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Test Equipment / Anyone experience with TM-600 VDSL2 testing device
« Last post by Emo on Today at 11:34:36 AM »
Hi I am currently involved in a VDSL rollout in the caribbean and looking for an affordable VDSL capable field tester. Some known equipment is either very expensive, not capable or not produced any more like the EXFO maxtester/cable shark, Fluke 990 etc.
Main purpose is to be able to test VDSL2 using profile 17a modem emulation including all statistics, TDR measurement and plain impedance/balance properties.
One of the chineese suppliers does deliver an all in one affordable box that seems to meet most of the specs, the TM-600. However no reviews can be found at this time. If someone does have info on this instrument I would appreciate some feedback.


For EMC pre-compliance testing you'll need a spectrum analyser because an oscilloscope is not sensitive enough. You'll need to measure signals with an amplitude in the low uV range and a generic oscilloscope doesn't do that. IMHO the MDO2000 series from GW Instek isn't worth the extra money compared to the GDS2000E series. All the MDO seems to add is a more fancy FFT display.
Pet tags use a rod antenna which is rather orientation sensitive - you may be able to at least  improve consistency of read range using multiple antennas in different orientations.
Repair / Re: Fluke 8800A
« Last post by neo on Today at 11:28:02 AM »
I got the OHMs working, contact broke. Fixed it ans is now good as when i got it.
General Chat / Re: What did you buy today? Post your latest purchase!
« Last post by Specmaster on Today at 11:26:55 AM »
A flux pen and a jar of tip restorer plus a new desk chair.
Beginners / Re: Used Oscilloscope for under 250$
« Last post by Shawnk on Today at 11:26:42 AM »
Ok thank you for the info.  On my scope i was trying to watch the Tl494 driver for the switching power supply and i could only see a straight line because 1ms time is my fastest  resolution.
Assuming your RCD is also the overload protector (circuit breaker in US power terms), it might be the surge current.

I had a similar problem with a saw and found that they make "High Magnetic" breakers which allow a larger short term surge, but have the same long term limits.  I checked that the wire was bigger than the minimum and fairly short before installing one.
I have a Dell U2212HMc monitor my goal is to repair it to a mostly functional state.
The problem is the power supply has failed and because I'm not the greatest at the electronics :-// and I suspect multiple parts have failed I have decided to try and replace the functions of the board.

The power board (715G4542-P03-000-0H1H) has three main functions. It supplies 5 volts to the controller board, some audio stuff to deal with an external sound bar (irrelevant) and the LCD panel driver.

The LCD panel driver is the only part of the board I'm interested in. Thankfully it is nicely isolated so it's easy to see what traces are going into that area. Unfortunately I've been unable to identify what two of the traces do I believe one of the traces is for a lower voltage for the driver chip and the other is a higher voltage for the LCD panel. The ones I have identified are ground and some dim controls. I've tried to find schematics but I've been unable to find some.

So I have came to this forum in a last ditch effort to try and fix or replace this board I will attach some other stuff I have found.\

So what I would like from you people is you help, advice maybe some schematics, anything really I've done as much as I can on my own. you need any information from me definitely ask you can get me on discord at ashlin4010#9723

Thank you
Has anyone come across any readily available good and cheap SMA(f) - BNC(m) adaptors? (not surplus expensive ones, but cheap when bought new)

The main problem with most of the cheap BNC adaptors and plugs that I've seen is that they are missing the raised flange around the end of the ground connection on the plug, so don't connect well with the socket. The plating on a lot of them does not help much either.

I've sometimes bent the contacts out a little so that they connect better, but that's certainly not ideal.
I use these when testing the pulsers.

Thanks, but it was more the ones to allow an SMA based pulser to be used on a BNC scope that I was wondering about, and those are the ones that seem harder to do right - however the “You may also be interested in....” bit on the page that you linked to actually led to fairly cheap ones that at least looked OK. I'll need to try some sometime.
I've had so much trouble with cheap connectors that I tend to buy surplus good ones, which are often not too expensive.

One of the good things about the BNC version of the pulser is that it avoids most folk having to mess with these adaptors.
You can use a true-sine inverter fed by a hot swap server power supply which can be had for next to nothing, then you can get power in the correct frequency even. I use such a setup to get 240V 50Hz in the US when I was playing more with HID and fluorescent lamps and wanted to properly power the European stuff here.
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