Hey Guys
Here are the PCB files for a through hole version .
Eagle PCB Files Attached
Cheers
Rupert
I have downloaded and attempted to extract the files on 2 different systems. They both indicate that the zip file is empty.
Try now JoeO
I compressed it as a ZIP, the files are also updated.
I had to rename the extention as ZIP as the forum doesnt allow RAR files. This works fine with WinRAR but windows extracter may not like it.
Thanks
Rupert
In terms of compactness and size for a through hole your design beats the pants off whatever I can make. Can you please tell me how you designed it?
Hi group,
It is nice to see other people successfully building the meter
I had designed a thru-hole version of the board. I never built the thru-hole version.
The dimensions are 3.00 x 1.75 inches (75 x 44mm)
The 7805 can be replaced by the 78L05, this saves a lot of space. This layout is single sided. If you use itead you can use both sides and vias.
Regards,
Jay_Diddy_B
Hi Guys,
I had some time over the weekend to etch my through hole PCB design, and calibrate a scale.
The more observant may notice the Easter Egg on the scale ( Mr Jones may have a chuckle)
Looks as if it works great, thanks Jay for sharing
Now I just need to make an enclosure.
PS. The missing 2.2uf caps on the picture are SMD mounted, underneath the PCB
Thanks
Rupert
I had some time over the weekend to etch my through hole PCB design, and calibrate a scale.
Just a quick question.
I've been researching a lot of different DIY ESR builds, and have decided to give this one a try. My question is, would 2N2222 work in place of the 2N3904 transistors? From what I can tell from the data sheets, they seem pretty similar. The reason that I ask is I have a ton of 2N2222's sitting in my parts box.
Just a quick question.
I've been researching a lot of different DIY ESR builds, and have decided to give this one a try. My question is, would 2N2222 work in place of the 2N3904 transistors? From what I can tell from the data sheets, they seem pretty similar. The reason that I ask is I have a ton of 2N2222's sitting in my parts box.
Yes, you can use 2N2222, BC548 will work for European constructors, for the npn transistors.
2N2907 or BC558 etc. will work for the PNP transistor.
Regards,
Jay_Diddy_B
Hi group,
The deflection of the meter versus ESR comes from the properties of the unbalanced bridge circuit used in the design. You can adjust the resistor values in the lower legs of the bridge to bend the meter response.
This is an LTspice model that illustrates the effect of changing the resistor value. I have normalized the models to show 0-100% deflection.
These are the results for 1,3 and 10 Ohms:
3 Ohms was chosen the design to give the best scale on the meter, for the majority of applications.
Most electrolytic capacitors have an ESR less than 20 Ohms, if they are good.
Note: this model does not include the non-linearity introduced by the 1N5711 diodes.
It is not easy to adapt the circuit for a 1mA meter.
Jay_Diddy_B
hi is there a black and white version of the pcb artwork,as having it in color makes it imposible to use the toner transfer method of making the pcb,cheers Paul.