Tekka's Den

For the past couple of weeks, I had trouble with the window wipers on the MGB. Once switched on, they were moving slowly, and after some time they were stopping halfway, stuck on the windscreen... Not very safe when it's raining! And no other possibility to restart them than park, get out of the car and help by hand the wipers to go back to their storage position. So, I have decided to have closer look. The motor and mechanism were encountering mechanical resistance somewhere. The first idea was to extract the motor and the gears attached on top, and open them to check inside. How to remove the motor and gears: The motor is under the dashboard on the right side of the car. It is attached to the car with a metallic strap and 2 bolts. Undo the bolts and disengage the motor from the strap. Once this is done, you should be able to have access to the electrical connector located at the back of the motor. The mechanism (cable) that goes to the wiper arms is connected to the ...

Last Friday, I had my first issue with the MG... Coming home from work, the engine temperature has suddenly started to get really hot, close to the overheating. 😨 I just had time to park the car at home, and seen after opening the bonnet small bubbles and vapour on the hose going from the heater valve to the heater: Of course, there was not enough liquid remaining in the radiator :s Oh c**p! 😨😨 So no choice but to change all the cooling hose, as the other ones were probably in the same state than the perished hose and could split at any time. I have ordered silicone cooling hoses from mgocspares.co.uk ( here ). Similar kits are available at Moss: Those s ilicone hoses are more resistant than the rubber ones to hardening, cracking, ageing and to chemicals. Yes, they are more expensive too! Regarding installation, no real magic trick: drain the old coolant, remove the perished hoses, fit the new silicone ones, fill in with new coolant, start the engine a...

On modern car, usually a buzzer warns you when you leave your lights on while leaving your car. Unfortunately on our oldies, such devices were not always available. That could result in a discharged battery... After having left a couple of time the lights on (but been lucky enough to not have a completely flat battery when returning some hours later), I have decided to install a warning buzzer. Theory: I am using the wiring diagrams from Advance Auto-Wire (document here ). My MGB GT is a 75 UK model. The correct wiring diagram is the one on sheet 31 (page 32 of the pdf file). We want to add a buzzer that detects the parking lights are on when the door is opened. That means we need to connect a buzzer between the parking light feeding wire and the door switch. The parking lights feeding wire is a red & green (RG) starting at the "HEADLIGHT SWITCH", the door switch wires are the purple & white (PW) "COURTESY LAMP & DOOR SWITCHES". ...

Here we are... What are the criteria to choose the "good" controller? - Price of the IC => this one is not a problem, those components are just so... Cheap !! Oo' - Number of pins for this project - Easy to code, as it is a first for me - Size - Availability of the coding software & kit Regarding the size, the idea is to be able to program the controller and install it on the board, or install the controller on the board and upload the code. For this reason, I do not think Arduino is a good idea. Don't get me wrong, I don't say it is not good (I am not an expert) and I should give it a try for another project, just that it does not appear the best solution to have a stand-alone controller for this project without any interface/ intermediary card. Then we have mainly two options: PIC controllers from Microchip or AVR from Atmel. After having spent a long time reading different articles, comparatives, forums, etc etc... Well... Both solutions can...

In this post, we will see how to build the anode driver: - principle, - basic components, - how that works, - how to calculate the proper values The anodes of the Nixie gas tubes need a driver when multiplexed in order to switch the appropriate digit. This driver is built using two transistors (1 NPN and 1 PNP) able to withstand high voltage (the Nixie tubes need 170VDC to switch on). MPSA42 (NPN) and MPSA92 (PNP) are commonly used, as they are available and cheap components. The circuit for the anode driver should be as follow: The resistor R4 is there to limit the current that flows to the Nixie. The tricky part, at least for me was to properly choose the resistors R1 to R4. Let's start with R4, obviously the easiest one. You need to know your Nixie tube characteristics: - voltage to ignite the gas in the tube, - the maximal current the gas tube needs to glow properly. and also how many digits you would multiplex with one anode driver. I have chosen c...

Hello! This is the second post related to the Nixie clock project. Here we will set the architecture of our system. Basically, in order to have a proper clock, from end to start: #1: display device => Nixie tubes #2: cathode driver (in order to select the figure to display) => K555ID1 microchip #3: anode driver (in order to select the tube to switch on) => MPSA42 & MPSA92 #4: oscillator (quartz) #5: controller => PIC 16F1828 #6: interface for setting time on the clock #7: power supply (at least +170V are requested for the tubes and +5V for the different microchips) #3 is requested as we want to have multiplexed Nixie: Multiplexing Nixie means control several tubes with only 1 cathode driver (the straight design would request one driver per tube). This way, one chip will switch on the same cathode on 2 or more tubes. It is necessary then to select which tube to apply voltage on, through the anode driver. Circuit architecture can be summarised as follo...