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Hello all. Its been too cold to get into my workshop for weeks, but now it ain't.
Well, I had finished a board- it didn't work amazingly but it worked. I put that down to my coil.
I then tidied it up and it hasn't worked since.
So I started again. This time I was even more careful with where I put things, types of caps,
earth paths for the signals and the audio,etc.
I used cheap disc ceramics before, this time I used expensive monlithic ceramic caps.
As it was cold I then sat and buzzed through every path - fixing a few errors as I went.
The front panel was a bit of a mess - this time it is very neat and considered.
Switch on. Well, what can I say
It really does function as per the Tesoro handbook, in every way. I have needed to do no tweaking,
no hours with a scope trying to make it better - it just is. Pics to come real soon.
Conclusion:
Yes you can use vero, make your own coil too if you like.
Layout DOES matter - you want as short as poss 'traces' on all the signal 'tracks'.
Separate the audio earth from the rest of it (join at the regulator ground).
Decouple everything. (low cost caps fine, use 100n)
Use good quality caps - monolitihic ceramic
Make a neat job of it!!!
Spend time checking/testing. With no coil or speaker anything more than 20mA is a fault.
I used a 7660 for the -5v rail.
I added a TL555 CMOS timer for low battery alert.
Didn't have the right switches so my RETUNE is a switch all on its own.
If it does not work very well there is a mistake - no point messing with the design unless you
really know what you are doing (no offence there guys).
Prepare a clear scematic to work from and label all the wire colours that come off the board.
Hope this is of interest although most techies will say, 'so what's new ?'
Well, I had finished a board- it didn't work amazingly but it worked. I put that down to my coil.
I then tidied it up and it hasn't worked since.
So I started again. This time I was even more careful with where I put things, types of caps,
earth paths for the signals and the audio,etc.
I used cheap disc ceramics before, this time I used expensive monlithic ceramic caps.
As it was cold I then sat and buzzed through every path - fixing a few errors as I went.
The front panel was a bit of a mess - this time it is very neat and considered.
Switch on. Well, what can I say
It really does function as per the Tesoro handbook, in every way. I have needed to do no tweaking,
no hours with a scope trying to make it better - it just is. Pics to come real soon.
Conclusion:
Yes you can use vero, make your own coil too if you like.
Layout DOES matter - you want as short as poss 'traces' on all the signal 'tracks'.
Separate the audio earth from the rest of it (join at the regulator ground).
Decouple everything. (low cost caps fine, use 100n)
Use good quality caps - monolitihic ceramic
Make a neat job of it!!!
Spend time checking/testing. With no coil or speaker anything more than 20mA is a fault.
I used a 7660 for the -5v rail.
I added a TL555 CMOS timer for low battery alert.
Didn't have the right switches so my RETUNE is a switch all on its own.
If it does not work very well there is a mistake - no point messing with the design unless you
really know what you are doing (no offence there guys).
Prepare a clear scematic to work from and label all the wire colours that come off the board.
Hope this is of interest although most techies will say, 'so what's new ?'