Category: reparatie

USBisp V2.0 to USBasp conversion to use TPI (or: USBisp did not connect to usb anymore after fw update – fixed!)

Recently I bought an USBasp, or at least that’s what I thought. I bought a clone that was advertised as “USB ISP USBasp USBisp Programmer for 51 ATMEL AVR download support Win 7 64 (RANDOM COLOR)”, marked on the case as “USB ISP version 2.0” and “MX-USBISP-V5.00” on the PCB. I intend to use this…

18 May 2019
RFID Deel 2 (Of: enkele losse eindjes)

In aanvulling op Opgelost: RC522 RFID lezer leest (sommige) kaarten niet. (Deel 1): Eigenlijk heb ik een groot deel van wat ik van plan was in deel 2 te schrijven, toch al in deel 1 verwerkt. Er zijn echter een paar “losse eindjes”. Van de blauwe kaartlezers uit deel 1 bestaan vele varianten (ook in…

15 May 2019
[fixed] TM1637 LED display “not working”.

Last week I got 2 of these displays from a friend who couldn’t get them to display anything. (He knows I like those challenges.) Below picture proves it now works. What was the case: The data sheet says (e.g. in the schematic at page 8) a 100pF capacitor should be placed on CLK and DIO…

23 March 2018
[gefikst] TM1637 LED display “doet niks”.

Afgelopen week kreeg ik 2 van deze displays van een vriend die ze niet aan de praat kreeg en weet dat ik van dergelijke uitdagingen houd. Op bovenstaande foto het bewijs dat het inmiddels gelukt is het displaytje wél aan de praat te krijgen. Wat was het geval: In de datasheet staat (o.a. in het…

23 March 2018
Fixed: RC522 RFID reader not reading (some) cards (Part 1)

Some of the RC-522 RFID card reader modules that can be bought on ebay / aliexpress have a problem: they do not read all (types of) cards they should be able to read. In this blog post I want to explain how to recognize these faulty readers and how to fix them. (There is a…

8 March 2018
Opgelost: RC522 RFID lezer leest (sommige) kaarten niet. (Deel 1)

Ik heb recent een probleem ontdekt met de RC522 rfid kaartlezer modules die men op ebay / aliexpres en dergelijk kan kopen: ze lezen sommige kaarten niet. In deze blogpost wil ik uitleggen wat het probleem is, en hoe het opgelost kan worden, in de hoop dat mensen die hetzelfde probleem tegenkomen daar wat aan…

7 March 2018
Fine motor skills?

I did not know this was possible. The hollow core motors of a Cheerson CX-10 can actually be opened, and a new wire can be soldered to the brushes when the original one broke of. This started as a challenge, me stating it was impossible to open these motors without damaging them beyond repair and…

6 August 2016
Some short notes on the Lecroy9450 repair project

Because there is no big news yet, some short updates. – Claude Schwarz pointed me to the Yahoo user group “Lecroy Owners group”, they have design files for a HHZ406 replacement. (Made by Dieter Frieauff). So maybe the ext. trigger input can be repaired as well. – A service manual for this ‘scope (And others)…

3 March 2014
LeCroy 9450 oscilloscope repair

This was supposed to be an easy repair, and therefore not worth blogging about. But as it turns out, it might get interesting after all. (The ‘scope is not repaired yet) The “Leidse Makerspace” owns a LeCroy 9450 350Mhz DSO. When they moved to their new location I temporarily got this oscilloscope. Not just for…

26 January 2014