16-04-2017, 09:06 AM
(This post was last modified: 16-04-2017, 09:13 AM by Murphyv310.)
Hi.
The third stage is to check the calibration and set it up. Prior to that it is wise to replace the .22uf cap with a modern high stability type. The recommended way is to use a signal generator on the secondary of the coupling transformer with a square wave. I decided to use a tone generator app on my phone. This has worked a treat and the calibration is spot on at 3000rpm and about 5% error at the ends of the scale, still within Smith's 7% error and well within their staggering 10% error.
I'll be doing a final YouTube video later on.
May I say this movement is the same as in Humbers, Singers, Rovers and Volvos of the 60's so fully relevant.
On a 6 pot engine the frequencies are as follows.
3000rpm....150Hz
6000rpm.....300Hz
1000rpm......50Hz
Etcetera
The third stage is to check the calibration and set it up. Prior to that it is wise to replace the .22uf cap with a modern high stability type. The recommended way is to use a signal generator on the secondary of the coupling transformer with a square wave. I decided to use a tone generator app on my phone. This has worked a treat and the calibration is spot on at 3000rpm and about 5% error at the ends of the scale, still within Smith's 7% error and well within their staggering 10% error.
I'll be doing a final YouTube video later on.
May I say this movement is the same as in Humbers, Singers, Rovers and Volvos of the 60's so fully relevant.
On a 6 pot engine the frequencies are as follows.
3000rpm....150Hz
6000rpm.....300Hz
1000rpm......50Hz
Etcetera
