skootch13 aaron kuertz cincinnati (31 posts) Registered: 06/30/2020 01:50PM Main British Car: 1973 MGB Rover 4.6 (I'm told) |
Calibrating 1973 MGB tachometer
I have read the article on this site about soldering a potentiometer onto the chip inside the tach.
But the inside of my tach does not look like the one in the article. i believe the article says to solder on posts 4 and 7 (going from memory.) My question is, which of the posts on the chip are 4 and 7? How do you count them? |
skootch13 aaron kuertz cincinnati (31 posts) Registered: 06/30/2020 01:50PM Main British Car: 1973 MGB Rover 4.6 (I'm told) |
Re: Calibrating 1973 MGB tachometer
Leon reached out on mgexperience and told me that number one is next to the indentation on top of the chip.
Also, the correction on the pins in the article on this site is incorrect. It is pins 4 and 7 and not 3 and 8. Here is Leon's page [leonsmgb.com] You can clearly see the indentation on the chip and also his leads on pins 4 and 7. |
MGBV8 Carl Floyd Kingsport, TN (4511 posts) Registered: 10/23/2007 11:32PM Main British Car: 1979 MGB Buick 215 |
Re: Calibrating 1973 MGB tachometer
The confusion with the Figure 1 drawing stems from the capacitor being drawn in the wrong location (pins 3 & 5). The capacitor actually goes across pins 1 & 7.
[www.britishv8.org] |
skootch13 aaron kuertz cincinnati (31 posts) Registered: 06/30/2020 01:50PM Main British Car: 1973 MGB Rover 4.6 (I'm told) |
Re: Calibrating 1973 MGB tachometer
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