Got both a DCA75 and ESR70. Both are working fine and the curve tracer function on the DCA75 helped my identify lots of bad little guys in various old amplifiers. Wish there was a bigger version, maybe with a 3" display or so, to show curves as a quick test method, without the need of a computer.
I love these UK made Peak testers, but don't own one (yet), however the one you showed here seems sadly a bit lacking - it really ought to produce those curves much faster! Diodegonewild made an excellent video on measuring zener diode characteristics recently.
12:09 Calling a uPC574 a voltage source is kind of wrong. It is a temperature drift compensated 33V zener used to stabilize the tuning voltage feed on tuners. So unless that craptastic tester puts out more than 33V, the uPC574 will always be recognized as a simple diode only.
Mmmm, don‘t you need to understand the limitations of the tester before concluding? It seems obvious that the tester cannot sweep negative voltages. Thus, it cannot test an 7905. And for a Zener, why did you not try to connect the zener reversed instead of assuming the tester sweeps negative?
Indeed. It is sad to see someone do a review when he doesnt even understand the limitations of the device. There can never be anything like the all knowing and all identifying tester. No tester will ever replace the human who with knowledge and common sense interprets the test results of the machine.
My DCA75 can identify a 7805, but not 78/7912 (can't find any 7905s). However, the manual states it would "typically" identify regulators with an output less than 8v. The manual also makes the fair point that some regulators are unstable without their decoupling capacitors or not under load. I have observed some 78/79 regulators to go a little crazy with no decoupling caps, others are fine. Still, it's useful for a pocket-size tester. A little (ok, a lot) overpriced, but then it's probably the second newly purchased thing I own that says "Made in England" (the first thing being the ESR70) so maybe arguments could be made the purchase is morally justified over something cheap from Ali Express!
First time visiting your channel.I quite fancied one of these but this video has put me off a little,maybe future updates may sort a few bugs out,just a shame about the low voltages it can only handle.
You've made a nice presentation of its capabilities. I contacted and corresponded with technical department with my suggestions for improving their graphics handling. They made no changes and have not upgraded software since I bought my '75. Perhaps the sales have fallen off and they are dropping support/upgrades?
Regarding the spreadsheet question, in LibreOffice you would just add more data series for additional curves. Double click graph to edit, right click, than select Data Ranges from the context menu, and the required dialog will pop up. And no, I do not consider myself a spreadsheet wizard. ;)
I tried to do that before I made the video but it wasn't at all clear to me how to get the extra data ranges to display properly. Hence I could use someone to put together such a sheet. I could publish a set of sample data if you think you could make up a better set of curves and we can then provide that sheet for other people to drop their data into.
@@video99couk Sure, go ahead, I was going to suggest publishing a set of data to play around with anyway. I have not paid much attention to what happened to "classic" OOo after LibreOffice split off, I could imagine that many of the improvements that the latter received in recent years may have passed it by and that's the reason why you couldn't make multiple curves work properly.
You can easily add more curves to a chart by copying just the cell range with the values and pasting it on the chart. Wprks well assuming the x axis values are identical.
I have mixed feelings with the DCA-75 curve tracer. I think voltage and current are too low for testing power transistors. Some days ago I am testing some noisly transistors without success, transistor pass the test without any fault.
I does'nt look like they tested it before it went on sale. Just like the software industry, let's sell it now and any bugs, we'll fix them with updates. 😢
Thank you Colin great episode. I am an old dog which is learning new tricks. Cheers
Got both a DCA75 and ESR70. Both are working fine and the curve tracer function on the DCA75 helped my identify lots of bad little guys in various old amplifiers. Wish there was a bigger version, maybe with a 3" display or so, to show curves as a quick test method, without the need of a computer.
I love these UK made Peak testers, but don't own one (yet), however the one you showed here seems sadly a bit lacking - it really ought to produce those curves much faster! Diodegonewild made an excellent video on measuring zener diode characteristics recently.
12:09 Calling a uPC574 a voltage source is kind of wrong. It is a temperature drift compensated 33V zener used to stabilize the tuning voltage feed on tuners. So unless that craptastic tester puts out more than 33V, the uPC574 will always be recognized as a simple diode only.
Mmmm, don‘t you need to understand the limitations of the tester before concluding? It seems obvious that the tester cannot sweep negative voltages. Thus, it cannot test an 7905. And for a Zener, why did you not try to connect the zener reversed instead of assuming the tester sweeps negative?
There's an option for the zener graph bottom left to set the bias direction, which I hadn't spotted at the time.
Indeed. It is sad to see someone do a review when he doesnt even understand the limitations of the device.
There can never be anything like the all knowing and all identifying tester.
No tester will ever replace the human who with knowledge and common sense interprets the test results of the machine.
My DCA75 can identify a 7805, but not 78/7912 (can't find any 7905s). However, the manual states it would "typically" identify regulators with an output less than 8v. The manual also makes the fair point that some regulators are unstable without their decoupling capacitors or not under load. I have observed some 78/79 regulators to go a little crazy with no decoupling caps, others are fine.
Still, it's useful for a pocket-size tester. A little (ok, a lot) overpriced, but then it's probably the second newly purchased thing I own that says "Made in England" (the first thing being the ESR70) so maybe arguments could be made the purchase is morally justified over something cheap from Ali Express!
I had tried a 7805 with capacitors and it failed with that too. I suspect mine may have a defect.
There's an option for the zener graph bottom left to set the bias direction? And there's a P-N junction tab for the LED.
I'll check those out.
First time visiting your channel.I quite fancied one of these but this video has put me off a little,maybe future updates may sort a few bugs out,just a shame about the low voltages it can only handle.
You've made a nice presentation of its capabilities.
I contacted and corresponded with technical department with my suggestions for improving their graphics handling. They made no changes and have not upgraded software since I bought my '75. Perhaps the sales have fallen off and they are dropping support/upgrades?
I have problems thus unit. I hope for new firmware to fix it. Sometimes, I have to use curve tracer tests Transistor. Plus, DMM.
Regarding the spreadsheet question, in LibreOffice you would just add more data series for additional curves. Double click graph to edit, right click, than select Data Ranges from the context menu, and the required dialog will pop up. And no, I do not consider myself a spreadsheet wizard. ;)
I tried to do that before I made the video but it wasn't at all clear to me how to get the extra data ranges to display properly. Hence I could use someone to put together such a sheet. I could publish a set of sample data if you think you could make up a better set of curves and we can then provide that sheet for other people to drop their data into.
@@video99couk Sure, go ahead, I was going to suggest publishing a set of data to play around with anyway.
I have not paid much attention to what happened to "classic" OOo after LibreOffice split off, I could imagine that many of the improvements that the latter received in recent years may have passed it by and that's the reason why you couldn't make multiple curves work properly.
You can easily add more curves to a chart by copying just the cell range with the values and pasting it on the chart. Wprks well assuming the x axis values are identical.
FA-400 is a nice composite TBC from company For A ;-)
I have mixed feelings with the DCA-75 curve tracer.
I think voltage and current are too low for testing power transistors.
Some days ago I am testing some noisly transistors without success, transistor pass the test without any fault.
Didn't exactly want one after watching this video. It should have been much better. 🤔
I does'nt look like they tested it before it went on sale.
Just like the software industry, let's sell it now and any bugs, we'll fix them with updates. 😢
These are overpriced and will not identify failing (completely open or shorted out will) transistors.