$20 LCR ESR Transistor checker project

[jakeisprobably]

...One last thing, I missed where the xtal tester is. I would like to add that. A xtal upgrade comes when I can get it to work at 8Mhz.

Kübbeler is the keeper of Crystal ball feature at the moment. The Sampling ADC method from K-firm must be enabled as well.

... must have 16mhz xtal as well

[madires]

BTW, there's a nice crystal tester and frequency counter in the extended 644/1284 circuit (see Karl-Heinz' documentation). If I'm not mistaken it should work fine up to 80MHz. And I've got the parts for that already

[scottie4442]

got my set of 3 boards and they look great, now I have to do a BOM and order the parts for this thing.

[N9XYP]

I think SDA should be LCD_SI, and CD should be LCD_A0.

The connection names are from an eBay listing, not sure if they are totally correct. Would the display still work if SDA and CD (LCD_SI and LCD_A0) were reversed? I am asking before I start cutting traces....

[madires]

LCD_SI is the serial data input and LCD_A0 indicates command or data. If they're swapped the display wouldn't even be initialized. Maybe some voltage level problem? The display seems to run with 3.3V and the pull-up resistors of the rotary encoder in parallel are powered by 5V, I'd guess.

[knarfootje]

do you have a BOM by a ditributor ? I'm very interessed if you have

[scottie4442]

I am going through the schematic and making my own BOM so will take a while. I have made the lunk to the board at oshpark available in an earlier post and when I get the BOM done I will post it.

[madires]

Someone has created a public BOM list for Reichelt, but I can't find the URL unfortunately. You should be able to find all parts in Reichelt's online shop, including 0.1% resistors for a reasonable price. If you like to save a few bucks buy displays directly from China.

[scottie4442]

Thanks, I am putting together my BOM from mouser, I know cost a little more but I have done a lot of business with them in the past. The display I will probably get from from China as you suggested, the highest cost item is the zip test socket, that thing is $20US, holy crap.

[j-man]

Hi guys. This thread grew up as an awesome tutorial about ATmega... It's a shame I don't know nothing about programming, I really wish I could learn more.
A couple of quick question: I zapped one of the three ATmega328P input ports of my fish8840 tester, I guess I forgot to discharge a cap... damn. Is it worth to replace the chip, in your opinion? What do I need to send the latest firmware to the new chip, and will it work in that 2014 tester?
Many thanks in advance.

[texaspyro]

I zapped one of the three ATmega328P input ports of my fish8840 tester, I guess I forgot to discharge a cap... damn.

When buying transistor testers remember rule 1:  Only buy models with a socketed processor!  You WILL eventually zap the chip and SMD rework is no fun, even if you have the equipment.    Silicon and magic smoke hate humans and will commit suicide just to spite you.

Plus it is easy to swap in a different chip configured with different firmware options compiled in.

Get the ZIF socket from China...  maybe a buck or two.

[madires]

Yes, an ATmega328P is just two bucks. You need an ISP programmer (3 bucks) or an Arduino with the ISP sketch. k and m-firmware work fine with old tester versions.

[N9XYP]

Found the problem with both the no menu and the bar over the last line. The CS line (pin 11 inter-board) was tied to ground and pin 8,9,10 UNDER the connector as well gound on the soldered side (which I cut when jumpering).

Seems to be working just fine. Need to run the calibration and test a few components. Then comes the 16 MHz xtal.

Thanks again to madires for reminding me to do basic troubleshooting.

[CustomEngineerer]

Thanks, I am putting together my BOM from mouser, I know cost a little more but I have done a lot of business with them in the past. The display I will probably get from from China as you suggested, the highest cost item is the zip test socket, that thing is $20US, holy crap.

$20 zif socket? For that price you could buy one of the unassembled kits and just use the zif socket from it.
As much as I like mouser I would also suggest getting that in addition to the display from elsewhere.

[upsss]

NO need to buy a whole kit, 2 zif socket including shipping for $1.20!

https://www.aliexpress.com/item/2PCS-IC-Test-Universal-ZIF-Socket-14pin-14-pin-dip-2-54mm-IC-Socket-pitch/32506431657.html

[j-man]

Yes, an ATmega328P is just two bucks. You need an ISP programmer (3 bucks) or an Arduino with the ISP sketch. k and m-firmware work fine with old tester versions.

Thanks a lot for your informations. I got a friend that could help me with the programmer... let's see.
Another question: I bought another tester as a gift for a friend, but when I opened the package I found a broken display and the seller has sent me a refund. I'm trying to find a new display: the old looks like an ST7565, but the flat cable has just 12 pins, while the similar displays on eBay and Ali have much larger connectors, with 18 pins or more. Any suggestions are welcome... Many thanks.

[jakeisprobably]

Yes, an ATmega328P is just two bucks. You need an ISP programmer (3 bucks) or an Arduino with the ISP sketch. k and m-firmware work fine with old tester versions.

Thanks a lot for your informations. I got a friend that could help me with the programmer... let's see.
Another question: I bought another tester as a gift for a friend, but when I opened the package I found a broken display and the seller has sent me a refund. I'm trying to find a new display: the old looks like an ST7565, but the flat cable has just 12 pins, while the similar displays on eBay and Ali have much larger connectors, with 18 pins or more. Any suggestions are welcome... Many thanks.

Probably the cheapest source I've seen mentioned for displays (they are also one of the larger sellers of displays on eBay if you would like to pay a little more for the same thing there)
http://www.buydisplay.com/
This is a search for ST7565 based displays:
http://www.buydisplay.com/default/graphic-display?cotroller_ic=445
Tutorial on ST7565's from a reputable source:
http://www.ladyada.net/learn/lcd/st7565.html
  If you really really want to replace the display exactly, it's probably more simple to just buy the whole clone again. Most of the displays sold come with breakout boards so that people don't need to solder ribbon cables directly. However, IIRC, AliExpress had some sellers listing overpriced components specifically listed as "Transistor Tester replacement [x, y, z]." They usually use whatever hair-brain-idiot brand name they made up to sell a clone (hiland, kkmoon, etc.). These names have absolutely zero meaningful value. Others have had issues with the same unit as you and have posted information. Watch the indexes I created and posted on the last page or 2 of this thread to find this information visually.
   As an inexperienced hobbyist myself, I would attack this replacement display issue from a different perspective. Simply look at the issue from the perspective of someone that is building the device from scratch. Look at the documentation on the official PDF and add any display you like. Simply trace out and note the pinout you already have on your PCB and match it to the documentation then pick a matching display or solder wires yourself to add whatever you want. The makefile (a page that walks you through all of the code options step by step) will help you figure everything out to configure the code to match any display options with a supported controller (see official PDF).
  I have been through almost every bit of documentation for this project on all of the different forums. Of all the displays I've seen, I would probably chose one of the NT7108 based units, I haven't had one in my hands but they look huge. The color stuff seems rather silly if you get a chance to see how slow the MCU is at clearing the screen. I plan to record this in a video at some point while comparing the speed with 8, 16, and 20mhz xtals.

[j-man]

Many thanks for your suggestions and for the links, I'll check them out ASAP.
I'm trying to find the "replacement" display because, as you probably read, I have two damaged testers: one with a zapped chip and one with a broken display. And of course I tried to put together the good board and the good display... it works, but the display is vertically flipped.
I thought it was easier buying a new chip and programming it from scratch, instead of trying to modify existing parameters... but I could be wrong, I'm a perfect newbie in that area.
The main reason, to be honest, is that fixing both testers would be quite gratifying... 
I understand your point and I see the advantages about using "any" display. But it would be a whole new challenge for me... I'm not sure I could manage to get through it.

[madires]

You can flip (horizontally & vertically) or rotate the ouput with most display drivers by enabling that in the Makefile (k-firmware) or in config_328.h (m-firmware).

[j-man]

Yes, thanks, I read it on the manual (page 49-50)
I'll try to get an ISP programmer and play wih it, although I'm still tempted by the other way... trying to get a new display and a new chip.
Thank you guys, this forum is great.

[jakeisprobably]

Of all the random things... I'm on eBay wasting time when all the sudden it "suggested this.

... I guess the ad spys are now trying to manipulate people to share products with others... I was looking at frequency counter auctions when this was suggested.

 Further information: The eBay listing calls this model of a graphic monochrome display a LX-12864B11 LX12864B11 12864B11 (I'm creating search variations here for others to find this easier). This model appears to be the 12 pin connector version if all of the documentation is correct. I have included screenshots of the listing, pictures, and description to keep this information long term.
 I did a search for the part number and it is available from multiple sources. Interestingly it appears to use a ST7567 display driver. One of the links I found while doing a quick search of the LX part number is here.
 This lists a library and further information about the display.

[jakeisprobably]

BTW I finally decided to break a window and adopt a Penguin on my laptop. I also got on KiCad... (talk about none intuitive software... jeez!) That sent me on a search to see if I could find the original KiCad files from KH's main 328 schematic on the Mikrocontroller AVR thread. I'm not sure if the one on the PDF is something Asco B created or if KH made it. I found a few .sch files and .brd files but I didn't see any that were complete with the library file. I also tried scavenging through the tarball, Nick's files, and the yandex clone page looking for them, but I didn't see anything. I tried to search images for every copy of the schematic I could find. I also searched all 10 pages of the official thread by using a "find on page" search for the terms: KiCad, .sch, .brd, and .lib. I did these same searches here on this thread and didn't find anything. The only thing I think I may have missed is if someone posted them as a .zip file and never used the term KiCad in the post (unlikely).
   I figure it's worth asking if anyone has the KiCad file, has recreated it as it is drawn on the official PDF, or knows where I might find it? I'm only looking for that exact layout or very close to it where I can modify it to match easier than completely reconstructing it from scratch.

[j-man]

This model appears to be the 12 pin connector version if all of the documentation is correct.

THANKS A LOT! Your help is unvaluable, I really appreciate it.
Looks exactly like mine. Unfortunately they don't ship to Italy 
But I found it on AliExpress and bought it at once. The keyword is LX-12864B11.
https://it.aliexpress.com/item/1PCS-LOT-LX-12864B11-12864B11-12864-12864-dot-matrix-LCD-display-green-backlight-FREE-SHIPPING/32640521921.html?spm=a2g0y.search0104.3.2.R3JQIb&ws_ab_test=searchweb0_0,searchweb201602_5_10152_10065_10151_10068_5400011_5430020_5410020_10304_10307_10137_10060_10302_10155_10154_10333_10334_10056_5370011_10335_10055_10336_10054_10059_10332_100031_10099_10103_10102_10052_10053_10107_10050_10142_10051_5380020_10326_10084_10083_10080_10082_10081_10177_10110_10111_10112_5390011_10113_10114_10312_10313_10314_10184_10078_10079_10073_5420011,searchweb201603_2,ppcSwitch_5&btsid=fbb0d204-f883-466a-bc3d-1814f94af4b3&algo_expid=e1ee1526-0cad-4b07-9823-34b24825036a-0&algo_pvid=e1ee1526-0cad-4b07-9823-34b24825036a&transAbTest=ae803_3
They sell ICs as well, including ATmega328P. Minimum order 30 pieces... I asked them if it's possible to add just one to my order, but I doubt they will. Let's see.

[jakeisprobably]

Unfortunately they don't ship to Italy.

  It never hurts to ask a seller to ship to your country. Sometimes they don't do it because of customs problems, other times it's because of the complication of creating a shipping profile for every country on eBay. I used to run a medium size eBay business. Setting up each country so that the buyer sees reasonably good shipping costs is a pain. Most people only set up the options for the biggest markets, but will happily sell to anyone if asked
 I shipped top of the line bicycles around the world this way. Many times I shipped to places I never imagined I would sell to because I told people about shipping quote problems on eBay, and gave them package weight, dimensions, and links to shipping quote sites in the description.

Edit: Glad you found what you were looking for

[j-man]

Italian Mail (Poste Italiane) used to be a nightmare for eBay sellers, even more for us customers. They are slightly and slowly improving the quality of their services, but they still have a long way to go. I'm not gonna write about the customers because I could end in jail 
I can't blame a seller that doesn't ship to my country.