Few modifications

Few modifications

Postby racunalac » Wed Oct 19, 2016 2:10 pm

For these mods you need basic knowledge of electronic circuits and soldering skills.

MOD1: Power switch

Adds switch on position of diode D2 so that oscilloscope can be switched on or off without pulling cable from power supply.

Parts:
-perfboard strip (6 holes, 1 row),
-PCB slide switch,
-Diode (you can use 1N4004 from kit or similar, even Schottky diode as they have lower voltage dropout, it is just for reverse polarity protection)

Pins 1 and 2 on switch are connected with piece of hard wire (obtained from trimming leads from components after soldering them). Pin 3 from switch is connected to anode on diode. Wire and cathode lead should be long enough so that newly created board can be soldered instead of diode D2. If board is mounted as I did it position of switch shown in picture is OFF position. If you wish to reverse switch position, for on and off positions, then solder wire to pin 1 of switch and pins 2 and 3 to cathode of diode. Diode orientation and position MUST be as shown on picture. Otherwise it won’t work.

Image

MOD2: Power over USB
Adds power over micro USB and power over preinstalled mini USB on board in parallel with power jacks J9 and J10

Parts:
-micro USB boost converter
-Colored wires
-Diode (same as MOD 1, it is just for protection against plugging simultaneously USB and DC jack)

First set boost converter to output of 9V + voltage drop at diode by turning potentiometer. You can replace potentiometer with fixed value resistor as I did or once set just leave it. In my case resistor value of 33k will give output voltage of 8,87V from boost converter, but my voltage drop at diode is only 0,23V so that works in my case) After that, connect everything as shown in picture and you can power it from on board mini USB, micro USB or adapter connected to power jack. Inside shrinkwrap is only diode and wires clumped together.

Image

MOD3: Lower noise mod (before latest update)

Same as shown in this topic:
viewtopic.php?f=18&t=542&p=1227

Image

DISCALMER: I am not responsible for any damage that you do to your kit due to lack of knowledge or doing something differently from what I have shown here.
These mods are tested and they are working perfectly on my scope. Basically switch mod is something that board should have in first place because it is pretty useful and second mod is modification of JYE140 - Step-up DC/DC Converter only with different boost converter.

Why I did those mods?? For this:

Image

I have mounted oscilloscope and transistor tester on board and they are always on my desktop when I need them and are powered from same micro USB connector.
If you have any questions about mods please ask and I will try to answer them.

PS: I apologize for my grammatical mistakes because my English is not my native language.
racunalac
 
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Joined: Sat Sep 24, 2016 1:01 pm

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