, but there's an issue with the timebase, dots not moving
$10 at the local antique radio swap meet.
Guy said it worked until last weekend, but there's an issue with the timebase, dots not moving
Hope you get it working.
Me too. Power supply is OK, I can get both dots on the screen and deflect Y, but no X movement.
Service manual? Anyone?
$10 at the local antique radio swap meet.
Guy said it worked until last weekend, but there's an issue with the timebase, dots not moving
Hope you get it working.
Me too. Power supply is OK, I can get both dots on the screen and deflect Y, but no X movement.
Service manual? Anyone?
I'd suggest you checking out Mr. Carlson's video where he repairs an oscilloscope. You might not get the answer you're looking for but it will DEFINITELY shed some light on the issue. His knowledge as well as his videos are out of this world.
$10 at the local antique radio swap meet.
Guy said it worked until last weekend, but there's an issue with the timebase, dots not moving
Hope you get it working.
Me too. Power supply is OK, I can get both dots on the screen and deflect Y, but no X movement.
Service manual? Anyone?
I'd suggest you checking out Mr. Carlson's video where he repairs an oscilloscope. You might not get the answer you're looking for but it will DEFINITELY shed some light on the issue. His knowledge as well as his videos are out of this world.
I've watched it in the past. Actually I half expected to run into him at the swap meet, as he's local to me.
Got this resistance decade box from ebay :
Another bargin (I really drive hard bargins
)
Not quite what I was expecting, larger than I thought.
Quick test with dmm shows ranges ok but a little poor in terms of accuracy, then I noticed it says 5% on the front.
Inside, looks like lots of 5 or 10 watt wire wound resistors.
Not sure why I would need resistance box which is capable of dissipating power but hey it works.
Yes, each range is fused.
At what point does it stop being a substitution box and starts being a variable load?
Another bargin (I really drive hard bargins )
Not quite what I was expecting, larger than I thought.
I think this "60 watt" writing on front panel could be a clue;)
It's a very nice device if you deal with power electronics - amplifiers, power supplies and so on, and so on, or for example tube gear. In most cases you don't need 0.1% accuracy, just something to plug in and dial-a-resistance instead of exchanging random power resistors you have in your bin.
Of course if you buy these things to turn dials and watch numbers on multimeter, then it's useless. But if you need to substitute real non-critical accuracy (i.e. everything that isn't part of for example differential amp) resistors during testing, it's better than most small units that would fry when you put an amp or so through them.
At what point does it stop being a substitution box and starts being a variable load?
As far as I can tell, a variable load is pretty much what it is, unless you're tinkering with some new high-power circuit design.
It's hard to tell from the pictures but you might also have a higher voltage rating than most loads.
I didn't buy it on Amazon, but this is what came yesterday:
https://www.amazon.com/ZyXEL-24-Port-Gigabit-Ethernet-Rackmount/dp/B00I126P8UNewegg had it on ebay for $80 just as I was pulling wire and expanding my network. Inside the case I found a 10 pin header giving convenient access to an rs232 serial console. Also I rooted it just for fun.
Today I plan to secure it then swap it in in place of two 8 port switches that are full. I wanted managed switch for vlans and this has more features than I need, but I'm enjoying learning what all those other features are for.
.
just got this box of soldering accessories from China, they added a hot air station & soldering iron too.
its 220V AC . so this is No plug n play unit. its part of a project.
not recommended for professional use IMO, but ok for the weekender.
all I need now is just to lose 25 volts from the Australian AC mains wall outlet.
and see that she's all grounded in reality.
my plan is to use 1000w microwave oven transformer as a step down transformer. add ground tabs and input fuse.
I plan to use a old computer ups power supply case for a box. taping 0v and 240v as input & tapping 0v and 220v as the output.
I'm quite sure it won't mind 245 VAC.
Isn't that Australia has moved to use 230V AC now?
with 1 in 4 Australians now have rooftop solar. it may just top 250v at times. see it flips from 251 to 248 then back to 251.
I may test it at night just to be sure.
I'm quite sure it won't mind 245 VAC.
I need to see a unit working at 240V VAC and not failing. its cheap but not that cheap.
if Dave gave a warning on his video. then maybe I need to be careful.
So many bargains!!!
I'm green with envy. Either I'm failing to be in the right place at the right time OR I'm not looking in the right places!
I've never bagged a bargain anything like what's been listed here!
Back to searching the Web.................
with 1 in 4 Australians now have rooftop solar. it may just top 250v at times. see it flips from 251 to 248 then back to 251.
I may test it at night just to be sure.
Do we need to dust off the autotransformer voltage regulators again we had standing under the valve tvs back in the days?
with 1 in 4 Australians now have rooftop solar. it may just top 250v at times. see it flips from 251 to 248 then back to 251.
I may test it at night just to be sure.
Do we need to dust off the autotransformer voltage regulators again we had standing under the valve tvs back in the days?
It's normal to design gear for 10% tolerance (or even 15% in older devices), so 250V is still in spec for 230V +- 10%
But not for stuff designed ( like many modern components) for a 220VAC supply, and which are often further optimised ( because this means less of that expensive CCA or copper wire is needed) for 200VAC operation. This applies to anything with either a heater or an induction motor in it driven off the mains.
But not for stuff designed ( like many modern components) for a 220VAC supply, and which are often further optimised ( because this means less of that expensive CCA or copper wire is needed) for 200VAC operation. This applies to anything with either a heater or an induction motor in it driven off the mains.
I was mainly thinking about "electronic" devices:) Anyway if a device is meant to be used at 220VAC (i.e. for local China market), designed for 200VAC (for cost saving) and badge-engineered for 230VAC (to sell it in Europe/Australia) then I'm not sure I'd want to use such product anywhere.
Other side of the voltage conundrum is too low voltage. Few months ago I had some power grid failure locally and for few hours instead of 230V-230V-230V three phase supply there was around 80V-0V-0V. It killed all relays in my exterior lights setup as of course there was not enough current going through relay coils. I also learned this way that 1) I could make an awesome techno party with all the strobes going on from LED lights, 2)my computer's PSU can run on 80V (I didn't run any heavy tasks on it of course and checked if cable wasn't getting too hot, no problems whatsoever)
Next day I installed incandescent bulb in the toilet, trying to "read a magazine" with flashing lights was life-changing experience.