tardishead
Well-known member
- Joined
- Aug 11, 2004
- Messages
- 623
Hi there
I'm restoring a mini compact Farfisa
The schematic for the divider boards is here
http://www.bustedgear.com/repair_Farfisa_minicompact_dividers_4.html
After replacing loads of Ge transistors and finding a hairline crack in one of the cards across all the pcb traces - took hours ouch!!! I got her up and gave it a tune
Sounds awesome
But then after using for about half an hour two of the cards at one point in their divider circuits gave a tone a fifth lower than it should be.
There are not many parts in these divider sections. I checked the transistors and polystyrene caps - ok. Some of the resistors seem to be quite out of tolerance. But can someone explain to me what can be causing this. In the divider sections - the resistors on the collector of the first transistor and the base of the next one - do they set the increment of division? And if these are out of tolerance could that result in this extra interval of division? Also does old resistor tolerance get worse with heat or useage?
:-\
I'm restoring a mini compact Farfisa
The schematic for the divider boards is here
http://www.bustedgear.com/repair_Farfisa_minicompact_dividers_4.html
After replacing loads of Ge transistors and finding a hairline crack in one of the cards across all the pcb traces - took hours ouch!!! I got her up and gave it a tune
Sounds awesome
But then after using for about half an hour two of the cards at one point in their divider circuits gave a tone a fifth lower than it should be.
There are not many parts in these divider sections. I checked the transistors and polystyrene caps - ok. Some of the resistors seem to be quite out of tolerance. But can someone explain to me what can be causing this. In the divider sections - the resistors on the collector of the first transistor and the base of the next one - do they set the increment of division? And if these are out of tolerance could that result in this extra interval of division? Also does old resistor tolerance get worse with heat or useage?
:-\