Hi,
I've replaced the 2 bax17 in the detection part by by281 but no
success. I've posted the schematic at
http://www.cpc.wmin.ac.uk/~delaitt/PM3240/circuit.jpg
and the following pictures taken with an oscilloscope:
1)
http://www.cpc.wmin.ac.uk/~delaitt/PM3240/P1010339.JPG
collector of TS1308 when intensity is in maximum
voltage goes from 7v to 75v (using 1/10 probe)
2)
http://www.cpc.wmin.ac.uk/~delaitt/PM3240/P1010340.JPG
collector of TS1308 when intensity is in minimum
voltage goes to 50v
3)
http://www.cpc.wmin.ac.uk/~delaitt/PM3240/P1010341.JPG
emitter of TS1306
voltage goes from 8v to 28v when intensity is in maximum
4)
http://www.cpc.wmin.ac.uk/~delaitt/PM3240/P1010343.JPG
emitter of TS1306
voltage is 8V when intensity is in minimum
Cheers,
Thierry.
Jim Yanik wrote:
Thierry Delaitre wrote in
:
Hi,
Is there anyway i could replace the BAX17 with some kind of more
standard diodes for testing purposes ?
Sure,as long as the PIV is equal or better.Small-signal diodes have better
freq. response characteristics,which would affect the risetime of the
unblanking signal to the CRT grid.
You could use the ECG recommended substitute for the BAX17.
--
Jim Yanik
jyanik-at-kua.net