This new thread has been split off from this old thread:
https://www.electro-tech-online.com/threads/push-to-make-555-4026b-7-seg.147373/
JimB - Moderator
Hello, this is my first post.
I hope this is not the wrong section of the forum, but I think I can connect my question to this post because the topic appears to be similar ...
Sorry, I'm here to ask for help.
I need to modify a circuit schematic because the CD14553 and CD14543 are not more available on the market.
Around there are a lot of schematics that use the CD4026 as 'all in one' counter and decoder,
but I'm not able to replace, with operational certainty, the 14553 and 14543 using the 4026 (or, perhaps, CD4033 ?).
Below you can see the schematic that I need to adapt, leaving in their place, the two display, the 555 and the 4093.
I need to replace only the 4553 and 4543, and, possibly, I do not know if it is necessary,
to recalculate or delete the resistors and the two transistors.
Kindly, could someone help me rewriting the schematics or or suggesting an identical alternative?
I need to realize this PCB, you could suggest even a cheap chinese PCB board that do the same-identical work
and that accept external trigger input as in the schematic.
If you need more infos ...I'm here.
Thank you for reading.
Regards.
https://www.electro-tech-online.com/threads/push-to-make-555-4026b-7-seg.147373/
JimB - Moderator
Hello, this is my first post.
I hope this is not the wrong section of the forum, but I think I can connect my question to this post because the topic appears to be similar ...
Sorry, I'm here to ask for help.
I need to modify a circuit schematic because the CD14553 and CD14543 are not more available on the market.
Around there are a lot of schematics that use the CD4026 as 'all in one' counter and decoder,
but I'm not able to replace, with operational certainty, the 14553 and 14543 using the 4026 (or, perhaps, CD4033 ?).
Below you can see the schematic that I need to adapt, leaving in their place, the two display, the 555 and the 4093.
I need to replace only the 4553 and 4543, and, possibly, I do not know if it is necessary,
to recalculate or delete the resistors and the two transistors.
Kindly, could someone help me rewriting the schematics or or suggesting an identical alternative?
I need to realize this PCB, you could suggest even a cheap chinese PCB board that do the same-identical work
and that accept external trigger input as in the schematic.
If you need more infos ...I'm here.
Thank you for reading.
Regards.
Last edited by a moderator: