Yes Led powerd on, shows hundreds of scribbles
During the compilation the program was 105.6% full and the new hex file size is 96KB compare to the original hex file of 83KB.
Hello, considering getting one of these ESR kits to build. Had a look on bangGood, and there are a few to choose from.
Can someone recommend the darling? Is bangGood best bet, or aliexpress/ebay offer better ones or prices?
M328 LCD 12864 Transistor Tester DIY Kit Diode Triode Capacitance LCR ESR Meter $22.85au
http://www.banggood.com/M328-LCD-12864-Transistor-Tester-DIY-Kit-Diode-Triode-Capacitance-LCR-ESR-Meter-p-1041588.html
DIY M12864 Graphics Version Transistor Tester Kit LCR ESR PWM $25.67 (cant see difference)
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-p-986954.html
DIY M12864 Graphics Version Transistor Tester Kit LCR ESR PWM With Case $31.58
http://www.banggood.com/DIY-M12864-Graphics-Version-Transistor-Tester-Kit-LCR-ESR-PWM-With-Case-p-997023.html
is the case worth $9 more. Seem to recall allignmnt issues.
GM328A Transistor Tester Graphic Wave Signal LCRRLCPWMESR Meter Inductance $20.44
http://www.banggood.com/GM328A-Transistor-Tester-Graphic-Wave-Signal-LCRRLCPWMESR-Meter-Inductance-p-997582.html
DIY Multifunction Transistor Tester Kit For LCR ESR Transistor PWM Signal Generator M328 $15.53
http://www.banggood.com/DIY-Meter-Tester-Kit-For-Capacitance-ESR-Inductance-Resistor-NPN-PNP-p-929603.html
I am going to use "Atmega328P 5V 16 MHz Arduino Pro Mini" as 2x16 LCD tester with these steps:
- remove original AREF capacitor and use smaller value 1 nF,
- connect LCD module, test button + resistor (PD7) , 2,5 V reference (PC4) and 6 resistors 1%,
- rebuild Markus 1.21 classic project to 16 MHz clock (WinAVR 20100110).
Should I do something additional?
Should I use ISP programmer (ISP connector + USBasp) or original Arduino bootloader via USB/RS232 TTL dongle?
I just added a relay for input protection on my LCR-T4 tester. Upon careful examination of the suggested circuit in the originator's manual, I see a major design flaw of the relay driving circuit.
The relay is driven with a bipolar transistor from the TL431 2.5v reference voltage through a 4.7k resistor. The transistor base current would be (2.5-0.7)/4.7k=0.38mA. To drive the transistor into saturation, the transistor collector current would be only 0.38*10=3.8mA.
The hFE you are talking about is NOT for VCE(sat). The hFE of 100-450 is specified at VCE of 5v-10v depends on who is the manufacturer of this BC547.
The hFE for VCE(sat) on this BC547 is specified at 20, most common transistors in the US like 2N3904 and PN2222, the hFE for VCE(sat) is always specified at 10. Even if you use hFE as 20, you still don't have sufficient base current to activate the relay.
With all due respect, "rule of thumb" are not part of any manufactures specs. That is why EVERY bipolar transistor has a VCE(sat) specified at a specific Ic and Ib. BTW, I am an EE with over 30 years of hardware design experience and I never heard this rule of thumb.
With all due respect, "rule of thumb" are not part of any manufactures specs. That is why EVERY bipolar transistor has a VCE(sat) specified at a specific Ic and Ib.
Any curves on datasheets are typical and are not guaranteed at all.
My point also is that it really doesn't cost you anything extra to do it right.